INVESTIGATION OF ATMOSPHERIC OZONE IMPACTS 

OF 2,3,3,3-TETRAFLUOROPROPENE

Final Report to the 

Honeywell International Inc 

Contract UCR-09010016 

By 

William P. L. Carter 

June 2, 2009 

Center for Environmental Research and Technology 

College of Engineering 

University of California 

Riverside, California 92521 
ii 

ABSTRACT 

An experimental and modeling study was carried out to assess the impacts of 2,3,3,3-

tetrafluoropropene on ground-level ozone formation compared to other chemicals that are emitted into the 

atmosphere. The experiments consisted of incremental reactivity environmental chamber experiments to 

determine the effect of adding the tetrafluoropropene to irradiations of reactive organic gas (ROG) 

surrogate - NOx mixtures representing ambient conditions. The results were modeled using the SAPRC07 mechanism with the reactions of the tetrafluoropropene added. The data were reasonably well 

simulated if it is assumed that nitrate formation from the reactions of peroxy radicals with NO was 

negligible. This mechanism was then used to calculate the atmospheric impact of the tetrafluoropropene 

in the box model scenarios to derive the Maximum Incremental Reactivity (MIR) and other ozone 

reactivity scales. 2,3,3,3-Tetrafluoropropene was calculated to have an ozone impact on a mass basis that 

is the same as that of ethane to within the variability of the model for atmospheric conditions. The 

average ratio of mass-based incremental reactivities relative to ethane was 0.9±0.2 and the MIR ratio was 

1.0±0.1. It is concluded that if ethane is used as the standard to define “negligible” ozone impact for the 

purpose of determining VOC exemptions for ozone precursors, then 2,3,3,3-tetrafluoropropene might 

meet this standard. 2,3,3,3-Tetrafluoropropene was also found to have no significant effect on particle 

formation in the incremental reactivity chamber experiments. 
iii 

ACKNOWLEDGEMENTS AND DISCLAIMERS 

This work was funded by Honeywell International Inc. through contract UCR-09010016. The 

environmental chamber experiments for this project were carried out at the College of Engineering Center 

for Environmental Research and Technology (CE-CERT) primarily by Qi Li, Kurt Bumiller, and Quentin 

Malloy. Mr. Dennis Fitz also provided assistance in administering this project, and Ms. Kathy Cocker 

provided assistance in conducting the experiments and processing the data. 

Although Honeywell International Inc. funded this work, the contents of this report reflect only 

the opinions and conclusions of the author. Mention of trade names and commercial products does not 

constitute endorsement or recommendation for use. 
iv 

TABLE OF CONTENTS 

INTRODUCTION ........................................................................................................................................ 1

EXPERIMENTAL METHODS.................................................................................................................... 2

Chamber Description.............................................................................................................................. 2

Analytical Instrumentation ..................................................................................................................... 4

Sampling methods .................................................................................................................................. 7

Characterization Methods....................................................................................................................... 7

Experimental Procedures........................................................................................................................ 8

Materials................................................................................................................................................. 9

MECHANISM AND MODELING METHODS........................................................................................ 10

Base Mechanism................................................................................................................................... 10

Mechanism for 2,3,3,3-Tefralfuoropropene ......................................................................................... 11

Representation of Chamber Conditions................................................................................................ 12

Atmospheric Reactivity Simulations.................................................................................................... 15

RESULTS AND DISCUSSION ................................................................................................................. 16

Characterization Results....................................................................................................................... 16

Incremental Reactivity and Mechanism Evaluation Results ................................................................ 20

Atmospheric Reactivity Calculation..................................................................................................... 25

CONCLUSIONS......................................................................................................................................... 29

REFERENCES ........................................................................................................................................... 31

APPENDIX A. BASE MECHANISM LISTING....................................................................................... 35
v 

LIST OF TABLES 

Table 1. List of analytical and characterization instrumentation for the UCR EPA chamber................. 5

Table 2. List of model species added to the base mechanism to represent the atmospheric 

reactions of 2,3,3,3-tetrafluoropropene and its oxidation products........................................ 13

Table 3. List of reactions and rate constants used to represent the atmospheric reactions of 

2,3,3,3-tetrafluoropropene and its oxidation products ........................................................... 14

Table 4. Summary of experiments carried out for this project.............................................................. 17

Table 5. Summary of initial concentrations and selected gas-phase results of the incremental 

reactivity experiments. ........................................................................................................... 21

Table 6. Summary of conditions of scenarios used for reactivity assessment....................................... 26

Table 7. Calculated atmospheric incremental reactivities for 2,3,3,3-tetrafluoropropene and 

ethane. .................................................................................................................................... 28

Table A-1. List of model species used in the base SAPRC-07 mechanism, including the VOC 

species used in the chamber and atmospheric reactivity simulations.. .................................. 35

Table A-2. Reactions and rate constants in the SAPRC-07 mechanism used in this work. See 

Carter (2009a) for documentation.......................................................................................... 39

Table A-3. Summary of photolysis rates used in chamber and ambient simulations............................... 55
vi 

LIST OF FIGURES 

Figure 1. Schematic of the UCR EPA environmental chamber reactors and enclosure........................... 3

Figure 2. Spectrum of the light sources used in the UCR EPA chamber, with intensities 

normalized to give the same NO2 photolysis rates................................................................... 3

Figure 3. Plots of best fit HONO offgasing parameters against UCR EPA run number. ....................... 19

Figure 4a. Experimental and calculated results of the incremental reactivity experiments with 

added 2,3,3,3-tetrafluoropropene. .......................................................................................... 22

Figure 5. Plots of reactivities of 2,3,3,3-tetrafluoropropene relative to ethane against relative 

NOx levels for all the scenarios used for reactivity assessment. ............................................ 27
1 

INTRODUCTION 

Ozone in photochemical smog is formed from the gas-phase reactions of volatile organic 

compounds (VOCs) and oxides of nitrogen (NOx) in sunlight, and control of both VOCs and NOx is 

required to attain air quality standards for ozone. Many different types of VOCs are emitted into the 

atmosphere, each reacting at different rates and having different mechanisms for their reactions. Because 

of this, they can differ significantly in their effects on ozone formation, or their “reactivity”. In 

recognition of this, the U.S. EPA has exempted volatile organic certain compounds with ozone impacts 

expected to be less than ethane from regulations as VOC ozone precursors (Dimitriades, 1999; RRWG, 

1999a, EPA, 2005), and the California Air Resources Board (CARB) has adopted regulations with 

reactivity-based adjustments for several types of VOC sources (CARB 1993, 2000) and is investigating 

their use for other sources (CARB, 2008). 

Fluorinated propenes such as 2,3,3,3-tetrafluoropropene (CF3CF=CH2) are compounds of interest 

to Honeywell Specialty Materials Company whose use and manufacture may result in their being emitted 

into the atmosphere. This will result in these compounds being subject to VOC regulations aimed at 

reducing ozone formation, which may adversely impact their production costs and marketability. If these 

compounds can be shown to have ozone impacts less than or equal to ethane on a mass basis, a case might 

be made to the U.S. EPA to exempt them from regulations as VOC ozone precursors (EPA, 2005). 

Because of this, Honeywell contracted us to develop estimates of ozone impacts of these compounds in 

various ozone reactivity scales, and compare them with the ozone impacts for ethane (Carter, 2009a). 

The results of our assessment indicated that 2,3,3,3-tetrafluoropropene has about the same ozone 

impact as ethane on a mass basis (Carter, 2008). However, the ability of mechanisms to predict ozone 

impacts had not been experimentally verified for this compound, and an experimental study is required to 

support the use of these reactivity values in a petition to the EPA to exempt this compound from 

regulations on the basis of relatively low reactivity for ozone formation. 

In view of this, Honeywell Corporation funded the College of Engineering, Center for 

Environmental Research and Technology (CE-CERT) at the University of California at Riverside (UCR) 

to carry out a project to reduce uncertainties in estimates of the atmospheric ozone impacts of 2,3,3,3-

tetrafluoropropene. This included conducting environmental chamber experiments suitable for testing 

mechanisms for the gas-phase atmospheric reactions of this compound that affect ozone formation, using 

the results to evaluate the mechanism previously derived for this compound, revising or adjusting the 

mechanism to simulate the data, and recalculating its atmospheric impacts if the mechanism is revised. 

The approach used is similar to that used many other VOCs that have been studied previously (Carter, 

2009a, and references therein), including the fluorinated propene trans 1,3,3,3-tetrafluoropropene that was 

studied previously for Honeywell (Carter, 2009b). The methods, results, and conclusions of this project 

are documented in this report. 
2 

EXPERIMENTAL METHODS 

Chamber Description 

All of the environmental chamber experiments for this project were carried out using the UCR 

EPA environmental chamber at CE-CERT. This is the same as the chamber used in our recently 

completed study of trans 1,3,3,3-tetrafluoropropene (Carter, 2009b). This chamber was constructed under 

EPA funding to address the needs for an improved environmental chamber database for mechanism 

evaluation (Carter et al, 1999, Carter, 2002). The objectives, design, construction, and results of the initial 

evaluation of this chamber facility are described in more detail elsewhere (Carter et al, 1999, Carter, 

2002; Carter, 2004, Carter et al, 2005a). A brief description of the chamber is also given below. 

The UCR EPA chamber consists of two ~85,000-liter Teflon® reactors located inside a 16,000 

cubic ft temperature-controlled “clean room” that is continuously flushed with purified air. The clean 

room design is employed in order to minimize background contaminants into the reactor due to 

permeation or leaks. Two alternative light sources can be used. The first consists of a 200 KW argon arc 

lamp with specially designed UV filters that give a UV and visible spectrum similar to sunlight. Banks of 

blacklights are also present to serve as an alternative lower cost light source when blacklight irradiation is 

sufficient. Blacklights have a good representation of sunlight in the UV portion of the spectrum that 

affects most photolysis reactions of interest, and their use is sufficient for test compounds whose 

mechanisms involve do not involve photoreactive compounds, or only photoreactive compounds with 

known action spectra (Carter et al, 1995b). Since this is the case for the fluoropropenes studied here and 

by Carter (2009b), they were used for all experiments for this project. The interior of the enclosure is 

covered with reflective aluminum panels in order to maximize the available light intensity and to attain 

sufficient light uniformity, which is estimated to be ±10% or better in the portion of the enclosure where 

the reactors are located (Carter, 2002). A diagram of the enclosure and reactors is shown in Figure 1, and 

spectra of the light sources are shown in Figure 2. 

The dual reactors are constructed of flexible 2 mil Teflon® film, which is the same material used 

in the other UCR Teflon chambers used for mechanism evaluation (e.g., Carter et al, 1995a; Carter, 

2000a, and references therein). A semi-flexible framework design was developed to minimize leakage 

and simplify the management of large volume reactors. The Teflon film is heat-sealed into separate sheets 

for the top, bottom, and sides (the latter sealed into a cylindrical shape) that are held together and in place 

using bottom frames attached to the floor and moveable top frames. The moveable top frame is held to the 

ceiling by cables that are controlled by motors that raise the top to allow the reactors to expand when 

filled or lower the top to allow the volume to contract when the reactors are being emptied or flushed. 

These motors in turn are controlled by pressure sensors that raise or lower the reactors as needed to 

maintain slight positive pressure. During experiments the top frames are slowly lowered to maintain 

continuous positive pressure as the reactor volumes decrease due to sampling or leaks. The experiment is 

terminated once the volume of one of the reactor reaches about 1/3 the maximum value, where the time 

this took varied depending on the amount of leaks in the reactor, but was greater than the duration of most 

of the experiments discussed in this report. Since at least some leaks are unavoidable in large Teflon film 

reactors, the constant positive pressure is important to minimize the introduction of enclosure air into the 

reactor that may otherwise result. 

As indicated in Figure 1, the floor of the reactors has openings for a high volume mixing system 

for mixing reactants within a reactor and also for exchanging reactants between the reactors to achieve 
3 

20 ft. 20 ft.

20 

 ft. 

This volume kept clear 

to maintain light 

uniformity 

Temperature controlled room flushed 

with purified air and with reflective 

material on all inner surfaces 

Dual Teflon 

Reactors 

Two air Handlers 

are located in the 

corners on each 

side of the light 

(not shown). 

Gas sample lines to 

laboratory below Access 

Door 

200 KW 

Arc Light 

2 Banks of 

Blacklights 

SEMS (PM) 

Instrument 

Floor Frame 

Movable top 

frame allows 

reactors to 

collapse 

under 

pressure 

control 

Mixing System

Under floor 

of reactors 

Figure 1. Schematic of the UCR EPA environmental chamber reactors and enclosure. 

0.0

0.2

0.4

0.6

0.8

0.300 0.350 0.400 0.450 0.500 0.550 0.600

Wavelength (microns)

Arc Light

Blacklights

Solar Z=0

0.00

0.02

0.04

0.06

0.08

0.10

0.12

Relative Intensity (Normalized to give

0.290 0.300 0.310 0.320

same NO2 photolysis rate)

Figure 2. Spectrum of the light sources used in the UCR EPA chamber, with intensities normalized 

to give the same NO2 photolysis rates. A representative solar spectrum is also shown. 
4 

equal concentrations in each. This utilizes four 10” Teflon pipes with Teflon-coated blowers and flanges 

to either blow air from one side of a reactor to the other, or to move air between each of the two reactors. 

Teflon-coated air-driven metal valves are used to close off the openings to the mixing system when not in 

use, and during the irradiation experiments. 

An AADCO air purification system that provides dry purified air at flow rates up to 1500 liters 

min-1 is used to supply the air to flush the enclosure and to flush and fill the reactors between 

experiments. The air is further purified by passing it through cartridges filled with Purafil® and heated 

Carulite 300® which is a Hopcalite® type catalyst and also through a filter to remove particulate matter. 

The measured NOx, CO, and non-methane organic concentrations in the purified air were found to be less 

than the detection limits of the instrumentation employed (see Analytical Equipment, below). 

The chamber enclosure is located on the second floor of a two-floor laboratory building that was 

designed and constructed specifically to house this facility (Carter et al, 2002). Most of the analytical 

instrumentation is located on the ground floor beneath the chamber, with sampling lines leading down as 

indicated in Figure 1. 

Analytical Instrumentation 

Table 1 gives a listing of the analytical and characterization instrumentation whose data were 

utilized for this project. Other instrumentation was available and used for some of these experiments, as 

discussed by Carter 2002a and Carter et al, 2005a, but the data obtained were not characterized for 

modeling and thus not used in the mechanism evaluations for this project. The table includes a brief 

description of the equipment, species monitored, and their approximate sensitivities, where applicable. 

These are discussed further in the following sections. 

Ozone, CO, NO, and NOy were monitored using commercially available instruments as indicated 

in Table 1. The instruments were spanned for NO, NO2, and CO and zeroed prior to all experiments using 

the gas calibration system indicated in Table 1, and a prepared calibration gas cylinder with known 

amounts of NO and CO. O3 and NO2 spans were conducted by gas phase titration using the calibrator 

during this period. Span and zero corrections were made to the NO, NO2, and CO data as appropriate 

based on the results of these span measurements, and the O3 spans indicated that the UV absorption 

instrument was performing within its specifications. 

Organic reactants were measured by gas chromatography with FID detection as described 

elsewhere (Carter et al, 1995a); see also Table 1. The surrogate gaseous compounds ethylene, propylene, 

n-butane and trans-2-butene were monitored by using 30 m megabore GS-Alumina column and the loop 

sampling system. The second signal of the same GC outfitted with FID, loop sampling system and 30 m 

megabore DB-5 column was used to analyze surrogate liquid components toluene, n-octane and mxylene. The sampling methods employed for injecting the sample with the test compounds on the GC 

column depended on the volatility or “stickiness” of the compounds. For analyses of more volatile specie 

such as 2,3,3,3-tetrafluoropropene the same loop method was suitable. 

Both the GC instruments were controlled and their data were analyzed using Agilent 

ChemStation software installed on a dedicated PC. The GC's were spanned using the prepared calibration 

cylinder with known amounts of ethylene, propane, propylene, n-butane, n-hexane, toluene, n-octane and 

m-xylene in ultrapure nitrogen. Analyses of the span mixture were conducted approximately every day an 

experiment was run, and the results were tracked for consistency. 
5 

Table 1. List of analytical and characterization instrumentation for the UCR EPA chamber. 

Type Model or Description Species Sensitivity Comments 

 

Ozone 

Analyzer 

Dasibi Model 1003-AH. UV 

absorption analysis. 

O3 2 ppb Standard monitoring instrument. 

NO - NOy NO 1 ppb 

Analyzer 

Teco Model 42 C with external 

converter. Chemiluminescent 

analysis for NO, NOy by 

catalytic conversion. 

NOy 1 ppb 

Useful for NO and initial NO2

monitoring. Converter close-coupled to 

the reactors so the “NOy” channel should 

include HNO3 as well as NO2, PANs, 

organic nitrates, and other species 

converted to NO by the catalyst. 

CO Analyzer Thermo Environmental 

Instruments Inc. Model 48 C 

CO 50 ppb Standard monitoring instrument 

GC-FID 

Instruments 

Dual Agilent 6890 Series II 

GC with dual columns, loop 

injectors and FID detectors. 

Controlled by computer 

interfaced to network. 

VOCs ~10 ppbC 30 m x 0.53 mm GS-Alumina column 

used for the analysis of light 

hydrocarbons such as ethylene, 

propylene, n-butane and trans-2-butene 

and 30 m x 0.53 mm DB-5 column used 

for the analysis of C5+ alkanes and 

aromatics, such as toluene and m-xylene. 

Loop injection is suitable for low to 

medium volatility VOCs that are not too 

“sticky” to pass through valves. Two 30 

m x 0.32 mm DB-5 column measure C5+

alkanes and aromatics, such as toluene 

and m-xylene. 

Gas 

Calibrator 

Model 146C Thermo 

Environmental Dynamic Gas 

Calibrator 

N/A N/A Used for calibration of NOx and other 

analyzers. Instrument acquired early in 

project and under continuous use. 

Data 

Acquisition 

Sytem 

Windows PC with custom 

LabView software, 16 analog 

input, 40 I/O, 16 thermocouple, and 8 RS-232 channels. 

N/A N/A Used to collect data from most 

monitoring instruments and control 

sampling solenoids. In-house LabView 

software was developed using software 

developed by Sonoma Technology for 

ARB for the Central California Air 

Quality Study as the starting point. 

Temperature 

sensors 

Various thermocouples, 

radiation shielded 

thermocouple housing 

Tempera

-ture 

~0.1 o

C Primary measurement is thermocouples 

inside reactor. However, comparison with 

temperature measurements in the sample 

line suggest that irradiative heating may 

bias these data high by ~2.5o

C (Carter, 

2004). 

Humidity 

Monitor 

General Eastern HYGRO-M1 

Dew Point Monitor 

Humidity Dew point 

range: -40 - 

50o

C 

Instrument performs as expected, but dew 

point below the performance range for 

most of the experiments discussed in this 

report, except for those with added 

humidity. 
Table 1 (continued) 

6 

Type Model or Description Species Sensitivity Comments 

 

Spectroradiometer LiCor LI-1800 

Spectroradiometer 

300-850 

nm Light 

Spectrum 

Adequate Resolution relatively low but adequate 

for this project. Used to obtain relative 

spectrum. Also gives an absolute 

intensity measurement on surface useful 

for assessing relative trends. 

QSL 

Spherical 

Irradiance 

Sensor 

Biospherical QSL-2100 PAR 

Irradiance Sensor. Responds to 

400-700 nm light. 

Spherical 

Broadband 

Light 

Intensity

Adequate Provides a measure of absolute intensity 

and light uniformity that is more directly 

related to photolysis rates than light 

intensity on surface. Gives more precise 

measurement of light intensity trends 

than NO2 actinometry, but is relatively 

sensitive to small changes in position. 

Scanning 

Mobility 

Particle Sizer 

(SMPS) 

TSI 3080L column, TSI 3077 

85Kr neutralizer, and TSI 3771 

CPC. Instrument design, 

control, and operation Similar 

to that described in Cocker et 

al. (2001) 

Aerosol 

number 

and size 

distributions 

Adequate Provides information on size distribution 

of aerosols in the 28-735 nm size range, 

which accounts for most of the aerosol 

mass formed in our experiments. Data 

can be used to assess effects of VOCs on 

secondary PM formation. 

The surrogate components analyzed by the above system were calibrated by repeated analysis of 

a standard mixture containing these compounds, and verified by injecting and sampling known amounts 

of the compound in calibration chamber of known volume. The amounts of gaseous compounds injected 

were determined by vacuum methods, using an MKS Baratron precision pressure gauge, and bulbs of 

known volume, determined by weighing when filled with water. The amounts of liquid compounds 

injected were determined by measuring amounts injected using microliter syringes. The volumes of the 

calibration chambers were determined by injecting and analyzing compounds whose analyses have been 

calibrated previously. 

The GC analysis of 2,3,3,3-tetrafluoropropene was calibrated by injecting a quantitative amount 

of the compound in the chamber reactors. The chamber reactors have a known volume and therefore 

contain a known concentration of the injected compound. The calibration factor was then determined as a 

result of the GC analyses conducted prior to the start of the irradiations. 

 As indicated in Table 1, aerosol number and size distributions were also measured in conjunction 

with our experiments. The instrumentation employed is similar to that described by Cocker et al. (2001), 

and is the same as employed in our previous studies of coatings VOCs (Carter et al, 2005b). Particle size 

distributions are obtained using a scanning mobility particle sizer (SMPS) equipped with a 3077 85Kr 

charger, a 3081L cylindrical long column, and a 3771 condensation particle counter (CPC). Flow rates of 

2.5 LPM and 0.25 LPM for sheath and aerosol flow, respectively, are maintained using Labview 6.0-

assisted PID control of MKS proportional solenoid control valves. Both the sheath and aerosol flow are 

obtained from the reactor enclosure. The data inversion algorithm described by Collins et al (2002) 

converts CPC counts versus time to particle size distribution. 

Most of the instruments other than the GCs and aerosol instrument were interfaced to a PC-based 

computer data acquisition system under the control of a LabView program written for this purpose. These 

data, and the GC data from the Agilent ChemStation computer, were collected over the CE-CERT 
7 

computer network and merged into Excel files that are used for applying span, zero, and other corrections, 

and preparation of the data for modeling. 

Sampling methods 

Samples for analysis by the continuous monitoring instruments were withdrawn alternately from 

the two reactors and zero air, under the control of solenoid valves that were in turn controlled by the data 

acquisition system discussed above. For most experiments the sampling cycle was 5 minutes for each 

reactor, the zero air, or (for control purposes) the chamber enclosure. The program controlling the 

sampling sent data to the data acquisition program to indicate which state was being sampled, so the data 

could be appropriately apportioned when being processed. Data taken less than 3-4 minutes after the 

sample switched were not used for subsequent data processing. The sampling system employed is 

described in more detail by Carter (2002). 

Samples for GC analysis of surrogate compounds were taken at approximately every 20-minute 

directly from each of the reactors through the separate sample lines attached to the bottom of the reactors. 

The GC sample loops were flushed for a desired time with the air from the reactor being sampled. 

Characterization Methods 

Use of chamber data for mechanism evaluation requires that the conditions of the experiments be 

adequately characterized. This includes measurements of temperature, humidity, light and wall effects 

characterization. Wall effects characterization is discussed in detail by Carter (2004) and updated by 

Carter and Malkina (2005) and Carter (2007) and most of that discussion is applicable to the experiments 

for this project. The instrumentation used for the other characterization measurements is summarized in 

Table 1, above, and these measurements are discussed further below. 

Temperature was monitored during chamber experiments using calibrated thermocouples 

attached to thermocouple boards on our computer data acquisition system. The temperature in each of the 

reactors was continuously measured using relatively fine gauge thermocouples that were located ~1 foot 

above the floor of the reactors. These thermocouples were not shielded from the light, though it was 

hoped that irradiative heating would be minimized because of their small size. Experiments where the 

thermocouple for one of the reactors was relocated to inside the sample line indicated that radiative 

heating is probably non-negligible, and that a correction needs to be made for this by subtracting ~2.5o

C 

from the readings of the thermocouples in the reactors. This is discussed by Carter (2004). 

Light Spectrum and Intensity. The spectrum of the light source in the 300-850 nm region was 

measured using a LiCor LI-1800 spectroradiometer, which is periodically calibrated at the factory. 

Spectroradiometer readings were taken periodically, though the relative spectra were found to have very 

little variation during the course of these experiments. The absolute light intensity is measured by 

carrying out NO2 actinometry experiments periodically using the quartz tube method of Zafonte et al 

(1977) modified as discussed by Carter et al (1995a). In most cases the quartz tube was located in front of 

the reactors. Since this location is closer to the light than the centers of the reactors, the measurement at 

this location is expected to be biased high, so the primary utility of these data are to assess potential 

variation of intensity over time. However, several special actinometry experiments were conducted prior 

to the experiments carried out for this project where the quartz tube was located inside the reactors, to 

provide a direct measurement of the NO2 photolysis rates inside the reactors. The photolysis rates used 

when modeling these experiments were the same as used by Carter (2009b) when modeling the recently 

completed experiments for trans 1,3,3,3-tetrafluoropropene. 
8 

Experimental Procedures 

The reaction bags were collapsed to the minimum volume by lowering the top frames, then 

cleaned by emptying and refilling them at least six times after each experiment, and then filled with dry 

purified air on the nights before experiments. Span measurements were generally made on the continuous 

instruments prior to injecting the reactants for the experiments. The reactants were then injected through 

Teflon injection lines (that are separate from the sampling lines) leading from the laboratory below to the 

reactors. The common reactants were injected in both reactors simultaneously, and were mixed by using 

the reactor-to-reactor exchange blowers and pipes for 10 minutes. The valves to the exchange system 

were then closed and the other reactants were injected to their respective sides and mixed using the inreactor mixing blowers and pipes for 1 minute. The contents of the chamber were then monitored for at 

least 30 minutes prior to irradiation, and samples were taken from each reactor for GC analysis. 

 Once the initial reactants are injected, stabilized, and sampled, the light or lights employed 

(argon arc or blacklights) are turned on to begin the irradiation. During the irradiation the contents of the 

reactors are kept at a constant positive pressure by lowering the top frames as needed, under positive 

pressure control. The reactor volumes therefore decrease during the course of the experiments, in part due 

to sample withdrawal and in part due to small leaks in the reactor. A typical irradiation experiment ended 

after about 6 hours, by which time the reactors are typically down to about half their fully filled volume. 

Larger leaks are manifested by more rapid decline of reactor volumes, and the run is aborted early if the 

volume declines to about 1/3 the maximum. This was the case for a few of the experiments discussed in 

this report. After the irradiation the reactors were emptied and filled six times as indicated above. 

The procedures for injecting the various types of reactants were as follows. The NO, and NO2

were prepared for injection using a vacuum rack. Known pressures of NO, measured with MKS Baratron 

capacitance manometers, were expanded into Pyrex bulbs with known volumes, which were then filled 

with nitrogen (for NO) or purified air (for NO2). In order to maintain constant NO/NO2 ratios the same 

two bulbs of specified volume were utilized in most of experiments. The contents of the bulbs were then 

flushed into the reactor(s) with nitrogen. Some of the gaseous reactants such as propylene (other than for 

surrogate experiments) and 2,3,3,3-tetrafluoropropene were prepared for injection using a high vacuum 

rack as well. For experiments with added CO, the CO was purified by passing it through an in-line 

activated charcoal trap and flushing it into the reactor at a known rate for the amount of time required to 

obtain the desired concentration. Measured volumes of volatile liquid reactants were injected, using a 

micro syringe, into a 2 ft long Pyrex injection tube surrounded with heat tape and equipped with one port 

for the injection of the liquid and other ports to attach bulbs with gas reactants. For injections into both 

reactors (e.g, the NOx and base ROG surrogate components in incremental reactivity experiments), one 

end of the injection tube was attached to the “Y”-shape glass tube (equipped with stopcocks) that was 

connected to reactors and the other end of injection tube was connected to a nitrogen source. The 

injections into a single reactor (e.g., for 2,3,3,3-tetrafluoropropene in the reactivity experiments) was 

similar except the “Y” tube was not used. 

The procedures for injection of the hydrocarbon surrogate components were as follows. A 

cylinder containing n-butane, trans-2-butene, propylene and ethylene in nitrogen, was used for injecting 

the gaseous components of the surrogate. The cylinder was attached to the injection system and a gas 

stream was introduced into reactors at controlled flow for certain time to obtain desired concentrations. A 

prepared liquid mixture with the appropriate ratios of toluene, n-octane and m-xylene was utilized for 

injection of these surrogate components, using the procedures as discussed above for pure liquid 

reactants. All the gas and liquid reactants intended to be the same in both reactors were injected at the 

same time. The injection consisted of opening the stopcocks and flushing the contents of the bulbs and the 

liquid reactants with nitrogen, with the liquid reactants being heated slightly using heat that surrounded 

the injection tube. The flushing continued for approximately 10 minutes. 
9 

Problems were encountered during the injections of the surrogate components for some of the 

experiments for this project, resulting from concentrations different from those intended in the 

experimental design. This is indicated where applicable in the table in the Results section giving the 

chronological summary of the experiments. Although the initial concentrations were different from those 

intended, the results were still useful for mechanism testing, and modeling these experiments are included 

among the results. The primary consequence of these injection problems was a larger number of 

experiments being conducted with this compound than was initially intended. 

The 2,3,3,3-tetrafluoropropene used in these experiments was provided as a gas in a lecture 

bottle, and was injected into the chamber using vacuum injection methods similar to that discussed above 

for NO and other gaseous reactants. 

Materials 

The sources of the NO, CO and the various base case surrogate compounds came from various 

commercial vendors as employed in previous projects at our laboratory. The 2,3,3,3-tetrafluoropropene, 

with a stated purity of ≥ 99.9%, was provided by Honeywell. No significant impurities were detected in 

any of the GC analyses of these samples. 
10 

MECHANISM AND MODELING METHODS 

Base Mechanism 

The starting point for the chemical mechanism evaluated in this work is the SAPRC-07 

mechanism as documented by Carter (2009a). This is a complete update of the SAPRC-99 mechanism of 

Carter (2000a), but it is very similar to it in its major features. The reactions and rate constants in this 

mechanism are given in tables in Appendix A to this report, and complete documentation of this 

mechanism is given by Carter (2009a). Files and software implementing this chemical mechanism are 

available at the SAPRC mechanism web site1

, with the chemical mechanism simulation computer 

programs available there being essentially the same as those employed in this work. 

As discussed previously (Carter, 2000a,b, 2009a), the current SAPRC mechanisms consists of a 

“base mechanism” that represents the reactions of the inorganic species and common organic products 

and lumped organic radical model species and “operators”, and separate mechanisms for the initial 

reactions of the many types other organic compounds that are not in the base mechanism. The 

compounds, or groups of compounds, that are not included in the base mechanism but for which 

mechanism assignments have been made, are referred to as detailed model species. The latter include all 

the base ROG surrogate constituents and compounds whose reactivities are being assessed (2,3,3,3-

tetrafluoropropene in this case). These compounds can either be represented explicitly, with separate 

model species with individual reactions or sets of reactions for each, or using lumped model species 

similar to those employed in the “fixed parameter” version of SAPRC (Carter, 2000b, 2009a). The latter 

approach is used when modeling complex mixtures in ambient simulations or simulations of experiments 

with complex mixtures, but the other approach, representing each compound explicitly, is more 

appropriate when evaluating mechanisms for individual compounds or simple mixtures. This is because 

the purpose of mechanism evaluations against chamber data is to assess the performance of the 

mechanism itself, not to assess the performance lumping approaches. The latter is most appropriately 

assessed by comparing simulations of explicit and condensed versions of the same mechanism in ambient 

simulations. 

In this work, all of the organic constituents in the environmental chamber experiments were 

represented explicitly using separate model species for each compound, while complex mixture of emitted 

species in the atmospheric reactivity simulations were represented using the appropriate lumped model 

species for the fixed parameter mechanism, as indicted in Table A-1 in Appendix A. The reactions and 

rate constants in the base mechanism are given in Table A-2, and the photolysis rates used are given in 

Table A-3. These photolysis rates were calculated from applicable actinic flux or light source 

characterization data and absorption cross-sections and quantum yields given by Carter (2009a). 

The version of the SAPRC-07 mechanism used in this work incorporated several corrections 

relative to the version used in our study of trans 1,3,3,3-tetrafluoropropene (Carter, 2009b), as discussed 

in Appendix E of Carter (2009a). The relevant corrections primarily concern hydroperoxide reactions that 

are not important in affecting ozone formation and have no significant affect calculations of ozone 

impacts of these tetrafluoropropenes. 

 

1

 Reports and files concerning the latest version of the SAPRC chemical mechanisms and their associated 

reactivity scales are available at http://www.cert.ucr.edu/ ~carter/SAPRC. 
11 

Mechanism for 2,3,3,3-Tefralfuoropropene 

Alkenes can react in the atmosphere with OH radicals, O3 or NO3 radicals, and in general all three 

need to be taken into account when developing mechanisms for their O3 formation potential. The rate 

constants for the reactions of 2,3,3,3-tetrafluoropropene with OH radicals and O3 have been measured to 

be 1.05 x 10-12 and 2.77 x 10-21 cm3

 molec-1 s-1, respectively (Nielsen et al, 2007). The rate constant for the 

reaction with O3 is too low for this reaction to be an important sink compared to reaction with OH 

radicals, so it can be ignored. The rate constant for reaction with NO3 radicals have not been measured, 

but can be estimated by correlation between measured OH and NO3 radical rate constants for other 

alkenes (e.g., see Atkinson, 1991; Calvert et al, 2003; Carter, 2000). Based on this correlation, the rate 

constant for the reactions of 2,3,3,3-tetrafluoropropene is estimated to be less than 10-22 cm3

 molec-1 s-1, 

making it negligible under atmospheric conditions. Nielsen et al (2007) obtained a relatively high rate 

constant of 7.03 x 10-11 cm3

 molec-1 s-1 for the reactions of this compound with chlorine atoms, but 

chlorine atom reactions are not expected to be important sinks for VOCs under most atmospheric 

conditions, including those used for ozone reactivity assessment in this work. 

Therefore, the only loss process for 2,3,3,3-tetrafluoropropene that needs to be considered in 

estimating its ozone impact is reaction with OH radicals. Hurley et al (2007) studied this reaction and 

found that the major product was CH3C(O)F, with a 91±6% yield. This is consistent with the following 

mechanism for the OH reaction, and is also consistent with mechanisms for OH reactions with most other 

alkenes (Calvert et al, 2003; Carter, 2000, 2008): 

 OH + CF3CF=CH2 → CF3CF(OH)CH2· 

 OH + CF3CF=CH2 → CF3CF(·)CH2OH 

 CF3CF(OH)CH2· + O2 → CF3CF(OH)CH2OO· 

 CF3CF(·)CH2OH + O2 → CF3CF(OO·)CH2OH 

 CF3CF(OH)CH2OO· + NO → NO2 + CF3CF(OH)CH2O· 

 CF3CF(OO·)CH2OH + NO → NO2 + CF3CF(O·)CH2OH 

 CF3CF(OH)CH2O· → CF3C(OH)(·)F + HCHO 

 CF3CF(O·)CH2OH → CF3C(O)F + ·CH2OH 

 CF3C(OH)(·)F + O2 → HO2 + CF3C(O)F 

 ·CH2OH + O2 → HO2 + HCHO 

or overall: 

 OH + CF3CF=CH2 → CF3C(O)F + HCHO + HO2 - NO + NO2

Note that the experimental system of Hurley et al (2007) was such that the predicted formation of 

formaldehyde as the co-product could not be detected because formaldehyde is formed in the methyl 

nitrite system they used to generate the OH radicals. 

An additional reaction that needs to be considered is the formation of organic nitrates as a minor 

route in the reaction of peroxy radicals with NO, e.g., 

 CF3CF(OH)CH2OO· + NO → CF3CF(OH)CH2ONO2

This reaction is assumed to occur ~1.5% of the time in the propene system (Carter, 2009a), but noncarbon substituents are expected to reduce the importance of this reaction further (Carter, 2000, and 

references therein), so this reaction was neglected in the initial estimates of Carter (2008). However, to fit 

the chamber data for trans 1,3,3,3-tetrafluoropropene, Carter (2009b) had to assume that nitrate formation 

in the reaction of the CF3CH(OH)CHFOO· and CF3CH(OO·)CHFOH radicals formed in that system 

occurred ~5% of the time. Since the radicals formed in this case is very similar and isomers of these 

formed from trans 1,3,3,3-tetrafluoropropene, we initially assume that overall nitrate formation also 

occurs 5% of the time in the 2,3,3,3-tetrafluoropropene system. However, as discussed below the best fit 
12 

to the chamber data were obtained assuming that overall nitrate formation is negligible, so this was used 

in the final model developed for this project. 

The secondary reactions of the products formed also need to be considered when estimating the 

ozone impacts of a VOC. The reactions of formaldehyde are already incorporated in the base atmospheric 

chemical mechanism used in this work, which was discussed above (Carter, 2009a). CF3C(O)F is not 

expected to react at a significant rate and therefore its subsequent reactions are ignored. It has no known 

means for it to react with OH radicals or other atmospheric species, and it has no light absorption in the 

wavelength region important in the lower atmosphere (IUPAC, 2004). 

The above discussion focuses on the reactions of the tetrafluoropropene and its oxidation 

products in the presence of NOx, which are the major reactions of significance in affecting their ozone 

impacts. However, to estimate the ultimate environmental fate of this compound and its fluorinecontaining products, one needs to also consider the reactions in the absence of NOx, and the reactions of 

products formed under such conditions. The most important reactions in the absence of NOx are reactions 

of the peroxy radicals with HO2. For the initially formed peroxy radicals, these include the following: 

 CF3CF(OH)CH2OO· + HO2 → O2 + CF3CF(OH)CH2OOH 

 CF3CF(OO·)CH2OH + HO2 → O2 + CF3CF(OOH)CH2OH 

 CF3CF(OH)CH2OOH + OH → H2O + CF3CF(OH)CH2OO· 

 CF3CF(OO·)CH2OH + OH → H2O + CF3CF(OO·)CH2OH 

 CF3CF(OH)CH2OOH + hν → CF3CF(OH)CH2O· + OH 

 CF3CF(OO·)CH2OH + hν → CF3CF(O·)CH2OH + OH 

The subsequent reactions of the alkoxy radicals formed in the photolyses are as shown above, and the rate 

constants and photolysis rates are estimated based on those for methyl hydroperoxide. The OH reactions 

may also occur by abstraction from the C-H bonds in the hydroperoxides but these pathways are 

estimated to be less important than reaction at the hydroperoxide group and are ignored. 

Reactions of the peroxy radicals with other peroxy and acetyl peroxy radicals also need to be 

considered under low NOx conditions, though they are less important than the reactions with HO2

discussed above. These are estimated using the general procedures associated with the SAPRC07 

mechanism, as discussed by Carter (2009a) and shown in Table 3 below. 

The representation of these reactions in SAPRC-07 mechanism is given in Table 2 and Table 3, 

which list the model species and reactions, respectively. Table 2 gives a description of the model species 

used and footnotes to Table 3 indicate the source of the rate constants or parameters used and give 

additional discussion about how the mechanism was estimated or represented. Carter (2009a) should be 

consulted for a more complete discussion of the chemical operators and other species used in the SAPRC07 mechanism. A complete listing of the other reactions used in the SAPRC-07 mechanism for the model 

simulations for this study is given in Appendix A. 

Representation of Chamber Conditions 

The procedures used in the model simulations of the environmental chamber experiments for this 

project are the same as those used by Carter (2009b) for the experiments with trans 1,3,3,3-

tetrafluoropropene and are based on those discussed in detail by Carter (2004) and employed in the 

studies of Carter and Malkina (2005) and Carter et al (2005b), updated for SAPRC-07 as discussed by 

Carter (2009a). Carter (2004) should be consulted for details of the characterization model and chamber 

effects parameters employed. The temperatures used when modeling were the averages of the 

temperatures measured in the reactors, corrected as discussed by Carter (2004). 
13 

Table 2. List of model species added to the base mechanism to represent the atmospheric reactions 

of 2,3,3,3-tetrafluoropropene and its oxidation products 

Name Description 

 

Active Species

 R1234YF 2,3,3,3-tetrafluoropropene 

 CF3COF Trifluoroacetyl fluoride 

 R2F4OOH CF3CF(OOH)CH2OH or CF3CF(OH)CH2OOH formed following the reactions of OH with 

the tetrafluoropropene and reaction of the subsequently formed peroxy radical with HO2. 

 RF4OH CF3CF(OH)CH2OH or isomers formed when peroxy radicals formed following OH + 

tetrafluoropropene reaction reacts by disproportionation with other peroxy radicals. 

Steady State Species

xCF3COF Formation of trifluoroacetyl fluoride from alkoxy radicals formed in peroxy radical 

reactions with NO and NO3 (100% yields) and RO2 (50% yields) 

yRF4OOH Formation of CF3CF(OOH)CH2OH or CF3CF(OH)CH2OOH following RO2 + HO2

reactions. 

The light intensity for the blacklight experiments declines slowly with time when the lights are 

new, though the rate of decline decreases as the lights age (Carter et al, 1995a; Carter, 2004, 2007). The 

characterization of the light intensity for the previous set of reported experiments is discussed by Carter 

(2007), and based on extrapolating the light intensity assignments for the experiments carried out then to 

the current experiments we assign a light intensity corresponding to an NO2 photolysis rate of 0.115 min-1

for the experiments modeled in this report. Model simulations of the control experiments for this and the 

trans 1,3,3,3-tetrafluoropropene project (Carter, 2009b) indicate that this is an appropriate assignment. 

The blacklight spectral distribution given by Carter et al (1995a) was found to be appropriate for the 

blacklights in this chamber and is used when modeling the runs in this chamber using the blacklight light 

source. 

The chamber effects parameters used when modeling the experiments in this chamber were the 

same as those given by Carter (2004) except for the HONO offgasing parameters, which were derived 

based on results of characterization runs carried out in conjunction with these experiments as discussed 

below. As discussed by Carter (2004), the chamber effects model currently used for this chamber 

represents both the chamber radical source and background NOx offgasing by HONO offgasing, whose 

magnitude is determined by the chamber effects parameter RN-I, which is the ratio of the HONO 

offgasing rate to the NO2 photolysis rate. The RN-I parameter that best fits the characterization data tends 

to vary over time depending on the conditions of the chamber, and the results of the characterization 

experiments applicable to modeling the experiments discussed in this report, and the assignment of the 

RN-I values used, are given in the Characterization Results section, below. 

The initial reactant concentrations used in the model simulations were based on the 

experimentally measured values. However, the calibration of the 2,3,3,3-tetrafluoropropene 

measurements were based on calculated amounts of compound injected and the volume of the reactors, 

which were measured by injecting known quantities of CO or NOx, and measuring the CO or NOx using 

instruments that were independently calibrated. 
14 

Table 3. List of reactions and rate constants used to represent the atmospheric reactions of 2,3,3,3-

tetrafluoropropene and its oxidation products 

Rate Parameters [b] Reaction and Products [a] k(298) A Ea 

Refs & 

Notes [c]

OH + R1234YF = xHO2 + RO2C + xHCHO + xCF3COF 

+ yR2F4OOH 

1.05e-12 1 

xCF3COF = CF3COF k is variable parameter: RO2RO 2 

xCF3COF = #2 XC k is variable parameter: RO2XRO 2 

yR2F4OOH = R2F4OOH + #-3 XC k is variable parameter: RO2HO2 2 

yR2F4OOH = RF4OH + #-3 XC k is variable parameter: RO2RO2M 2 

yR2F4OOH = k is variable parameter: RO2RO 2 

R2F4OOH + OH = H2O + CF3COF + HCHO + HO2 5.18e-12 3,4 

R2F4OOH + HV = OH + CF3COF + HCHO + HO2 Phot Set= COOH 4,5 

[a] Format of reaction listing: “=“ separates reactants from products; “#number” indicates stoichiometric 

coefficient, “#coefficient {product list}” means that the stoichiometric coefficient is applied to all the 

products listed. 

[b] Except as indicated, the rate constants are given by k(T) = A · e-Ea/RT, where the units of k and A are 

cm3

 molec-1 s-1, Ea are kcal mol-1, T is oK, and R=0.0019872 kcal mol-1 deg-1. If A and Ea are not 

given then the rate constant is assumed to be temperature independent. The following special rate 

constant expressions are used: 

Phot Set = name: The absorption cross sections and (if applicable) quantum yields for the photolysis 

reaction are given by Carter (2009a), except for "PAA", which are given below. Here, “name” 

indicates the photolysis set used. Photolysis rates used in chamber and ambient simulations are 

given in Table A-3. 

k is variable parameter name: The rate constant is calculated using variable parameters that are 

calculated using concentrations of various species. See Footnotes [c] and [e] to Table A-2 in 

Appendix A for a discussion of the parameters and how they are calculated. 

[c] Footnotes discussing reactions or rate constants used are as follows: 

 1 See text for a discussion of the mechanism. The rate constant is from Nielsen et al (2007). Overall 

organic nitrate formation is assumed to be negligible because this was found to give the best fits 

to the chamber data, as discussed in the Results section. 

 2 See Carter (2009a) and footnotes to Table A-2 for a discussion of the reactions of peroxy radical 

operator species. xCF3COF is the operator that represents the formation of trifluoroacetyl 

fluoride from peroxy radical reactions. YR2F4OOH is the operator that represents the formation 

of tetrafluorohyderoperoxides formed when the peroxy radicals from the OH + tetrafluoropropene 

reactions react with HO2. 

 3 The reaction is assumed to occur primarily with OH abstracting from the OOH group, with a rate 

constant assumed to be the same as used for that process in the reaction of OH with 

methylhydroperoxide (COOH). See Table A-2. 

 4 The alkoxy radicals formed should be the same as those formed in the OH + tetrafluoropropene 

reaction, so the same overall products are assumed to be formed, i.e., HO2 + HCHO + 

trifluoroacetyl fluoride. 

 5 The photolysis is assumed to occur at the same rate as used for methyl hydroperoxide, and the 

products are assumed to be OH + the alkoxy radical. See Carter (2009a). 
15 

Atmospheric Reactivity Simulations 

Atmospheric reactivity model simulations were carried out to derive MIR and other atmospheric 

reactivity values for 2,3,3,3-tetrafluoropropene. The base mechanism, scenarios, and methods used were 

the same as those used when calculating the MIR and other atmospheric ozone reactivity scales for the 

SAPRC-07 mechanism by Carter (2009a), so the atmospheric reactivities calculated for 2,3,3,3-

tetrafluoropropene reactivities in this work are directly comparable with those given by Carter (2009a) for 

the ~1100 other types of VOCs represented using the SAPRC-07 mechanism. The mechanism used for 

2,3,3,3-tetrafluoropropene is the same as gave the best fits to the results of the chamber simulations, as 

discussed in the Results section below, and is given in Table 3, above. The inputs used in the reactivity 

scenarios are described by Carter (1994a,b). 
16 

RESULTS AND DISCUSSION 

A chronological listing of the environmental chamber experiments carried out for this project is 

given in Table 4. These include experiments with 2,3,3,3-tetrafluoropropene and appropriate 

characterization and control experiments needed for the data to be useful for mechanism evaluation. The 

results of the characterization experiments will be discussed first, followed by a discussion of the results 

of the mechanism evaluation experiments and of the model simulations of these experiments. 

Characterization Results 

The individual characterization experiments that are relevant to this project are summarized in 

Table 4. Except as discussed below, the characterization results are consistent with those discussed by 

Carter et al (2005b), Carter and Malkina (2005, 2007), Carter (2007) and Carter (2009b), and the same 

characterization parameters were used for modeling. The only chamber effect parameter that was changed 

when modeling the experiments for this project concerns the apparent HONO offgasing, which is 

believed to be responsible for both the chamber radical source and NOx offgasing effects (Carter, 2004). 

This is represented in the chamber effects model by the parameter RN-I, which is the HONO offgasing 

rate used in the simulations divided by the light intensity as measured by the NO2 photolysis rate. Figure 

3 shows the HONO offgasing parameters that best fit the radical or NOx - sensitive characterization 

experiments carried out in the UCR EPA during the period of the last three sets of reactors. Note that the 

best-fit parameters depend on the mechanism used (particularly the OH + NO2 rate constant), and all 

these were calculated for SAPRC-07, the mechanism used in this work. 

 The experiments carried out for this project start at run EPA966, so the applicable 

characterization data is for the last set of reactors shown on the figure. The average RN-I parameter that 

fit the results of the experiments with this reactor was approximately 10 ppt, and this was used when 

modeling the experiments carried out for this project. Although there is a large amount of scatter in the 

RN-I parameter that gave the best fit to the data in these characterization experiments, it should be noted 

that the simulation of the surrogate - NOx incremental reactivity experiments, which are the experiments 

used for mechanism evaluation, are not very sensitive to this parameter. Test calculations showed that 

variation of this parameter within the range shown on Figure 4 has only a minor effect on the simulations 

of these experiments, and does not affect conclusions concerning the tetrafluoropropene mechanism that 

gives the best fits to the data. 

For modeling purposes, we use the same chamber effects parameters as used by Carter (2004), 

Carter and Malkina (2005), Carter et al (2005b), and Carter (2007) for all the other chamber effect 

parameters. Simulations of the incremental reactivity experiments are also not very sensitive to these 

parameters. 

Other control experiments carried out during this period were two side equivalency tests (with the 

same reactive organic gas surrogate - NOx mixture simultaneously irradiated in both reactors). In addition, 

a propene - NOx control experiment and several pure air runs were carried out previously, and the results 

were as expected. The results of the side equivalency tests indicated acceptable side equivalency and are 

given in Table 5, in conjunction with the results of the reactivity experiments with 2,3,3,3-

tetrafluoropropene, discussed below. 
17 

Table 4. Summary of experiments carried out for this project. 

Run 

[a] Date Type [b] Purpose and Applicable Conditions Results 

966 1/8/09 Surrogate - 

NOx 

Irradiation 

Control for incremental 

reactivity experiments to 

test side equivalency. See 

Table 5 for reactant levels. 

Initial concentrations in the appropriate 

range. Relevant results are summarized 

on Table 5. Good side equivalency 

obtained. 

971 1/19/09 CO - NOx

Irradiation 

Chamber radical source 

characterization. 22 ppb 

NOx and 38 ppm CO 

injected into both reactors 

Results indicated much lower radical 

input rates than generally observed in 

such experiments, but was not 

completely outside the range of 

variability observed previously. See 

Figure 3. 

976 2/21/09 Surrogate - 

NOx + 2,3,3,3-

tetrafluoropropene Irradiation 

Incremental reactivity 

experiment for 2,3,3,3-

tetrafluoropropene. See 

Table 5 for reactant levels. 

Initial concentrations not in the 

appropriate range; NOx levels lower 

than expected and gas ROG surrogate 

levels high because of an injection 

calculation error. No PM data. See 

Table 5 and Figure 4.

981 3/19/09 Surrogate - 

NOx + 2,3,3,3-

tetrafluoropropene Irradiation 

Incremental reactivity 

experiment for 2,3,3,3-

tetrafluoropropene. See 

Table 5 for reactant levels. 

Run ended early because of probable 

leak in reactor. Initial concentrations 

not in the appropriate range; NOx levels 

higher than expected and gas ROG 

surrogate levels high because of an 

injection calculation error. PM data are 

questionable and are not used. See 

Table 5 and Figure 4.

982 3/20/09 CO - Air 

Irradiation 

Chamber NOx offgasing 

characterization. 36 ppm 

CO injected into both 

reactors. 

Results were consistent with chamber 

wall model used for these experiments. 

See Figure 3. 

984 3/26/09 Surrogate - 

NOx + 2,3,3,3-

tetrafluoropropene Irradiation 

Incremental reactivity 

experiment for 2,3,3,3-

tetrafluoropropene. See 

Table 5 for reactant levels. 

Initial concentrations not in the 

appropriate range; gas ROG surrogate 

levels high because of an injection 

calculation error. See Table 5 and 

Figure 4.

985 3/30/09 Surrogate - 

NOx + 2,3,3,3-

tetrafluoropropene Irradiation 

Incremental reactivity 

experiment for 2,3,3,3-

tetrafluoropropene. See 

Table 5 for reactant levels 

Initial concentrations not in the 

appropriate range; gas ROG surrogate 

levels high because of an injection 

calculation error. See Table 5 and 

Figure 4.
Table 4 (continued) 

18 

Run 

[a] Date Type [b] Purpose and Applicable Conditions Results 

986 4/1/09 Surrogate - 

NOx + 2,3,3,3-

tetrafluoropropene Irradiation 

Incremental reactivity 

experiment for 2,3,3,3-

tetrafluoropropene. See 

Table 5 for reactant levels 

Initial concentrations not in the 

appropriate range; gas ROG surrogate 

levels high because of an injection 

calculation error. See Table 5 and 

Figure 4.

990 4/8/09 Surrogate - 

NOx + 2,3,3,3-

tetrafluoropropene Irradiation 

Incremental reactivity 

experiment for 2,3,3,3-

tetrafluoropropene. See 

Table 5 for reactant levels. 

Base case is standard MIR 

conditions 

Initial concentrations in the appropriate 

range. See Table 5 and Figure 4. No 

useable PM data. 

991 4/9/09 Surrogate - 

NOx + perfluorohexane 

Irradiation 

Control for incremental 

reactivity experiments to 

test side equivalency and to 

verify that the addition of 

the perfluoro n-hexane 

dilution tracer does not 

affect reactivity results. 

Standard MIR conditions 

except that 3.5 ppm 

pefluorohexane added to 

Side A. See Table 5 for 

other reactant levels.. 

Initial concentrations in the appropriate 

range. Relevant results are summarized 

on Table 5. Good side equivalency 

obtained. As expected, the presence of 

perfluorohexane did not affect the gasphase results. No useable PM data. 

992 4/10/09 Surrogate - 

NOx + 2,3,3,3-

tetrafluoropropene Irradiation 

Incremental reactivity 

experiment for 2,3,3,3-

tetrafluoropropene. See 

Table 5 for reactant levels. 

Base case is standard MIR 

conditions 

Injected NOx levels lower than intended 

due to injection error . See Table 5 and 

Figure 4.

1000 4/23/09 CO - air 

irradiation and 

halopropene 

light decay test. 

~65 ppm of CO and ~ 1 

ppm each of 2,3,3,3-

tetrafluoropropene, trans 

1,3,3,3-tetrafluoropropene, 

another halogenated 

propene, perfluorohexane 

and n-butane were injected 

into both reactors and 

irradiated. [a] 

The ozone formation in this experiment 

was consistent with that expected using 

the standard chamber characterization 

model. See Figure 3. The fluoropropene 

results indicated that concentrations of 

2,3,3,3-tetrafluoropropene decline at the 

same rates as CO and n-butane, which 

is attributable to dilution. However, the 

added trans 1,3,3,3-tetrafluoropropene 

and another halopropene declined in the 

reactor slightly faster than can be 

accounted for gas-phase processes. 

1004 5/3/09 CO - NOx

Irradiation 

40 ppb of CO and 20 ppb 

of NOx and ~50 ppb 

perfluorohexane injected 

into both reactors. 

The NO oxidation rate in this 

experiment was in the range expected 

using the standard chamber 

characterization model. See Figure 3. 
Table 4 (continued) 

19 

Run 

[a] Date Type [b] Purpose and Applicable Conditions Results 

1005 5/4/09 Surrogate - 

NOx + 2,3,3,3-

tetrafluoropropene Irradiation 

Incremental reactivity 

experiment for 2,3,3,3-

tetrafluoropropene. See 

Table 5 for reactant levels. 

Base case is standard MIR 

conditions. 

Run had to be ended just after 5 hours 

because of leakage in base case reactor. 

Initial concentrations in the appropriate 

range. M-Xylene data for test 

experiment, and therefore IntOH 

reactivity data, questionable and 

inconsistent with data from other GC 

instruments. See Table 5 and Figure 4. 

[a] Gaps in run number indicate experiments whose data were not useful for this project.. 

[b] All experiments are ~6-hour irradiations using blacklights. "Surrogate" indicates a ROG surrogate - 

NOx mixture irradiated; "MIR" and "MOIR/2" mean the target initial NOx and base ROG surrogate 

were 30 ppb and 0.55 ppmC and 25 ppb and 1.1 ppmC, respectively. "Incremental Reactivity" 

indicates that a reactant was added to one of the two reactors. 

[c] The purpose of injecting the n-butane and halopropenes was to test whether consumption of 

halopropenes occur at faster rates in this reactor than can be accounted for by gas-phase processes. 

Loss of these compounds by reaction with OH radicals is calculated to be negligible under the 

conditions of these experiments. The n-butane was injected as a control and dilution tracer because it 

is known not to have unknown loss processes and can be analyzed with precision. The 

perfluorohexane data were not useful as a tracer because of GC interferences.

0

5

10

15

20

500 550 600 650 700 750 800 850 900 950 1000

EPA Run Number

HONO Input Parameter (RN-I) (ppt)

Radical sensitive (Side A)

Radical sensitive (Side B)

NOx sensitive (Side A)

NOx sensitive (Side B)

Humidified

Used in Model

Replaced Reactors

Figure 3. Plots of best fit HONO offgasing parameters against UCR EPA run number. 
20 

Incremental Reactivity and Mechanism Evaluation Results 

The conditions and selected results of the incremental reactivity experiments used to evaluate the 

2,3,3,3-tetrafluoropropene mechanism are summarized on Table 5. These experiments consist of 

irradiations of a reactive organic gas (ROG) - NOx mixture serving as a simplified model of the chemical 

system involved on O3 formation in urban atmospheres, together in irradiations of the same mixture with 

2,3,3,3-tetrafluoropropene (the test compound) added. The experiment without the added test compound 

is referred to as the "base case" experiment, and the experiment where the test compound is added is the 

"test" experiment. The differences in O3 formation and other measures of reactivity in these experiments 

provide a measure of the effects of the test compound in a system more closely representing atmospheric 

conditions than the simpler experiments discussed above, and provide a more realistic test of the 

mechanism's ability to predict its atmospheric reactivity. 

As in previous incremental reactivity experiments carried out in this chamber (Carter and 

Malkina, 2005, 2007; Carter et al, 2005b), the plan for this project was to carry out two types of base case 

experiments. The first is a lower ROG/NOx experiment designed to approximate conditions where O3

formation is most sensitive to VOC emissions, which serve as the basis for the MIR reactivity scale, and 

are referred to as "MIR" experiments. The second is at higher ROG/NOx ratios with NOx levels at 

approximately half that yielding maximum ozone concentrations, and are referred to as "MOIR/2" 

experiments. For the MIR experiments the target initial NOx was approximately 30 ppb and the target 

initial base case ROG was approximately 0.6 ppmC, while for the MOIR/2 experiments the target initial 

levels were approximately 25 ppb and 2.3 ppmC, respectively. In both cases, the base ROG surrogate 

mixture representing reactive organic gases from all sources consists of n-butane, n-octane, ethene, 

propene, trans-2-butene, toluene and m-xylene, and is based on a mixture derived previously (Carter et al, 

1995b) as a simplification of ambient mixtures used in the atmospheric reactivity calculations. Earlier 

versions of this mixture also contained formaldehyde, but this was not included in the current experiments 

for experimental reasons. As discussed by Carter and Malkina (2005), this does not significantly affect 

the utility of the experiments for mechanism evaluation. 

Although the plan for the project was to carry out several MIR and MOIR/2 experiments, 

problems were encountered in the calculations of injections or the injection procedures for many of the 

experiments, resulting in initial concentrations being different than those intended. These cases are noted 

where applicable in Table 4 and Table 5. Since the injection errors were applicable for both the base case 

and the added test compound side, these experiments were still valid as incremental reactivity 

experiments. Although these experiments did not have the desired initial base case ROG and/or NOx

levels, they were still useful for mechanism evaluation because the variability in initial reactant 

concentrations are taken into account in the model calculations The net effect of including these 

experiments is that the mechanism is evaluated under a wider range of conditions than would otherwise 

be the case. The experiments modeled include one MIR experiment and a number of experiments with 

lower ROG/NOx levels, so the conditions intended to be used in the project plan are included. 

The measures of gas-phase reactivity used to evaluate the mechanisms in the incremental 

reactivity experiments are the effects of the test compound on ∆([O3]-[NO]), or ([O3]t-[NO]t)-([O3]0-

[NO]0), and IntOH, the integrated OH radical levels. As discussed elsewhere (e.g., Johnson, 1983; Carter 

and Atkinson, 1987; Carter and Lurmann, 1991, Carter et al, 1993), ∆([O3]-[NO]) gives a direct measure 

of the amount of conversion of NO to NO2 by peroxy radicals formed in the photooxidation reactions, 

which is the process that is directly responsible for ozone formation in the atmosphere. This gives a useful 

measure of factors affecting O3 reactivity even early in the experiments where O3 formation is suppressed 

by the unreacted NO. Although this is the primary measure of the effect of the VOC on O3 formation, the 
21 

Table 5. Summary of initial concentrations and selected gas-phase results of the incremental 

reactivity experiments. 

Base Run Initial 

Concentrations 5 Hr O3 (ppb) D([O3]-[NO]) 

Change (ppb) 

IntOH 

change 

5 Hr PM 

(μg/m3

) EPA 

Run 

No. 

Test 

Side 

Test 

Cmpd 

Added 

(ppm) 

NOx

(ppb) 

ROG 

(ppmC) Base Test 2 Hr 5 Hr (pptmin) Base Test 

Side Equivalency or added Perfluorohexane Experiments 

966 A 22 1.23 89 89 3 0 0 0.36 0.31 

991 A 3.49 [a] 33 0.54 37 37 1 0 1 [b] [b] 

Added 2,3,3,3-Tetrafluoropropene Experiments (in order of increasing base case ROG/NOx) 

1005 A 2.12 32 0.54 29 111 33 -46 18 [b] [b] 

990 B 1.82 33 0.64 52 125 37 73 [b] [b] [b] 

986 B 2.18 34 1.44 [c] 117 152 34 34 -4 0.01 0.01 

985 B 1.12 25 1.54 [c] 107 122 10 15 -3 0.05 0.04 

981 B 1.26 41 2.61 [c] [b] [b] 14 [b] [b] [b] [b] 

992 A 2.37 15 [d] 1.06 72 101 22 29 -7 0.23 0.02 

976 A 1.05 13 [d] 1.31 [c] 82 95 8 10 -2 0.11 0.04 

984 B 1.11 23 3.13 [c] 91 98 3 7 0 0.26 0.26 

[a] Run carried out with added prefluorohexane to verify that this compound is unreactive and its 

presence would not affect reactivity results. 

[b] No useable data obtained or experiment ended before 5 hours. 

[c] Gaseous base ROG components (ethene, propene, and trans-2-butene) high by a factor of 3.6 due to 

reactant injection calculation error. 

[c] Initial NOx levels lower than intended due to NOx injection problems. 

effect on radical levels is also a useful measure for mechanism evaluation, because radical levels affect 

how rapidly all VOCs present, including the base ROG components, react to form ozone. 

The integrated OH radical levels are not measured directly, but can be derived from the amounts 

of consumption of reactive VOCs that react only with OH radical levels. In particular, 

tracer

0 t

t kOH

ln([tracer] [tracer] ) Dt IntOH − = (I) 

where [tracer]0 and [tracer]t are the initial and time t concentrations of the compound used as the OH 

tracer, kOHtracer its OH rate constant, and D is the dilution rate in the experiments. The latter is neglected 

in our IntOH analysis. The base ROG surrogate component m-xylene was used as the tracer to derive the 

IntOH levels in these experiments. The OH + m-xylene rate constant used was 2.36 x 10-11 cm3

 molec-1 s-1

(Atkinson, 1989). 

Plots of experimental ∆([O3]-[NO]) in the base case and test experiments, changes in 

∆([O3]-[NO]) and IntOH caused by adding the 2,3,3,3-tetrafluoropropene, are shown on Figure 4 and 

changes in these quantities are also summarized on Table 5. It can be seen that the addition of the 

tetrafluoropropene caused a measurable increase in NO oxidation and O3 formation in all the experiments, 

though the increase was small in some of the experiments with high ROG/NOx ratios and lower amount 

of test compound added. The effect of adding a given amount of the tetrafluoropropene on ∆([O3]-[NO]) 
22 

EPA1005A EPA990B EPA986B EPA985B

(2.1 ppm added) (1.8 ppm added) (2.2 ppm added) (1.1 ppm added)

∆(O3-NO) (ppm) vs Hour

IR ∆(O3-NO) (mole basis) vs Hour

IR IntOH (ppt-min/ppm) vs Hour

n-C6F14 (ppm) vs Hour

2,3,3,3-Tetrafluoropropene (ppm) vs Hour

0.00

0.04

0.08

0.12

0.16

0123456

0.00

0.01

0.02

0.03

0.04

0.05

0123456

-2

-1

0

1

2

0123456

0.00

0.05

0.10

0.15

0.20

0123456

0.000

0.005

0.010

0.015

0.020

0.025

0123456

-3

-2

-1

0

1

0123456

0.00

0.04

0.08

0.12

0.16

0123456

0.000

0.005

0.010

0.015

0.020

0123456

-4

-3

-2

-1

0

1

0123456

0.00

0.05

0.10

0.15

012345

0.00

0.01

0.02

0.03

0.04

0.05

012345

-4

0

4

8

012345

Questionable 

data after

2 hrs.

Base Experiment Test Experiment B

Model Used 5% Nitrate calc

0.0728

0.0730

0.0732

0.0734

0123456

0.067

0.068

0.069

0.070

0.071

0123456

0.075

0.076

0.077

0.078

0123456

0.061

0.062

0.063

0.064

012345

1.72

1.76

1.80

1.84

0123456

2.04

2.08

2.12

2.16

2.20

0123456

1.06

1.08

1.10

1.12

1.14

0123456

2.04

2.08

2.12

012345

Figure 4a. Experimental and calculated results of the incremental reactivity experiments with added 

2,3,3,3-tetrafluoropropene (part 1 of 2). 
23 

EPA981B EPA992A EPA976A EPA984B

(1.3 ppm added) (2.4 ppm added) (1.0 ppm added) (1.1 ppm added)

∆(O3-NO) (ppm) vs Hour

IR ∆(O3-NO) (mole basis) vs Hour

IR IntOH (ppt-min/ppm) vs Hour

n-C6F14 (ppm) vs Hour

2,3,3,3-Tetrafluoropropene (ppm) vs Hour

0.00

0.05

0.10

0.15

0.20

01234

-0.01

0.00

0.01

0.02

01234

-2

-1

0

1

2

01234

0.00

0.04

0.08

0.12

0123456

0.000

0.004

0.008

0.012

0.016

0123456

-4

-3

-2

-1

0

1

0123456

0.00

0.04

0.08

0.12

0123456

0.000

0.004

0.008

0.012

0.016

0123456

-4

-2

0

2

4

0123456

0.00

0.04

0.08

0.12

0123456

-0.004

0.000

0.004

0.008

0.012

0123456

-2

-1

0

1

2

0123456

Base Experiment Test Experiment B

Model Used 5% Nitrate calc

0.0

0.2

0.4

0.6

0.8

1.0

01234

Not Present

0.071

0.072

0.073

0.074

0123456

0.0

0.2

0.4

0.6

0.8

1.0

0123456

Not Present

0.091

0.092

0.093

0.094

0123456

Not Present on 

Test Side

1.20

1.22

1.24

1.26

1.28

01234

No dilution 

tracer present

2.28

2.30

2.32

2.34

2.36

2.38

0123456

1.030

1.035

1.040

1.045

1.050

0123456

No tetrafluoropropene 

consumption 

data 1.06

1.08

1.10

1.12

0123456

No dilution 

tracer present

Figure 4b Experimental and calculated results of the incremental reactivity experiments with added 

2,3,3,3-tetrafluoropropene (part 2 of 2). 
24 

was larger in the MIR experiment than the lower NOx runs, which is expected since MIR conditions are 

generally more sensitive to most VOCs. 

The effects of the added tetrafluoropropene on the integrated OH levels in the experiments were 

relatively low, though generally negative. This indicates that this compound has a tendency to inhibit 

radical levels in the experiments, though the effect is small. Many VOCs have a tendency to inhibit 

overall radical levels in experiments to varying degrees. 

Results of model simulations of the incremental reactivity experiments are also shown on Figure 

4. For most experiments the model simulated the ∆([O3]-[NO]) results of the base case experiment quite 

well. The best fits to the ∆([O3]-[NO]) incremental reactivity data were obtained if it is assumed that no 

nitrate formation occurs in the overall reaction, as shown with the solid line ("model used") curves on 

Figure 4. It is assumed that overall nitrate formation occurs with a ~5% yield, which gives best fits to the 

data for trans 1,3,3,3-tetrafluoropropene (Carter, 2009b), then the model has a small but consistent bias 

towards underpredicting ∆([O3]-[NO]) reactivities, as shown by the dashed lines on Figure 4. Changing 

the overall nitrate yield has no significant effect on calculations of IntOH reactivity or the rates of 

tetrafluoropropene consumption. 

Figure 4 also shows the experimental and model calculated data for the consumption of the 

2,3,3,3-tetrafluoropropene during the experiment. In all cases the consumption of this compound was 

relatively slow and the fractions reacted were low. Because even relatively low levels of reactor dilution 

would affect consumption data for such slowly reacting compounds, in most experiments we added 

perfluoro n-hexane as a tracer to determine dilution rates to use when modeling these experiments. The 

results indicated that some dilution was occurring in some experiments but not in others, though the 

dilution rates were never greater than 0.5% per hour. Although small, this level of dilution did have an 

effect on the model simulations of the tetrafluoropropene consumption rate, so dilution rates adjusted to 

fit the perfluorohexane data were used when modeling runs where perfluorohexane data were available. 

Figure 4 shows that even after correcting for dilution the model still had a slight tendency to 

underpredict the consumption rates of 2,3,3,3-tetrafluoropropene to a slight extent for most of the 

experiments. However, this underprediction was also seen for n-butane, which is present in all 

experiments as a base ROG surrogate, and which also reacts relatively slowly (though with a rate constant 

that is about 2.3 times higher than the tetrafluoropropene. The consumption rate of the tetrafluoropropene 

relative to n-butane, after correction for dilution in most cases, agreed very well with the rate constant 

ratios for these two compounds, indicating that this underprediction is not a problem with the rate 

constants used in the mechanisms. It is apparently due to the model somewhat underpredicting OH levels 

in the experiments. Since the model gives reasonably good fits to the IntOH reactivity, this 

underprediction must be occurring to the same extent in the base case experiments, and indicates a 

problem with the base mechanism, not the mechanism for the 2,3,3,3-tetrafluoropropene. 

Measurements of particle formation were also made during the course of the experiments, using 

the procedures discussed above and by Carter et al (2005b), and representative results are summarized on 

Table 5. The addition of the 2,3,3,3-tetrafluoropropene was found to have either no measurable effect on 

PM formed or to decrease PM formed in the experiments, indicating that this compound is not a 

significant source of secondary organic aerosol (SOA). This is not unexpected, since the mechanism 

derived for this compound does not involve formation of low volatility products. Slight inhibiting effects 

on SOA is similar to what Carter et al (2005a) observed for ethylene and propylene glycols, and is 

attributed to the slightly negative effects of these compounds on overall radical levels, which causes less 

SOA formation from the base ROG surrogate components. 
25 

Atmospheric Reactivity Calculation 

Conditions and maximum O3 concentrations of the ambient scenarios used for reactivity 

assessment are summarized on Table 6. These are the same scenarios as used to calculate the atmospheric 

reactivities of the ~1100 types of VOCs using the SAPRC-07 mechanism by Carter (2009a), and are also 

the same as used in previous reactivity scales calculated using the SAPRC-99 (Carter, 2000a), and 

SAPRC-90 (Carter, 1994a) mechanisms. All of these are 1-day box model scenarios with varying 

inversion heights, initially present and emitted NOx and reactive organics, and O3 and background VOCs 

entrained from aloft as the inversion heights increase during the day (Carter, 1994a,b), with inputs 

designed to represent various urban areas around the United States (Baugues, 1990). As discussed 

previously, four types of scenarios are employed. 

• Base. The base case scenarios have the NOx and other inputs as originally specified by Baugues 

(1990) to represent the various urban areas around the United States. Note that these are not good 

representations of current conditions, since generally these scenarios predict much higher O3

levels than currently occur, and these box model incorporate significant simplifications of 

transport, mixing, and emissions, and multi-day effects, which can be important. However, they 

do represent a variety of chemical conditions, which are the main factors reflecting relative

atmospheric reactivities of VOCs. These scenarios represent a variety of relative NOx levels, 

which is a major factor affecting absolute and relative reactivities of VOCs (Carter and Atkinson, 

1989; Carter, 1994a). For this reason, other types of scenarios, discussed below, are derived to 

represent standard conditions of NOx availability. 

• MIR. The Maximum Incremental Reactivity (MIR) scenarios have the NOx inputs adjusted so 

that the base ROG mixture used to represent all the anthropogenic VOC emissions has the 

maximum incremental reactivity relative to ozone formation. All the other inputs are the same as 

in the base case scenarios. Although the base ROG reactivity is used to define the MIR NOx level, 

most other types of VOCs also have their maximum incremental reactivity at this same NOx level. 

These scenarios represent the relatively high NOx conditions where O3 formation is the most 

sensitive to VOC emissions. The averages incremental reactivities in all these scenarios are used 

to derive the MIR scale that is used in regulatory applications in California (CARB 1993, 2000). 

• MOIR. The Maximum Ozone Incremental Reactivity (MOIR) scenarios have the NOx inputs 

adjusted to give the maximum daily maximum ozone concentration. All other inputs are the same 

as in the base and MIR scenarios. These scenarios represent NOx conditions that are optimum for 

O3 formation, which is always lower than those for MIR. The averages incremental reactivities in 

all these scenarios are used to derive the MOIR scale, which can be considered as an alternative 

to MIR (Carter, 1994a). 

• EBIR. The Equal Benefit Incremental Reactivity (EBIR) scenarios have the NOx inputs adjusted 

so that O3 formation is equally sensitive to changes in total ROG or NOx inputs. All the other 

inputs are the same as in the base, MIR, and MOIR scenarios. The NOx inputs are always lower 

than those yielding maximum O3 (MOIR), and represent the lowest NOx levels where VOC 

control is at least as effective as NOx control. The averages incremental reactivities in all these 

scenarios are used to derive the EBIR scale, which is a useful complement to the MIR scale in 

assessing how NOx levels affect relative reactivities. 

• Averaged Conditions. The averaged conditions scenarios have all inputs other than total NOx

derived to represent the average for the base case scenarios. The NOx inputs are varied to assess 

how measures of reactivity depend on NOx with other inputs held constant. Incremental 

reactivities in the MIR, MOIR, and EBIR averaged conditions scenarios (i.e., whose NOx inputs 

are adjusted to represent those respective conditions) usually give good approximations to 

reactivities in those respective scales, though they are not used in deriving these scales. 
26 

Table 6. Summary of conditions of scenarios used for reactivity assessment 

Max O3 (ppb) ROG / NOx 

Scenario 

Base MIR MOIR EBIR Base MIR MOIR EBIR

Max 

Height 

(kM) 

ROG 

input 

(m.mol 

m-2) 

O3 aloft 

(ppb) 

Final H 

(m) 

Averaged 

Conditions 178 225 211 3.9 5.9 9.1 1.8 15 70 1823 

Atlanta, GA 171 144 176 168 7.3 3.7 5.6 7.9 2.1 12 63 2146 

Austin, TX 170 153 185 175 9.3 3.5 5.4 8.2 2.1 11 85 2108 

Baltimore, MD 310 243 318 293 5.2 4.0 6.2 10.1 1.2 17 84 1169 

Baton Rouge, LA 234 185 234 224 6.8 4.5 6.6 8.7 1.0 11 62 968 

Birmingham, AL 238 203 257 242 6.9 2.8 4.3 6.4 1.8 13 81 1770 

Boston, MA 191 164 199 189 6.5 2.9 4.4 6.8 2.6 14 105 2598 

Charlotte, NC 139 137 162 158 7.8 1.9 3.0 4.1 3.0 7 92 3046 

Chicago, IL 284 241 320 299 11.6 4.4 6.6 9.9 1.4 25 40 1392 

Cincinnati, OH 195 158 197 182 6.4 3.5 5.3 9.1 2.8 17 70 2816 

Cleveland, OH 241 194 241 228 6.6 4.4 6.9 10.3 1.7 16 89 1650 

Dallas, TX 184 160 202 192 4.7 4.2 6.4 9.2 2.3 18 75 2250 

Denver, CO 193 161 199 187 6.3 5.0 7.6 11.6 3.4 29 57 3358 

Detroit, MI 235 183 238 218 6.8 3.8 5.8 10.0 1.8 17 68 1844 

El Paso, TX 175 144 175 168 6.6 4.6 7.2 10.0 2.0 12 65 2000 

Hartford, CT 167 145 184 173 8.4 2.9 4.5 7.3 2.3 11 78 2318 

Houston, TX 298 226 298 277 6.1 4.1 6.2 9.5 1.7 25 65 1748 

Indianapolis, IN 202 156 203 191 6.6 4.0 6.5 9.8 1.7 12 52 1675 

Jacksonville, FL 149 126 156 149 7.6 3.7 5.5 7.6 1.5 8 40 1485 

Kansas City, MO 151 126 158 146 7.1 3.1 4.9 8.5 2.2 9 65 2200 

Lake Charles, LA 288 229 305 291 7.4 3.6 5.3 7.2 0.5 7 40 457 

Los Angeles, CA 558 403 559 528 7.6 5.2 8.0 11.2 0.5 23 100 503 

Louisville, KY 201 162 202 192 5.5 3.3 5.1 7.4 2.5 14 75 2518 

Memphis, TN 223 178 231 216 6.8 3.4 5.1 7.8 1.8 15 58 1750 

Miami, FL 129 120 149 143 9.6 2.9 4.5 6.4 2.7 9 57 2720 

Nashville, TN 161 146 186 175 8.0 2.6 4.0 6.0 1.6 7 50 1608 

New York, NY 372 302 378 357 8.1 4.8 6.7 9.8 1.5 39 103 1512 

Philadelphia, PA 234 178 234 218 6.2 4.1 6.3 9.7 1.8 19 53 1800 

Phoenix, AZ 267 208 267 244 7.6 5.0 7.8 13.0 3.3 40 60 3250 

Portland, OR 159 131 163 156 6.5 3.1 4.9 7.0 1.6 6 66 1575 

Richmond, VA 231 181 233 214 6.2 3.6 5.5 9.4 1.9 16 64 1932 

Sacramento, CA 195 150 196 183 6.6 3.9 6.0 9.1 1.1 7 60 1103 

St Louis, MO 304 237 311 288 6.1 4.7 7.2 11.6 1.6 26 82 1625 

Salt Lake City, UT 180 156 189 177 8.5 3.5 5.5 9.1 2.2 11 85 2150 

San Antonio, TX 119 101 122 118 3.9 3.0 4.7 6.5 2.3 6 60 2308 

San Diego, CA 185 146 185 177 7.1 4.7 7.2 10.1 0.9 8 90 850 

San Francisco, CA 225 345 455 434 4.8 6.1 9.0 12.0 0.7 25 70 650 

Tampa, FL 212 172 218 209 4.4 3.5 5.2 7.0 1.0 8 68 991 

Tulsa, OK 219 171 219 202 5.3 3.5 5.4 8.8 1.8 15 70 1830 

Washington, DC 272 209 273 256 5.3 3.2 4.8 7.4 1.4 13 99 1421 
27 

Table 7 gives the calculated incremental reactivities for 2,3,3,3-tetrafluoropropene in these 

various scenarios. These were calculated using the mechanism that gave the best fit to the chamber data, 

i.e. with the nitrate yield set at 5% (see Table 3). The calculated incremental reactivities for ethane, the 

compound that has been used by the U.S. EPA as the informal standard to define "negligible" ozone 

impact for the purpose of exempting VOCs from regulation as ozone precursors (Dimitriades, 1999), are 

also shown on the table. Plots of the incremental reactivities of 2,3,3,3-tetrafluoropropene relative to 

ethane against relative NOx levels are shown on Figure 5 

It can be seen that although its incremental reactivities of 2,3,3,3-tetrafluoropropene are always 

positive, they are relatively low, and are comparable, on a mass basis, to those for ethane. The reactivity 

relative to ethane shows relatively little variability from scenario to scenario, with the mass-based 

reactivity ratio for all scenarios being 0.9±0.2. The reactivity ratio for the MIR scenarios is slightly higher 

being 1.04±0.13, but the reactivities of these two compounds are still well within the variability from 

scenario to scenario. 

0.00

0.25

0.50

0.75

1.00

1.25

1.50

0.0 0.5 1.0 1.5 2.0 2.5 3.0

NOx input / MOIR NOx Input

2,3,3,3-Tetrafluoropropene /

Ethane Reactivity (mass basis)

Base

MIR

MOIR

EBIR

Figure 5. Plots of reactivities of 2,3,3,3-tetrafluoropropene relative to ethane against relative NOx

levels for all the scenarios used for reactivity assessment. 
28 

Table 7. Calculated atmospheric incremental reactivities for 2,3,3,3-tetrafluoropropene and 

ethane. 

2,3,3,3-Tetrafluoropropene 

Incremental Reactivity 

(gm O3 / gm VOC) 

 Ethane Incremental Reactivity 

Scenario (gm O3 / gm VOC) 

Base MIR MOIR EBIR Base MIR MOIR EBIR 

Averaged Conditions 0.273 0.152 0.103 0.268 0.184 0.130 

Reactivity Scale Value 

(Scenario averages)

0.135 

±0.035 

0.267 

±0.047 

0.151 

±0.025 

0.104 

±0.018 

0.162 

±0.043 

0.264 

±0.065 

0.184 

±0.051 

0.133 

±0.038 

Atlanta, GA 0.121 0.266 0.159 0.112 0.140 0.252 0.179 0.129 

Austin, TX 0.103 0.268 0.162 0.112 0.132 0.276 0.208 0.146 

Baltimore, MD 0.179 0.256 0.136 0.091 0.208 0.254 0.178 0.128 

Baton Rouge, LA 0.131 0.232 0.139 0.097 0.123 0.196 0.129 0.090 

Birmingham, AL 0.110 0.325 0.171 0.117 0.173 0.351 0.245 0.183 

Boston, MA 0.112 0.259 0.152 0.109 0.155 0.276 0.201 0.149 

Charlotte, NC 0.087 0.272 0.172 0.134 0.124 0.306 0.242 0.199 

Chicago, IL 0.078 0.255 0.133 0.089 0.089 0.239 0.149 0.104 

Cincinnati, OH 0.135 0.279 0.159 0.106 0.206 0.306 0.229 0.165 

Cleveland, OH 0.150 0.236 0.143 0.097 0.164 0.217 0.158 0.115 

Dallas, TX 0.230 0.237 0.139 0.094 0.236 0.232 0.165 0.116 

Denver, CO 0.184 0.231 0.138 0.096 0.156 0.184 0.123 0.086 

Detroit, MI 0.125 0.268 0.144 0.095 0.188 0.288 0.206 0.148 

El Paso, TX 0.158 0.229 0.140 0.097 0.145 0.186 0.132 0.094 

Hartford, CT 0.111 0.302 0.176 0.120 0.166 0.322 0.247 0.183 

Houston, TX 0.145 0.269 0.141 0.093 0.188 0.277 0.185 0.128 

Indianapolis, IN 0.159 0.289 0.163 0.111 0.191 0.280 0.194 0.138 

Jacksonville, FL 0.119 0.297 0.169 0.120 0.122 0.270 0.174 0.123 

Kansas City, MO 0.131 0.308 0.174 0.116 0.206 0.345 0.256 0.183 

Lake Charles, LA 0.109 0.321 0.162 0.113 0.109 0.296 0.166 0.112 

Los Angeles, CA 0.092 0.164 0.082 0.056 0.088 0.139 0.082 0.061 

Louisville, KY 0.172 0.325 0.189 0.131 0.228 0.338 0.245 0.176 

Memphis, TN 0.128 0.327 0.168 0.113 0.165 0.329 0.209 0.148 

Miami, FL 0.093 0.297 0.173 0.126 0.108 0.289 0.202 0.153 

Nashville, TN 0.114 0.398 0.211 0.143 0.172 0.450 0.310 0.222 

New York, NY 0.094 0.207 0.115 0.080 0.075 0.158 0.091 0.065 

Philadelphia, PA 0.145 0.269 0.143 0.097 0.177 0.265 0.175 0.124 

Phoenix, AZ 0.144 0.249 0.139 0.086 0.194 0.261 0.190 0.131 

Portland, OR 0.134 0.294 0.174 0.126 0.172 0.295 0.215 0.161 

Richmond, VA 0.136 0.277 0.152 0.102 0.188 0.278 0.201 0.146 

Sacramento, CA 0.141 0.303 0.160 0.105 0.191 0.307 0.208 0.146 

St Louis, MO 0.159 0.226 0.123 0.083 0.171 0.211 0.144 0.103 

Salt Lake City, UT 0.114 0.268 0.163 0.108 0.168 0.285 0.222 0.159 

San Antonio, TX 0.192 0.240 0.149 0.110 0.223 0.247 0.186 0.140 

San Diego, CA 0.110 0.176 0.108 0.078 0.099 0.143 0.097 0.070 

San Francisco, CA 0.112 0.154 0.091 0.064 0.085 0.113 0.071 0.051 

Tampa, FL 0.221 0.294 0.160 0.115 0.209 0.263 0.160 0.113 

Tulsa, OK 0.167 0.301 0.164 0.111 0.209 0.307 0.208 0.146 

Washington, DC 0.133 0.266 0.147 0.102 0.186 0.279 0.199 0.148 
29 

CONCLUSIONS 

This project has been successful in obtaining information needed to reduce uncertainties in 

estimating atmospheric ozone impacts of 2,3,3,3-tetrafluoropropene. The available kinetic and 

mechanistic data for this compound are sufficient to derive an atmospheric reaction mechanism for this 

compound that can be used to estimate its atmospheric ozone impacts. However, the mechanism had 

uncertainties and estimates that needed to be tested, and experimental data were needed to establish the 

predictive capability of the mechanism before its predictions can be used as a basis for VOC exemption 

decisions. The experiments carried out for this project were successful in establishing the predictive 

capability of the mechanism developed for this compound, though some adjustments had to be made in 

order for the mechanism to simulate the data. These adjustments were well within the uncertainty of the 

estimates, so the mechanism can now be considered to be reasonably well established. 

The evaluated mechanism predicted that the ozone impacts of 2,3,3,3-tetrafluoropropene, on a 

mass basis are essentially the same as those for ethane. The reactivities relative to ethane averaged 

0.9±0.2 for all scenarios considered, and 1.0 ±0.1 for the MIR scenarios, i.e. well within the scenario-toscenario variability of being the same. Note that all the scenarios considered are one-day simulations, and 

compounds that react in the atmosphere more slowly than ethane might have higher relatively higher 

ozone impacts in multi-day simulations. However, 2,3,3,3-tetrafluoropropene reacts somewhat more 

rapidly than ethane in the atmosphere, so if anything its ozone impacts relative to ethane are more likely 

to decrease in multi-day simulations. Therefore, if ethane is used as the standard to define “negligible” 

ozone impact for the purpose of determining VOC exemptions for ozone precursors, then 2,3,3,3-

tetrafluoropropene should meet this standard. 

The uncertain portion of the 2,3,3,3-tetrafluoropropene mechanism that had to be adjusted to 

yield satisfactory simulations of the chamber data concerned the nitrate yields in the reaction of NO with 

the initially formed HOC3F4H2OO· peroxy radicals. The overall nitrate yield was previously estimated to 

be negligible (Carter, 2008b), and indeed this mechanism that gave best fits to the data in this study, so it 

was not modified as a result of this experimental study. However, the data for trans 1,3,3,3-

tetrafluoropropene were best fit if an overall nitrate yield of ~5% was assumed (Carter, 2009b), 

suggesting that this should have been the case for 2,3,3,3-tetrafluoropropene as well. The fact that the best 

fit mechanisms suggest different nitrate yields for these tetrafluoropropenes suggest that the position of 

the fluorine atoms on the molecule has an effect on the overall nitrate yields in the photooxidation 

mechanism. Note, however, that these yields are derived indirectly based on modeling ozone reactivity, 

and not direct measurements of nitrate formation. 

The near-explicit mechanism developed for this compound permits predictions of the gas-phase 

products formed in the atmospheric oxidations of 2,3,3,3-tetrafluoropropene. In the case of this compound 

the major products expected are formaldehyde, trifluoroacetyl fluoride, and the fluorinated 

hydroperoxides CF3CF(OH)CH2OOH and CF3CF(OOH)CH2OH, which are expected to react primarily to 

form formaldehyde and trifluoroacetyl fluoride. The formaldehyde will be primarily oxidized to CO and 

CO2, but the trifluoroacetyl fluoride is expected to be relatively stable in the gas phase, though it 

presumably will eventually hydrolyze in the environment to HF and trifluoroacetic acid. The mechanism 

developed in this work could be used for modeling the formation of these products. 

Although this was outside the stated scope of this project, data were also obtained in this project 

concerning the effects of 2,3,3,3-tetrafluoropropene on atmospheric particle formation. The results 

indicated that the addition of this compound to atmospheric reactive organic gas surrogate - NOx

irradiations either had no effect on the mass or particles formed, or slightly reduced it. This indicates that 
30 

this compound does not form measurable amounts of secondary organic aerosol. This is as expected, 

since it is not predicted to form low volatility products. Furthermore, the products that it forms apparently 

do not also undergo significant heterogeneous reactions to form condensable compounds, at least under 

the relatively clean and dry conditions of these experiments. 
31 

REFERENCES 

Atkinson, R. (1989): “Kinetics and Mechanisms of the Gas-Phase Reactions of the Hydroxyl Radical with 

Organic Compounds,” J. Phys. Chem. Ref. Data, Monograph no 1. 

Atkinson, R. (1991): “Kinetics and Mechanisms of the Gas-Phase Reactions of the NO3 Radical with 

Organic Compounds,” J. Phys. Chem. Ref. Data, 20, 459-507. 

Atkinson, R. (1997): "Gas Phase Tropospheric Chemistry of Volatile Organic Compounds: 1. Alkanes 

and Alkenes," J. Phys. Chem. Ref. Data, 26, 215-290. 

Baugues, K. (1990): "Preliminary Planning Information for Updating the Ozone Regulatory Impact 

Analysis Version of EKMA," Draft Document, Source Receptor Analysis Branch, Technical 

Support Division, U. S. Environmental Protection Agency, Research Triangle Park, NC, January. 

CARB (1993): “Proposed Regulations for Low-Emission Vehicles and Clean Fuels -- Staff Report and 

Technical Support Document,” California Air Resources Board, Sacramento, CA, August 13, 

1990. See also Appendix VIII of “California Exhaust Emission Standards and Test Procedures for 

1988 and Subsequent Model Passenger Cars, Light Duty Trucks and Medium Duty Vehicles,” as 

last amended September 22, 1993. Incorporated by reference in Section 1960. 

CARB (2000): “Initial Statement of Reasons for the Proposed Amendments to the Regulation for 

Reducing Volatile Organic Compound Emissions from Aerosol Coating Products and Proposed 

Tables of Maximum Incremental Reactivity (MIR) Values, and Proposed Amendments to Method 

310, ‘Determination of Volatile Organic Compounds in Consumer Products’,” California Air 

Resources Board, Sacramento, CA, May 5. 

CARB (2008): "Air Resources Board Reactivity Programs." Web page at http://www.arb.ca.gov/ 

research/reactivity/reactivity.htm. Last updated June, 2008 

Calvert, J. G., R. Atkinson, J. A. Kerr, S. Madronich, G. K. Moortgat, T. J. Wallington and G. Yarwood 

(2003): “The Mechanisms of Atmospheric Oxidation of Alkenes,” Oxford University Press, New 

York, 

Carter, W. P. L. (1994a): “Development of Ozone Reactivity Scales for Volatile Organic Compounds,” J. 

Air & Waste Manage. Assoc., 44, 881-899. 

Carter, W. P. L. (1994b): “Calculation of Reactivity Scales Using an Updated Carbon Bond IV 

Mechanism,” Report Prepared for Systems Applications International Under Funding from the 

Auto/Oil Air Quality Improvement Research Program, April 12. 

Carter, W. P. L. (2000a): “Documentation of the SAPRC-99 Chemical Mechanism for VOC Reactivity 

Assessment,” Report to the California Air Resources Board, Contracts 92-329 and 95-308, May 

8. Available at http://cert.ucr.edu/~carter/absts.htm#saprc99 and http://www.cert.ucr.edu/~carter 

/reactdat.htm. 

Carter, W. P. L. (2000b): “Implementation of the SAPRC-99 Chemical Mechanism into the Models-3 

Framework,” Report to the United States Environmental Protection Agency, January 29. 

Available at http://www.cert.ucr.edu/~carter/absts.htm#s99mod3. 
32 

Carter, W. P. L. (2002): “Development of a Next Generation Environmental Chamber Facility for 

Chemical Mechanism and VOC Reactivity Research,” Draft Research Plan and First Progress 

Report to the United States Environmental Protection Agency Cooperative Agreement CR 

827331-01-0, January 3. Available at http://www.cert.ucr.edu/~carter/epacham. 

Carter, W. P. L. (2004): “Evaluation of a Gas-Phase Atmospheric Reaction Mechanism for Low NOx

Conditions,” Final Report to California Air Resources Board Contract No. 01-305, May 5. 

Available at http://www.cert.ucr.edu/~carter/absts.htm#lnoxrpt. 

Carter, W. P. L. (2007): "Investigation of the Atmospheric Ozone Impacts of Methyl Iodide," Final 

Report to Arysta LifeScience Corporation, Contract UCR-07041867, July 31. Available at 

http://www.cert.ucr.edu/~carter/absts.htm#ch3irep. 

Carter, W. P. L. (2008). "Estimation of the Ground-Level Atmospheric Ozone Formation Potential of 

2,3,3,3-Tetrafluoropropene," Draft Report to Honeywell International Inc – Specialty Materials, 

June 23. 

Carter, W. P. L. (2009a): "Development of the SAPRC-07 Chemical Mechanism and Updated Ozone 

Reactivity Scale," Revised final report to the California Air Resources Board Contract No. 03-

318, March 20. Available at http://www.cert.ucr.edu/~carter/SAPRC. 

Carter, W. P. L. (2009b). "Investigation of the Atmospheric Ozone Impacts of Trans 1,3,3,3-Tetrafluoropropene," Final Report to Honeywell International Inc. Contract UCR-09010016, February 

9. Available at http://www.cert.ucr.edu/~carter/absts.htm #ZEErept. 

Carter, W. P. L. and R. Atkinson (1987): “An Experimental Study of Incremental Hydrocarbon 

Reactivity,” Environ. Sci. Technol., 21, 670-679 

Carter, W. P. L. and R. Atkinson (1989): “A Computer Modeling Study of Incremental Hydrocarbon 

Reactivity”, Environ. Sci. Technol., 23, 864. 

Carter, W. P .L., and Lurmann, F. W. (1991) Evaluation of a detailed gas-phase atmospheric reaction 

mechanism using environmental chamber data. Atmos. Environ. 25A:2771-2806. 

Carter, W. P. L., J. A. Pierce, I. L. Malkina, D. Luo and W. D. Long (1993): “Environmental Chamber 

Studies of Maximum Incremental Reactivities of Volatile Organic Compounds,” Report to 

Coordinating Research Council, Project No. ME-9, California Air Resources Board Contract No. 

A032-0692; South Coast Air Quality Management District Contract No. C91323, United States 

Environmental Protection Agency Cooperative Agreement No. CR-814396-01-0, University 

Corporation for Atmospheric Research Contract No. 59166, and Dow Corning Corporation. April 

1. Available at http://www.cert.ucr.edu/~carter/absts.htm#rct1rept 

Carter, W. P. L., D. Luo, I. L. Malkina, and D. Fitz (1995a): “The University of California, Riverside 

Environmental Chamber Data Base for Evaluating Oxidant Mechanism. Indoor Chamber 

Experiments through 1993,” Report submitted to the U. S. Environmental Protection Agency, 

EPA/AREAL, Research Triangle Park, NC., March 20.. 
33 

Carter, W. P. L., D. Luo, I. L. Malkina, and J. A. Pierce (1995b): “Environmental Chamber Studies of 

Atmospheric Reactivities of Volatile Organic Compounds. Effects of Varying ROG Surrogate 

and NOx,” Final report to Coordinating Research Council, Inc., Project ME-9, California Air 

Resources Board, Contract A032-0692, and South Coast Air Quality Management District, 

Contract C91323. March 24. Available at http://www.cert.ucr.edu/~carter/absts.htm#rct2rept. 

Carter, W. P. L., J. H. Seinfeld, D. R. Fitz and G. S. Tonnesen (1999): “Development of a NextGeneration Environmental Chamber Facility for Chemical Mechanism and VOC Reactivity 

Evaluation,” Research Proposal to the United States Environmental Protection Agency, February 

22. (Available at http://www.cert.ucr.edu/~carter/epacham/proposal.htm.) 

Carter, W. P. L. and I. L. Malkina (2005): “Evaluation of Atmospheric Impacts of Selected Coatings 

VOC Emissions,” Final report to the California Air Resources Board Contract No. 00-333, March 

15. Available at http://www.cert.ucr.edu/~carter/absts.htm#coatrpt. 

Carter, W. P. L., D. R. Cocker III, D. R. Fitz, I. L. Malkina, K. Bumiller, C. G. Sauer, J. T. Pisano, C. 

Bufalino, and C. Song (2005a): “A New Environmental Chamber for Evaluation of Gas-Phase 

Chemical Mechanisms and Secondary Aerosol Formation”, Atmos. Environ. 39 7768-7788. 

Carter, W. P. L., I. L. Malkina, D. R. Cocker III, and C. Song (2005b): “Environmental Chamber Studies 

of VOC Species in Architectural Coatings and Mobile Source Emissions,” Final Report to the 

South Coast Air Quality Management District Contract No. 03468, July 5. Available at 

http://www.cert.ucr.edu/~carter/absts.htm#scaqcham. 

Carter, W. P. L. and I. L. Malkina (2007): “Investigation of the Atmospheric Impacts of Selected 

Pesticides,” Final Report to the California Air Resources Board Contract 04-334, January 10. 

Available at http://www.cert.ucr.edu/~carter/absts.htm#pestrep. 

Cocker, D. R., R. C. Flagan, and J. H. Seinfeld. (2001). “State-of-the-Art Chamber Facility for Studying 

Atmospheric Aerosol Chemistry,” Environ. Sci. Technol. 35, 2594-2601. 

Collins D. R., R. C. Flagan, and J. H. Seinfeld (2002). "Improved inversion of scanning DMA data," 

Aerosol Science Technology, 36, 2-9. 

Dimitriades, B. (1999): “Scientific Basis of an Improved EPA Policy on Control of Organic Emissions for 

Ambient Ozone Reduction,” J. Air & Waste Manage. Assoc. 49, 831-838 

EPA (2005): “Interim Guidance on Control of Volatile Organic Compounds in Ozone State 

Implementation Plans,” Federal Register, 70, 54046-54051, September 13. 

Hurley, M.D., T.J. Wallington, M.S. Javadi, and O.J. Nielsen (2008): "Atmospheric chemistry of 

CF3CF=CH2: Products and mechanisms of Cl atom and OH radical initiated oxidation," Chemical 

Physics Letters 450, 263-267 

IUPAC (2004a): IUPAC Subcommittee on Gas Kinetic Data Evaluation – Data Sheet PF1 Website: 

http://www.iupac-kinetic.ch.cam.ac.uk/. July 23. 

IUPAC (2004b): IUPAC Subcommittee on Gas Kinetic Data Evaluation – Data Sheet PF3 Website: 

http://www.iupac-kinetic.ch.cam.ac.uk/. July 23. 
34 

IUPAC (2005): IUPAC Subcommittee on Gas Kinetic Data Evaluation – Data Sheet oFOx30 Website: 

http://www.iupac-kinetic.ch.cam.ac.uk/. March 29. 

IUPAC (2006): "Evaluated Kinetic and Photochemical Data". IUPAC Subcommittee on Gas Kinetic Data 

Evaluation for Atmospheric Chemistry. Web Version. Available at http://www.iupackinetic.ch.cam.ac.uk. Latest data sheets dated June, 2006. 

Johnson, G. M. (1983): “Factors Affecting Oxidant Formation in Sydney Air,” in “The Urban 

Atmosphere -- Sydney, a Case Study.” Eds. J. N. Carras and G. M. Johnson (CSIRO, 

Melbourne), pp. 393-408. 

Nielsen, O.J., M.S. Javadi, M.P. Sulbaek Andersen, M.D. Hurley, T.J. Wallington, and R. Singh (2007): 

"Atmospheric chemistry of CF3CF=CH2: Kinetics and mechanisms of gas-phase reactions with Cl 

atoms, OH radicals, and O3," Chem. Phys. Lett. 439, 18-22 

Orlando, J. J. and G. S. Tyndall (2003): "Gas phase UV absorption spectra for peracetic acid, and for 

acetic acid monomers and dimers," J. Photochem. Photobiol A, 157, 161-166. 

RRWG (1999a): “VOC Reactivity Policy White Paper,” Prepared by the Reactivity Research Work 

Group Policy Team, October 1. Available at http://www.narsto.org/section.src?SID=10. 

Sellevåg, S. R.; Kelly, T.; Sidebottom, H.; Nielsen, C. J. (2004): “A study of the IR and UV-Vis 

absorption cross-sections, photolysis and OH-initiated oxidation of CF3CHO and CF3CH2CHO,” 

Phys. Chem. Chem. Phys. 6, 1243-1252. 

Wallington, T. J. and Hurley, M. D. (1993): “Atmospheric chemistry of formyl fluoride: reaction with 

hydroxyl radicals,” Environ. Sci. Technol., 27, 1448–1452. 

Zafonte, L., P. L. Rieger, and J. R. Holmes (1977): “Nitrogen Dioxide Photolysis in the Los Angeles 

Atmosphere,” Environ. Sci. Technol. 11, 483-487. 
35 

APPENDIX A. BASE MECHANISM LISTING 

Table A-1. List of model species used in the base SAPRC-07 mechanism, including the VOC species 

used in the chamber and atmospheric reactivity simulations. The model species used for 

2,3,3,3-tetrafluoropropene and its reaction products and intermediates are given in Table 

2, above. 

Name Description 

 

Constant Species.

 O2 Oxygen 

 M Air 

 H2O Water 

 H2 Hydrogen Molecules 

 HV Light 

Active Inorganic Species.

 O3 Ozone 

 NO Nitric Oxide 

 NO2 Nitrogen Dioxide 

 NO3 Nitrate Radical 

 N2O5 Nitrogen Pentoxide 

 HONO Nitrous Acid 

 HNO3 Nitric Acid 

 HNO4 Peroxynitric Acid 

 HO2H Hydrogen Peroxide 

 CO Carbon Monoxide 

 SO2 Sulfur Dioxide 

 H2 Hydrogen 

Active Radical Species and Operators.

 OH Hydroxyl Radicals 

 HO2 Hydroperoxide Radicals 

 MEO2 Methyl Peroxy Radicals 

RO2C Peroxy Radical Operator representing NO to NO2 and NO3 to NO2 conversions, and the 

effects of peroxy radical reactions on acyl peroxy and other peroxy radicals. 

RO2XC Peroxy Radical Operator representing NO consumption (used in conjunction with organic 

nitrate formation), and the effects of peroxy radical reactions on NO3, acyl peroxy radicals, 

and other peroxy radicals. 

 MECO3 Acetyl Peroxy Radicals 

 RCO3 Peroxy Propionyl and higher peroxy acyl Radicals 

 BZCO3 Peroxyacyl radical formed from Aromatic Aldehydes 

 MACO3 Peroxyacyl radicals formed from methacrolein and other acroleins. 

Steady State Radical Species

 O3P Ground State Oxygen Atoms 

 O1D Excited Oxygen Atoms 

 TBUO t-Butoxy Radicals 

 BZO Phenoxy Radicals 
Table A-1 (continued) 

36 

Name Description 

 

PAN and PAN Analogues

 PAN Peroxy Acetyl Nitrate 

 PAN2 PPN and other higher alkyl PAN analogues 

 PBZN PAN analogues formed from Aromatic Aldehydes 

 MAPAN PAN analogue formed from Methacrolein 

Explicit and Lumped Molecule Reactive Organic Product Species

 HCHO Formaldehyde 

 CCHO Acetaldehyde 

 RCHO Lumped C3+ Aldehydes. Mechanism based on propionaldehyde 

 ACET Acetone 

MEK Ketones and other non-aldehyde oxygenated products that react with OH radicals faster 

than 5 x 10-13 but slower than 5 x 10-12 cm3

 molec-2 sec-1. Mechanism based on methyl ethyl 

ketone. 

 MEOH Methanol 

 HCOOH Formic Acid 

 CCOOH Acetic Acid. Also used for peroxyacetic acid. 

 RCOOH Higher organic acids and peroxy acids. Mechanism based on propionic acid. 

 COOH Methyl Hydroperoxide 

ROOH Lumped organic hydroperoxides with 2-4 carbons. Mechanism based n-propyl 

hydroperoxide. 

R6OOH Lumped organic hydroperoxides with 5 or more carbons (other than those formed following 

OH addition to aromatic rings, which are represented separately). Mechanism based on 3-

hexyl hydroperoxide. 

RAOOH Organic hydroperoxides formed following OH addition to aromatic rings, which is 

represented separately because of their probable role in SOA formation. Mechanism based 

on two isomers expected to be formed in the m-xylene system. 

 GLY Glyoxal 

 MGLY Methyl Glyoxal 

 BACL Biacetyl 

 CRES Phenols and Cresols. Mechanism based on o-cresol. 

 NPHE Nitrophenols 

 BALD Aromatic aldehydes. Mechanism based on benzaldehyde 

 MACR Methacrolein 

 MVK Methyl Vinyl Ketone 

 IPRD Lumped isoprene product species. Mechanism based on that of Carter and Atkinson (1996).

Aromatic unsaturated ring fragmentation products (see discussion of aromatic mechanisms) 

AFG1 Lumped photoreactive monounsaturated dicarbonyl aromatic fragmentation products that 

photolyze to form radicals. 

AFG2 Lumped photoreactive monounsaturated dicarbonyl aromatic fragmentation products that 

photolyze to form non-radical products 

 AFG3 Lumped diunsaturatred dicarbonyl aromatic fragmentation product. 
Table A-1 (continued) 

37 

Name Description 

 

Lumped Parameter Products

PROD2 Ketones and other non-aldehyde oxygenated products that react with OH radicals faster 

than 5 x 10-12 cm3

 molec-2 sec-1. Mechanism based on CH3C(O)CH2CH2CH2OH, CH3C(O)-

CH2CH(CH3)CH2OH, CH3CH2C(O)CH2CH2CH(CH3)OH, CH3CH2C(O)CH2CH2CH(OH)-

CH2CH3, and CH3CH2CH2CH(OH)CH2-CH2C(O)CH2CH3 (PROD2-1 through 5), each 

weighed equally. 

RNO3 Lumped Organic Nitrates. Mechanism based on CH3CH2CH(CH3)ONO2, CH3CH(OH)CH2-

CH2CH2ONO2, CH3CH2CH(CH3)CH(CH3)ONO2, CH3CH2CH2CH2CH2CH(ONO2)CH2OH, 

CH3CH2C(CH3)(ONO2)CH2CH(CH3)CH3, and CH3CH2CH2CH2CH2CH2CH2CH(ONO2)-

CH2CH3 (RNO3-1 through 6), each weighed equally. 

Steady state operators used to represent radical or product formation in peroxy radical reactions.

xHO2 Formation of HO2 from alkoxy radicals formed in peroxy radical reactions with NO and 

NO3 (100% yields) and RO2 (50% yields) 

 xOH As above, but for OH 

 xNO2 As above, but for NO2

 xMEO2 As above, but for MEO2 

 xMECO3 As above, but for MECO3 

 xRCO3 As above, but for RCO3 

 xMACO3 As above, but for MACO3 

 xTBUO As above, but for TBUO 

 xCO As above, but for CO 

 xHNO3 As above, but for HNO3 

 xHCHO As above, but for HCHO 

 xCCHO As above, but for CCHO 

 xRCHO As above, but for RCHO 

 xACET As above, but for ACET 

 xMEK As above, but for MEK 

 xPROD2 As above, but for PROD2 

 xGLY As above, but for GLY 

 xMGLY As above, but for MGLY 

 xBACL As above, but for BACL 

 xBALD As above, but for BALD 

 xAFG1 As above, but for AFG1 

 xAFG2 As above, but for AFG2 

 xAFG3 As above, but for AFG3 

 xMACR As above, but for MACR 

 xMVK As above, but for MVK 

 xIPRD As above, but for IPRD 

 xRNO3 As above, but for RNO3 

 xHCOOH As above, but for HCOOH 

 xCCOOH As above, but for CCOOH 

 xRCOOH As above, but for RCOOH 

zRNO3 Formation of RNO3 in the RO2 + NO, reaction, or formation of corresponding non-nitrate 

products (represented by PROD2) formed from alkoxy radicals formed in RO2 + NO3 and 

(in 50% yields) RO2 + RO2 reactions. 
Table A-1 (continued) 

38 

Name Description 

 

yROOH Formation of ROOH following RO2 + HO2 reactions, or formation of H-shift 

disproportionation products (represented by MEK) in the RO2 + RCO3 and (in 50% yields) 

RO2 + RO2 reactions. 

yR6OOH As above, but with the RO2 + HO2 product represented by R6OOH and the H-shift products 

are represented by PROD2. 

 yRAOOH As above, but with the RO2 + HO2 product represented by R6OOH 

Non-Reacting Species

 CO2 Carbon Dioxide 

 SULF Sulfates (SO3 or H2SO4) 

 XC Lost Carbon or carbon in unreactive products 

 XN Lost Nitrogen or nitrogen in unreactive products 

Primary Organics Represented explicitly

 CH4 Methane 

 ETHENE Ethene 

 ISOPRENE Isoprene 

 ACETYLEN Acetylene 

 BENZENE Benzene 

 ETHANE Ethane (not part of the base mechanism, but used in atmospheric reactivity simulations) 

Organics represented explicitly in the chamber simulations (not used in the atmospheric simulations)

 N-C4 n-Butane 

 N-C6 n-Hexane 

 N-C8 n-Octane 

 PROPENE Propene 

 T-2-BUTE trans-2-Butene 

 TOLUENE Toluene 

 M-XYLENE m-Xylene 

Lumped model species used in the atmospheric reactivity simulations (not used in chamber simulations) 

ALK1 Alkanes and other non-aromatic compounds that react only with OH, and have kOH (OH 

radical rate constant) between 2 and 5 x 102

 ppm-1 min-1. (Primarily ethane) 

ALK2 Alkanes and other non-aromatic compounds that react only with OH, and have kOH 

between 5 x 102

 and 2.5 x 103 ppm-1 min-1. (Primarily propane) 

ALK3 Alkanes and other non-aromatic compounds that react only with OH, and have kOH 

between 2.5 x 103

 and 5 x 103 ppm-1 min-1. 

ALK4 Alkanes and other non-aromatic compounds that react only with OH, and have kOH 

between 5 x 103

 and 1 x 104 ppm-1 min-1. 

ALK5 Alkanes and other non-aromatic compounds that react only with OH, and have kOH greater 

than 1 x 104

 ppm-1 min-1. 

 ARO1 Aromatics with kOH < 2x104

 ppm-1 min-1. 

 ARO2 Aromatics with kOH > 2x104

 ppm-1 min-1. 

 OLE1 Alkenes (other than ethene) with kOH < 7x104

 ppm-1 min-1. 

 OLE2 Alkenes with kOH > 7x104

 ppm-1 min-1. 

 TERP Terpenes 
39 

Table A-2. Reactions and rate constants in the SAPRC-07 mechanism used in this work. See Carter 

(2009a) for documentation. The reactions used for 2,3,3,3-tetrafluoropropene are given in 

Table 3, above. 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

Inorganic Reactions 

 1 NO2 + HV = NO + O3P Phot Set= NO2-06 

 2 O3P + O2 + M = O3 + M 5.68e-34 5.68e-34 0.00 -2.60

 3 O3P + O3 = #2 O2 8.34e-15 8.00e-12 4.09 

 4 O3P + NO = NO2 1.64e-12 Falloff, F=0.60, N=1.00

 0: 9.00e-32 0.00 -1.50

 inf: 3.00e-11 0.00 0.00

 5 O3P + NO2 = NO + O2 1.03e-11 5.50e-12 -0.37 

 6 O3P + NO2 = NO3 3.24e-12 Falloff, F=0.60, N=1.00

 0: 2.50e-31 0.00 -1.80

 inf: 2.20e-11 0.00 -0.70

 7 O3 + NO = NO2 + O2 2.02e-14 3.00e-12 2.98 

 8 O3 + NO2 = O2 + NO3 3.72e-17 1.40e-13 4.91 

 9 NO + NO3 = #2 NO2 2.60e-11 1.80e-11 -0.22 

 10 NO + NO + O2 = #2 NO2 1.93e-38 3.30e-39 -1.05 

 11 NO2 + NO3 = N2O5 1.24e-12 Falloff, F=0.35, N=1.33

 0: 3.60e-30 0.00 -4.10

 inf: 1.90e-12 0.00 0.20

 12 N2O5 = NO2 + NO3 5.69e-2 Falloff, F=0.35, N=1.33

 0: 1.30e-3 21.86 -3.50

 inf: 9.70e+14 22.02 0.10

 13 N2O5 + H2O = #2 HNO3 2.50e-22 

 14 N2O5 + H2O + H2O = #2 HNO3 + H2O 1.80e-39 

 N2O5 + HV = NO3 + NO + O3P (Slow) 

 N2O5 + HV = NO3 + NO2 (Slow) 

 15 NO2 + NO3 = NO + NO2 + O2 6.75e-16 4.50e-14 2.50 

 16 NO3 + HV = NO + O2 Phot Set= NO3NO-06 

 17 NO3 + HV = NO2 + O3P Phot Set= NO3NO2-6 

 18 O3 + HV = O1D + O2 Phot Set= O3O1D-06 

 19 O3 + HV = O3P + O2 Phot Set= O3O3P-06 

 20 O1D + H2O = #2 OH 1.99e-10 

 21 O1D + M = O3P + M 3.28e-11 2.38e-11 -0.19 

 22 OH + NO = HONO 7.31e-12 Falloff, F=0.60, N=1.00

 0: 7.00e-31 0.00 -2.60

 inf: 3.60e-11 0.00 -0.10

 23 HONO + HV = OH + NO Phot Set= HONO-06 

 24 OH + HONO = H2O + NO2 5.95e-12 2.50e-12 -0.52 

 25 OH + NO2 = HNO3 1.05e-11 Falloff, F=0.60, N=1.00

 0: 1.80e-30 0.00 -3.00

 inf: 2.80e-11 0.00 0.00

 26 OH + NO3 = HO2 + NO2 2.00e-11 
Table A-2 (continued) 

40 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

27 OH + HNO3 = H2O + NO3 1.51e-13 k = 

k0+k3M/(1+k3M/k2) 

 k0: 2.40e-14 -0.91 0.00

 k2: 2.70e-17 -4.37 0.00

 k3: 6.50e-34 -2.65 0.00

 28 HNO3 + HV = OH + NO2 Phot Set= HNO3 

 29 OH + CO = HO2 + CO2 2.28e-13 k = k1 + k2 [M] 

 k1: 1.44e-13 0.00 0.00

 k2: 3.43e-33 0.00 0.00

 30 OH + O3 = HO2 + O2 7.41e-14 1.70e-12 1.87 

 31 HO2 + NO = OH + NO2 8.85e-12 3.60e-12 -0.54 

 32 HO2 + NO2 = HNO4 1.12e-12 Falloff, F=0.60, N=1.00

 0: 2.00e-31 0.00 -3.40

 inf: 2.90e-12 0.00 -1.10

 33 HNO4 = HO2 + NO2 1.07e-1 Falloff, F=0.60, N=1.00

 0: 3.72e-5 21.16 -2.40

 inf: 5.42e+15 22.20 -2.30

 34 HNO4 + HV = #.61 {HO2 + NO2} + #.39 {OH + NO3} Phot Set= HNO4-06 

 35 HNO4 + OH = H2O + NO2 + O2 4.61e-12 1.30e-12 -0.76 

 36 HO2 + O3 = OH + #2 O2 2.05e-15 2.03e-16 -1.38 4.57

 37 HO2 + HO2 = HO2H + O2 2.84e-12 k = k1 + k2 [M] 

 k1: 2.20e-13 -1.19 0.00

 k2: 1.90e-33 -1.95 0.00

 38 HO2 + HO2 + H2O = HO2H + O2 + H2O 6.09e-30 k = k1 + k2 [M] 

 k1: 3.08e-34 -5.56 0.00

 k2: 2.66e-54 -6.32 0.00

39 NO3 + HO2 = #.8 {OH + NO2 + O2} + #.2 {HNO3 + 

O2} 

4.00e-12 

 40 NO3 + NO3 = #2 NO2 + O2 2.41e-16 8.50e-13 4.87 

 41 HO2H + HV = #2 OH Phot Set= H2O2 

 42 HO2H + OH = HO2 + H2O 1.80e-12 1.80e-12 0.00 

 43 OH + HO2 = H2O + O2 1.10e-10 4.80e-11 -0.50 

 44 OH + SO2 = HO2 + SULF 9.49e-13 Falloff, F=0.60, N=1.00

 0: 3.30e-31 0.00 -4.30

 inf: 1.60e-12 0.00 0.00

 45 OH + H2 = HO2 + H2O 7.02e-15 7.70e-12 4.17 

Methyl peroxy and methoxy reactions 

 BR01 MEO2 + NO = NO2 + HCHO + HO2 7.64e-12 2.30e-12 -0.72 

 BR02 MEO2 + HO2 = COOH + O2 4.65e-12 3.46e-13 -1.55 0.36

 BR03 MEO2 + HO2 = HCHO + O2 + H2O 4.50e-13 3.34e-14 -1.55 -3.53

 BR04 MEO2 + NO3 = HCHO + HO2 + NO2 1.30e-12 

 BR05 MEO2 + MEO2 = MEOH + HCHO + O2 2.16e-13 6.39e-14 -0.73 -1.80

 BR06 MEO2 + MEO2 = #2 {HCHO + HO2} 1.31e-13 7.40e-13 1.03 

Active Peroxy Radical Operators 

 BR07 RO2C + NO = NO2 9.23e-12 2.60e-12 -0.76 

 BR08 RO2C + HO2 = HO2 7.63e-12 3.80e-13 -1.79 
Table A-2 (continued) 

41 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

 BR09 RO2C + NO3 = NO2 2.30e-12 

BR10 RO2C + MEO2 = #.5 {RO2C + xHO2 + xHCHO + O2} 

+ #.25 {HCHO + MEOH} 

2.00e-13 

 BR11 RO2C + RO2C = 3.50e-14 

 

 BR12 RO2XC + NO = XN Same k as rxn BR07 

 BR13 RO2XC + HO2 = HO2 Same k as rxn BR08 

 BR14 RO2XC + NO3 = NO2 Same k as rxn BR09 

BR15 RO2XC + MEO2 = #.5 {RO2C + xHO2 + xHCHO + 

O2} + #.25 {HCHO + MEOH} 

Same k as rxn BR10 

 BR16 RO2XC + RO2C = Same k as rxn BR11 

 BR17 RO2XC + RO2XC = Same k as rxn BR11 

Reactions of Acyl Peroxy Radicals, PAN, and PAN analogues 

 BR18 MECO3 + NO2 = PAN 9.37e-12 Falloff, F=0.30, N=1.41

 0: 2.70e-28 0.00 -7.10

 inf: 1.21e-11 0.00 -0.90

 BR19 PAN = MECO3 + NO2 6.27e-4 Falloff, F=0.30, N=1.41

 0: 4.90e-3 24.05 0.00

 inf: 4.00e+16 27.03 0.00

BR20 PAN + HV = #.6 {MECO3 + NO2} + #.4 {MEO2 + 

CO2 + NO3} 

Phot Set= PAN 

 BR21 MECO3 + NO = MEO2 + CO2 + NO2 1.97e-11 7.50e-12 -0.58 

 BR22 MECO3 + HO2 = CCOOH + #.7 O2 + #.3 O3 1.36e-11 5.20e-13 -1.95 

 BR23 MECO3 + NO3 = MEO2 + CO2 + NO2 + O2 Same k as rxn BR09 

BR24 MECO3 + MEO2 = #.9 {CCOOH + HCHO + O2} + #.1 

{HCHO + HO2 + MEO2 + CO2} 

1.06e-11 2.00e-12 -0.99 

 BR25 MECO3 + RO2C = CCOOH 1.56e-11 4.40e-13 -2.13 

 BR26 MECO3 + RO2XC = CCOOH Same k as rxn BR25 

 BR27 MECO3 + MECO3 = #2 {MEO2 + CO2} + O2 1.54e-11 2.90e-12 -0.99 

 

 BR28 RCO3 + NO2 = PAN2 1.21e-11 1.21e-11 0.00 -1.07

 BR29 PAN2 = RCO3 + NO2 5.48e-4 8.30e+16 27.70 

BR30 RCO3 + NO = NO2 + RO2C + xHO2 + yROOH + 

xCCHO + CO2 

2.08e-11 6.70e-12 -0.68 

 BR31 RCO3 + HO2 = RCOOH + #.75 O2 + #.25 O3 Same k as rxn BR22 

BR32 RCO3 + NO3 = NO2 + RO2C + xHO2 + yROOH + 

xCCHO + CO2 + O2 

Same k as rxn BR09 

 BR33 RCO3 + MEO2 = RCOOH + HCHO + O2 Same k as rxn BR24 

 BR34 RCO3 + RO2C = RCOOH + O2 Same k as rxn BR25 

 BR35 RCO3 + RO2XC = RCOOH + O2 Same k as rxn BR25 

BR36 RCO3 + MECO3 = #2 CO2 + MEO2 + RO2C + xHO2 

+ yROOH + xCCHO + O2 

Same k as rxn BR27 

BR37 RCO3 + RCO3 = #2 {RO2C + xHO2 + xCCHO + 

yROOH + CO2} 

Same k as rxn BR27 

 

 BR38 BZCO3 + NO2 = PBZN 1.37e-11 

 BR39 PBZN = BZCO3 + NO2 4.27e-4 7.90e+16 27.82 

 BR40 BZCO3 + NO = NO2 + CO2 + BZO + RO2C Same k as rxn BR30 
Table A-2 (continued) 

42 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

BR41 BZCO3 + HO2 = RCOOH + #.75 O2 + #.25 O3 + #4 

XC 

Same k as rxn BR22 

 BR42 BZCO3 + NO3 = NO2 + CO2 + BZO + RO2C + O2 Same k as rxn BR09 

 BR43 BZCO3 + MEO2 = RCOOH + HCHO + O2 + #4 XC Same k as rxn BR24 

 BR44 BZCO3 + RO2C = RCOOH + O2 + #4 XC Same k as rxn BR25 

 BR45 BZCO3 + RO2XC = RCOOH + O2 + #4 XC Same k as rxn BR25 

 BR46 BZCO3 + MECO3 = #2 CO2 + MEO2 + BZO + RO2C Same k as rxn BR27 

BR47 BZCO3 + RCO3 = #2 CO2 + RO2C + xHO2 + yROOH 

+ xCCHO + BZO + RO2C 

Same k as rxn BR27 

 BR48 BZCO3 + BZCO3 = #2 {BZO + RO2C + CO2} Same k as rxn BR27 

 BR49 MACO3 + NO2 = MAPAN Same k as rxn BR28 

 BR50 MAPAN = MACO3 + NO2 4.79e-4 1.60e+16 26.80 

 BR51 MACO3 + NO = NO2 + CO2 + HCHO + MECO3 Same k as rxn BR30 

 BR52 MACO3 + HO2 = RCOOH + #.75 O2 + #.25 O3 + XC Same k as rxn BR22 

BR53 MACO3 + NO3 = NO2 + CO2 + HCHO + MECO3 + 

O2 

Same k as rxn BR09 

 BR54 MACO3 + MEO2 = RCOOH + HCHO + XC + O2 Same k as rxn BR24 

 BR55 MACO3 + RO2C = RCOOH + XC Same k as rxn BR25 

 BR56 MACO3 + RO2XC = RCOOH + O2 + XC Same k as rxn BR25 

BR57 MACO3 + MECO3 = #2 CO2 + MEO2 + HCHO + 

MECO3 + O2 

Same k as rxn BR27 

BR58 MACO3 + RCO3 = HCHO + MECO3 + RO2C + xHO2 

+ yROOH + xCCHO + #2 CO2 

Same k as rxn BR27 

BR59 MACO3 + BZCO3 = HCHO + MECO3 + BZO + 

RO2C + #2 CO2 

Same k as rxn BR27 

 BR60 MACO3 + MACO3 = #2 {HCHO + MECO3 + CO2} Same k as rxn BR27 

Other Organic Radical Species 

 BR61 TBUO + NO2 = RNO3 + #-2 XC 2.40e-11 

 BR62 TBUO = ACET + MEO2 1.18e+3 7.50e+14 16.20 

 

 BR63 BZO + NO2 = NPHE 3.79e-11 2.30e-11 -0.30 

 BR64 BZO + HO2 = CRES + #-1 XC Same k as rxn BR08 

 BR65 BZO = CRES + RO2C + xHO2 + #-1 XC 1.00e-3 

Steady-State Peroxy Radical operators (for formation of inorganic and radical products) [c]

 RO01 xHO2 = HO2 k is variable parameter: RO2RO 

 RO02 xHO2 = k is variable parameter: RO2XRO 

 RO03 xOH = OH k is variable parameter: RO2RO 

 RO04 xOH = k is variable parameter: RO2XRO 

 RO05 xNO2 = NO2 k is variable parameter: RO2RO 

 RO06 xNO2 = XN k is variable parameter: RO2XRO 

 RO07 xMEO2 = MEO2 k is variable parameter: RO2RO 

 RO08 xMEO2 = XC k is variable parameter: RO2XRO 

 RO09 xMECO3 = MECO3 k is variable parameter: RO2RO 

 RO10 xMECO3 = #2 XC k is variable parameter: RO2XRO 

 RO11 xRCO3 = RCO3 k is variable parameter: RO2RO 

 RO12 xRCO3 = #3 XC k is variable parameter: RO2XRO 

 RO13 xMACO3 = MACO3 k is variable parameter: RO2RO 
Table A-2 (continued) 

43 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

 RO14 xMACO3 = #4 XC k is variable parameter: RO2XRO 

 RO15 xTBUO = TBUO k is variable parameter: RO2RO 

 RO16 xTBUO = #4 XC k is variable parameter: RO2XRO 

 RO17 xCO = CO k is variable parameter: RO2RO 

 RO18 xCO = XC k is variable parameter: RO2XRO 

 RO19 xHNO3 = HNO3 k is variable parameter: RO2RO 

 RO20 xHNO3 = XN k is variable parameter: RO2XRO 

Explicit and Lumped Molecule Organic Products 

 BP01 HCHO + HV = #2 HO2 + CO Phot Set= HCHOR-06 

 BP02 HCHO + HV = H2 + CO Phot Set= HCHOM-06 

 BP03 HCHO + OH = HO2 + CO + H2O 8.47e-12 5.40e-12 -0.27 

 BP07 HCHO + NO3 = HNO3 + HO2 + CO 6.06e-16 2.00e-12 4.83 

 

 BP08 CCHO + OH = MECO3 + H2O 1.49e-11 4.40e-12 -0.73 

 BP09 CCHO + HV = CO + HO2 + MEO2 Phot Set= CCHO_R 

 BP10 CCHO + NO3 = HNO3 + MECO3 2.84e-15 1.40e-12 3.70 

 

BP11 RCHO + OH = #.965 RCO3 + #.035 {RO2C + xHO2 + 

xCO + xCCHO + yROOH} 

1.97e-11 5.10e-12 -0.80 

BP12 RCHO + HV = RO2C + xHO2 + yROOH + xCCHO + 

CO + HO2 

Phot Set= C2CHO 

 BP13 RCHO + NO3 = HNO3 + RCO3 6.74e-15 1.40e-12 3.18 

 

 BP14 ACET + OH = RO2C + xMECO3 + xHCHO + yROOH 1.91e-13 4.56e-14 -0.85 3.65

 BP15 ACET + HV = #.62 MECO3 + #1.38 MEO2 + #.38 CO Phot Set= ACET-06, qy= 0.5 

 

BP16 MEK + OH = #.967 RO2C + #.039 {RO2XC + 

zRNO3} + #.376 xHO2 + #.51 xMECO3 + #.074 

xRCO3 + #.088 xHCHO + #.504 xCCHO + #.376 

xRCHO + yROOH + #.3 XC 

1.20e-12 1.30e-12 0.05 2.00

BP17 MEK + HV = MECO3 + RO2C + xHO2 + xCCHO + 

yROOH 

Phot Set= MEK-06, qy= 0.175 

 

 BP18 MEOH + OH = HCHO + HO2 9.02e-13 2.85e-12 0.69 

 BP19 HCOOH + OH = HO2 + CO2 4.50e-13 

BP20 CCOOH + OH = #.509 MEO2 + #.491 RO2C + #.509 

CO2 + #.491 xHO2 + #.491 xMGLY + #.491 yROOH + 

#-0.491 XC 

7.26e-13 4.20e-14 -1.70 

BP21 RCOOH + OH = RO2C + #.08 CO2 + xHO2 + #.063 

CO2 + #.142 xCCHO + #.4 xRCHO + #.457 xBACL + 

yROOH + #-0.455 XC 

1.20e-12 

 

 BP22 COOH + OH = H2O + #.3 {HCHO + OH} + #.7 MEO2 7.40e-12 3.80e-12 -0.40 

 BP23 COOH + HV = HCHO + HO2 + OH Phot Set= COOH 

 

BP24 ROOH + OH = #.744 OH + #.251 RO2C + #.004 

RO2XC + #.004 zRNO3 + #.744 RCHO + #.239 xHO2 

+ #.012 xOH + #.012 xHCHO + #.012 xCCHO + #.205 

xRCHO + #.034 xPROD2 + #.256 yROOH + #-0.115 

XC 

2.50e-11 

 BP25 ROOH + HV = RCHO + HO2 + OH Phot Set= COOH 

 
Table A-2 (continued) 

44 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

BP26 R6OOH + OH = #.84 OH + #.222 RO2C + #.029 

RO2XC + #.029 zRNO3 + #.84 PROD2 + #.09 xHO2 + 

#.041 xOH + #.02 xCCHO + #.075 xRCHO + #.084 

xPROD2 + #.16 yROOH + #.02 XC 

5.60e-11 

BP27 R6OOH + HV = OH + #.142 HO2 + #.782 RO2C + 

#.077 RO2XC + #.077 zRNO3 + #.085 RCHO + #.142 

PROD2 + #.782 xHO2 + #.026 xCCHO + #.058 

xRCHO + #.698 xPROD2 + #.858 yR6OOH + #.017 

XC 

Phot Set= COOH 

 

BP28 RAOOH + OH = #.139 OH + #.148 HO2 + #.589 RO2C 

+ #.124 RO2XC + #.124 zRNO3 + #.074 PROD2 + 

#.147 MGLY + #.139 IPRD + #.565 xHO2 + #.024 

xOH + #.448 xRCHO + #.026 xGLY + #.030 xMEK + 

#.252 xMGLY + #.073 xAFG1 + #.073 xAFG2 + #.713 

yR6OOH + #2.674 XC 

1.41e-10 

BP29 RAOOH + HV = OH + HO2 + #.5 {GLY + MGLY + 

AFG1 + AFG2} + #.5 XC 

Phot Set= COOH 

 

 BP30 GLY + HV = #2 {CO + HO2} Phot Set= GLY-07R 

 BP31 GLY + HV = HCHO + CO Phot Set= GLY-07M 

BP32 GLY + OH = #.63 HO2 + #1.26 CO + #.37 RCO3 + #-

.37 XC 

1.10e-11 

BP33 GLY + NO3 = HNO3 + #.63 HO2 + #1.26 CO + #.37 

RCO3 + #-.37 XC 

1.02e-15 2.80e-12 4.72 

 

 BP34 MGLY + HV = HO2 + CO + MECO3 Phot Set= MGLY-06 

 BP35 MGLY + OH = CO + MECO3 1.50e-11 

 BP36 MGLY + NO3 = HNO3 + CO + MECO3 2.53e-15 1.40e-12 3.77 

 

 BP37 BACL + HV = #2 MECO3 Phot Set= BACL-07 

 

BP38 CRES + OH = #.2 BZO + #.8 {RO2C + xHO2 + 

yR6OOH} + #.25 xMGLY + #5.05 XC 

4.03e-11 1.70e-12 -1.89 

 BP39 CRES + NO3 = HNO3 + BZO + XC 1.40e-11 

 

 BP40 NPHE + OH = BZO + XN 3.50e-12 

 BP41 NPHE + HV = HONO + #6 XC Phot Set= NO2-06, qy= 1.5e-3 

 BP42 NPHE + HV = #6 XC + XN Phot Set= NO2-06, qy= 1.5e-2 

 

 BP43 BALD + OH = BZCO3 1.20e-11 

 BP44 BALD + HV = #7 XC Phot Set= BALD-06, qy= 0.06 

 BP45 BALD + NO3 = HNO3 + BZCO3 2.73e-15 1.34e-12 3.70 

 
Table A-2 (continued) 

45 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

Lumped Unsaturated Aromatic Ring-Opening Products 

BP46 AFG1 + OH = #.217 MACO3 + #.723 RO2C + #.060 

{RO2XC + zRNO3} + #.060 zRNO3 + #.521 xHO2 + 

#.201 xMECO3 + #.334 xCO + #.407 xRCHO + #.129 

xMEK + #.107 xGLY + #.267 xMGLY + #.783 

yR6OOH + #-.076 XC 

7.40e-11 

BP47 AFG1 + O3 = #.826 OH + #.522 HO2 + #.652 RO2C + 

#.522 CO + #.174 CO2 + #.432 GLY + #.568 MGLY + 

#.652 xRCO3 + #.652 xHCHO + #.652 yR6OOH + #-

.872 XC 

9.66e-18 

BP48 AFG1 + HV = #1.023 HO2 + #.173 MEO2 + #.305 

MECO3 + #.500 MACO3 + #.695 CO + #.195 GLY + 

#.305 MGLY + #.217 XC 

Phot Set= AFG1 

 

BP49 AFG2 + OH = #.217 MACO3 + #.723 RO2C + #.060 

{RO2XC + zRNO3} + #.060 zRNO3 + #.521 xHO2 + 

#.201 xMECO3 + #.334 xCO + #.407 xRCHO + #.129 

xMEK + #.107 xGLY + #.267 xMGLY + #.783 

yR6OOH + #-.076 XC 

7.40e-11 

BP50 AFG2 + O3 = #.826 OH + #.522 HO2 + #.652 RO2C + 

#.522 CO + #.174 CO2 + #.432 GLY + #.568 MGLY + 

#.652 xRCO3 + #.652 xHCHO + #.652 yR6OOH + #-

.872 XC 

9.66e-18 

 BP51 AFG2 + HV = PROD2 + #-1 XC Phot Set= AFG1 

 

BP52 AFG3 + OH = #.206 MACO3 + #.733 RO2C + #.117 

{RO2XC + zRNO3} + #.117 zRNO3 + #.561 xHO2 + 

#.117 xMECO3 + #.114 xCO + #.274 xGLY + #.153 

xMGLY + #.019 xBACL + #.195 xAFG1 + #.195 

xAFG2 + #.231 xIPRD + #.794 yR6OOH + #.236 XC 

9.35e-11 

BP53 AFG3 + O3 = #.471 OH + #.554 HO2 + #.013 MECO3 

+ #.258 RO2C + #.007 {RO2XC + zRNO3} + #.007 

zRNO3 + #.580 CO + #.190 CO2 + #.366 GLY + #.184 

MGLY + #.350 AFG1 + #.350 AFG2 + #.139 AFG3 + 

#.003 MACR + #.004 MVK + #.003 IPRD + #.095 

xHO2 + #.163 xRCO3 + #.163 xHCHO + #.095 

xMGLY + #.264 yR6OOH + #-.617 XC 

1.43e-17 

BP54 MACR + OH = #.5 MACO3 + #.5 {RO2C + xHO2} + 

#.416 xCO + #.084 xHCHO + #.416 xMEK + #.084 

xMGLY + #.5 yROOH + #-0.416 XC 

2.84e-11 8.00e-12 -0.76 

BP55 MACR + O3 = #.208 OH + #.108 HO2 + #.1 RO2C + 

#.45 CO + #.117 CO2 + #.1 HCHO + #.9 MGLY + 

#.333 HCOOH + #.1 xRCO3 + #.1 xHCHO + #.1 

yROOH + #-0.1 XC 

1.28e-18 1.40e-15 4.17 

BP56 MACR + NO3 = #.5 {MACO3 + RO2C + HNO3 + 

xHO2 + xCO} + #.5 yROOH + #1.5 XC + #.5 XN 

3.54e-15 1.50e-12 3.61 

 BP57 MACR + O3P = RCHO + XC 6.34e-12 
Table A-2 (continued) 

46 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

BP58 MACR + HV = #.33 OH + #.67 HO2 + #.34 MECO3 + 

#.33 MACO3 + #.33 RO2C + #.67 CO + #.34 HCHO + 

#.33 xMECO3 + #.33 xHCHO + #.33 yROOH 

Phot Set= MACR-06 

 

BP59 MVK + OH = #.975 RO2C + #.025 {RO2XC + 

zRNO3} + #.3 xHO2 + #.675 xMECO3 + #.3 xHCHO + 

#.675 xRCHO + #.3 xMGLY + yROOH + #-0.725 XC 

1.99e-11 2.60e-12 -1.21 

BP60 MVK + O3 = #.164 OH + #.064 HO2 + #.05 {RO2C + 

xHO2} + #.475 CO + #.124 CO2 + #.05 HCHO + #.95 

MGLY + #.351 HCOOH + #.05 xRCO3 + #.05 xHCHO 

+ #.05 yROOH + #-0.05 XC 

5.36e-18 8.50e-16 3.02 

 BP61 MVK + NO3 = #4 XC + XN (Slow) 

 BP62 MVK + O3P = #.45 RCHO + #.55 MEK + #.45 XC 4.32e-12 

BP63 MVK + HV = #.4 MEO2 + #.6 CO + #.6 PROD2 + #.4 

MACO3 + #-2.2 XC 

Phot Set= MVK-06 

 

BP64 IPRD + OH = #.289 MACO3 + #.67 {RO2C + xHO2} 

+ #.041 {RO2XC + zRNO3} + #.336 xCO + #.055 

xHCHO + #.129 xCCHO + #.013 xRCHO + #.15 

xMEK + #.332 xPROD2 + #.15 xGLY + #.174 xMGLY 

+ #-0.504 XC + #.711 yR6OOH 

6.19e-11 

BP65 IPRD + O3 = #.285 OH + #.4 HO2 + #.048 {RO2C + 

xRCO3} + #.498 CO + #.14 CO2 + #.124 HCHO + #.21 

MEK + #.023 GLY + #.742 MGLY + #.1 HCOOH + 

#.372 RCOOH + #.047 xCCHO + #.001 xHCHO + 

#.048 yR6OOH + #-.329 XC 

4.18e-18 

BP66 IPRD + NO3 = #.15 {MACO3 + HNO3} + #.799 

{RO2C + xHO2} + #.051 {RO2XC + zRNO3} + #.572 

xCO + #.227 xHCHO + #.218 xRCHO + #.008 xMGLY 

+ #.572 xRNO3 + #.85 yR6OOH + #.278 XN + #-.815 

XC 

1.00e-13 

BP67 IPRD + HV = #1.233 HO2 + #.467 MECO3 + #.3 

RCO3 + #1.233 CO + #.3 HCHO + #.467 CCHO + 

#.233 MEK + #-.233 XC 

Phot Set= MACR-06 

Lumped Parameter Organic Products 

BP68 PROD2 + OH = #.472 HO2 + #.473 RO2C + #.070 

RO2XC + #.070 zRNO3 + #.002 HCHO + #.001 CCHO 

+ #.143 RCHO + #.329 PROD2 + #.379 xHO2 + #.029 

xMECO3 + #.049 xRCO3 + #.211 xHCHO + #.083 

xCCHO + #.402 xRCHO + #.115 xMEK + #.007 

xPROD2 + #.528 yR6OOH + #.883 XC 

1.55e-11 

BP69 PROD2 + HV = #.400 MECO3 + #.600 RCO3 + #1.590 

RO2C + #.086 RO2XC + #.086 zRNO3 + #.914 xHO2 

+ #.303 xHCHO + #.163 xCCHO + #.780 xRCHO + 

yR6OOH + #-.085 XC 

Phot Set= MEK-06, qy= 4.86e-3 

 
Table A-2 (continued) 

47 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

BP70 RNO3 + OH = #.019 NO2 + #.189 HO2 + #.976 RO2C 

+ #.175 RO2XC + #.175 zRNO3 + #.001 RCHO + 

#.010 MEK + #.007 PROD2 + #.189 RNO3 + #.312 

xNO2 + #.305 xHO2 + #.011 xHCHO + #.428 xCCHO 

+ #.036 xRCHO + #.004 xACET + #.170 xMEK + 

#.030 xPROD2 + #.305 xRNO3 + #.792 yR6OOH + 

#.175 XN + #.054 XC 

7.20e-12 

BP71 RNO3 + HV = NO2 + #.344 HO2 + #.721 RO2C + 

#.102 RO2XC + #.102 zRNO3 + #.074 HCHO + #.214 

CCHO + #.074 RCHO + #.124 MEK + #.190 PROD2 + 

#.554 xHO2 + #.061 xHCHO + #.230 xCCHO + #.063 

xRCHO + #.008 xACET + #.083 xMEK + #.261 

xPROD2 + #.656 yR6OOH + #.396 XC 

Phot Set= IC3ONO2 

Steady-State Peroxy Radical operators (for formation of organic product species formed in 

peroxy + NO reactions) [c]

 

 PO01 xHCHO = HCHO k is variable parameter: RO2RO 

 PO02 xHCHO = XC k is variable parameter: RO2XRO 

 PO03 xCCHO = CCHO k is variable parameter: RO2RO 

 PO04 xCCHO = #2 XC k is variable parameter: RO2XRO 

 PO05 xRCHO = RCHO k is variable parameter: RO2RO 

 PO06 xRCHO = #3 XC k is variable parameter: RO2XRO 

 PO07 xACET = ACET k is variable parameter: RO2RO 

 PO08 xACET = #3 XC k is variable parameter: RO2XRO 

 PO09 xMEK = MEK k is variable parameter: RO2RO 

 PO10 xMEK = #4 XC k is variable parameter: RO2XRO 

 PO11 xPROD2 = PROD2 k is variable parameter: RO2RO 

 PO12 xPROD2 = #6 XC k is variable parameter: RO2XRO 

 PO13 xGLY = GLY k is variable parameter: RO2RO 

 PO14 xGLY = #2 XC k is variable parameter: RO2XRO 

 PO15 xMGLY = MGLY k is variable parameter: RO2RO 

 PO16 xMGLY = #3 XC k is variable parameter: RO2XRO 

 PO17 xBACL = BACL k is variable parameter: RO2RO 

 PO18 xBACL = #4 XC k is variable parameter: RO2XRO 

 PO19 xBALD = BALD k is variable parameter: RO2RO 

 PO20 xBALD = #7 XC k is variable parameter: RO2XRO 

 PO21 xAFG1 = AFG1 k is variable parameter: RO2RO 

 PO22 xAFG1 = #5 XC k is variable parameter: RO2XRO 

 PO23 xAFG2 = AFG2 k is variable parameter: RO2RO 

 PO24 xAFG2 = #5 XC k is variable parameter: RO2XRO 

 PO25 xAFG3 = AFG3 k is variable parameter: RO2RO 

 PO26 xAFG3 = #7 XC k is variable parameter: RO2XRO 

 PO27 xMACR = MACR k is variable parameter: RO2RO 

 PO28 xMACR = #4 XC k is variable parameter: RO2XRO 

 PO29 xMVK = MVK k is variable parameter: RO2RO 

 PO30 xMVK = #4 XC k is variable parameter: RO2XRO 

 PO31 xIPRD = IPRD k is variable parameter: RO2RO 

 PO32 xIPRD = #5 XC k is variable parameter: RO2XRO 
Table A-2 (continued) 

48 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

 PO33 xRNO3 = RNO3 k is variable parameter: RO2RO 

 PO34 xRNO3 = #6 XC + XN k is variable parameter: RO2XRO 

 PO35 xHCOOH = HCOOH k is variable parameter: RO2RO 

 PO36 xHCOOH = XC k is variable parameter: RO2XRO 

 PO37 xCCOOH = CCOOH k is variable parameter: RO2RO 

 PO38 xCCOOH = #2 XC k is variable parameter: RO2XRO 

 PO39 xRCOOH = RCOOH k is variable parameter: RO2RO 

 PO40 xRCOOH = #3 XC k is variable parameter: RO2XRO 

Steady-State Peroxy Radical operators (for formation of organic nitrates formed in peroxy + NO 

reactions) [d]

 PO41 zRNO3 = RNO3 + #-1 XN k is variable parameter: RO2NO 

 PO42 zRNO3 = PROD2 + HO2 k is variable parameter: RO22NN 

 PO43 zRNO3 = #6 XC k is variable parameter: RO2XRO 

Steady-State Peroxy Radical operators (for formation of hydroperoxides formed in peroxy + HO2

reactions) [e]

 PO44 yROOH = ROOH + #-3 XC k is variable parameter: RO2HO2 

 PO45 yROOH = MEK + #-4 XC k is variable parameter: RO2RO2M

 PO46 yROOH = k is variable parameter: RO2RO 

 PO47 yR6OOH = R6OOH + #-6 XC k is variable parameter: RO2HO2 

 PO48 yR6OOH = PROD2 + #-6 XC k is variable parameter: RO2RO2M

 PO49 yR6OOH = k is variable parameter: RO2RO 

 PO50 yRAOOH = RAOOH + #-8 XC k is variable parameter: RO2HO2 

 PO51 yRAOOH = PROD2 + #-6 XC k is variable parameter: RO2RO2M

 PO52 yRAOOH = k is variable parameter: RO2RO 

Explicitly Represented Primary Organics 

 BE01 CH4 + OH = H2O + MEO2 6.62e-15 1.85e-12 3.36 

 

 BE02 8.15e-12 Falloff, F=0.60, N=1.00

 0: 1.00e-28 0.00 -4.50

 

ETHENE + OH = RO2C + xHO2 + #1.61 xHCHO + 

#.195 xCCHO + yROOH 

inf: 8.80e-12 0.00 -0.85

BE03 ETHENE + O3 = #.16 OH + #.16 HO2 + #.51 CO + 

#.12 CO2 + HCHO + #.37 HCOOH 

1.68e-18 9.14e-15 5.13 

BE04 ETHENE + NO3 = RO2C + xHO2 + xRCHO + 

yROOH + #-1 XC + XN 

2.24e-16 3.30e-12 5.72 2.00

BE05 ETHENE + O3P = #.8 HO2 + #.51 MEO2 + #.29 RO2C 

+ #.51 CO + #.1 CCHO + #.29 xHO2 + #.278 xCO + 

#.278 xHCHO + #.012 xGLY + #.29 yROOH + #.2 XC

7.43e-13 1.07e-11 1.59 

 

BE06 ISOPRENE + OH = #.986 RO2C + #.093 {RO2XC + 

zRNO3} + #.907 xHO2 + #.624 xHCHO + #.23 

xMACR + #.32 xMVK + #.357 xIPRD + yR6OOH + #-

0.167 XC 

9.96e-11 2.54e-11 -0.81 

BE07 ISOPRENE + O3 = #.266 OH + #.066 HO2 + #.192 

RO2C + #.008 {RO2XC + zRNO3} + #.275 CO + #.122

CO2 + #.4 HCHO + #.1 PROD2 + #.39 MACR + #.16 

MVK + #.15 IPRD + #.204 HCOOH + #.192 

{xMACO3 + xHCHO} + #.2 yR6OOH + #-0.559 XC 

1.34e-17 7.86e-15 3.80 
Table A-2 (continued) 

49 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

BE08 ISOPRENE + NO3 = #.936 RO2C + #.064 {RO2XC + 

zRNO3} + #.749 xHO2 + #.187 xNO2 + #.936 xIPRD + 

yR6OOH + #-0.064 XC + #.813 XN 

6.81e-13 3.03e-12 0.89 

BE09 ISOPRENE + O3P = #.25 MEO2 + #.24 RO2C + #.01 

{RO2XC + zRNO3} + #.75 PROD2 + #.24 xMACO3 + 

#.24 xHCHO + #.25 yR6OOH + #-1.01 XC 

3.50e-11 

 

BE10 ACETYLEN + OH = #.7 OH + #.3 HO2 + #.3 CO + #.7 

GLY + #.3 HCOOH 

7.56e-13 Falloff, F=0.60, N=1.00

BE11 ACETYLEN + O3 = #.5 OH + #1.5 HO2 + #1.5 CO + 

#.5 CO2 

1.16e-20 1.00e-14 8.15 

 

BE12 BENZENE + OH = #.116 OH + #.29 {RO2C + xHO2} 

+ #.024 {RO2XC + zRNO3} + #.57 {HO2 + CRES} + 

#.116 AFG3 + #.290 xGLY + #.029 xAFG1 + #.261 

xAFG2 + #.314 yRAOOH + #-.976 XC 

1.22e-12 2.33e-12 0.38 

Reactions of Compounds represented explicitly in the chamber simulations

CH05 N-C4 + OH = #1.334 RO2C + #.079 RO2XC + #.079 

zRNO3 + #.921 xHO2 + #.632 xCCHO + #.120 xRCHO 

+ #.485 xMEK + yROOH + #-.038 XC 

2.38e-12 1.63e-12 -0.23 

CH07 N-C6 + OH = #1.562 RO2C + #.225 RO2XC + #.225 

zRNO3 + #.775 xHO2 + #.011 xCCHO + #.113 xRCHO 

+ #.688 xPROD2 + yR6OOH + #.161 XC 

5.25e-12 7.62e-12 0.22 

CH09 N-C8 + OH = #1.432 RO2C + #.354 RO2XC + #.354 

zRNO3 + #.646 xHO2 + #.024 xRCHO + #.622 

xPROD2 + yR6OOH + #2.072 XC 

8.16e-12 2.45e-12 -0.72 

CH11 PROPENE + OH = #.984 RO2C + #.016 RO2XC + 

#.016 zRNO3 + #.984 xHO2 + #.984 xHCHO + #.984 

xCCHO + yROOH + #-.048 XC 

2.60e-11 4.85e-12 -1.00 

CH12 PROPENE + O3 = #.350 OH + #.165 HO2 + #.355 

MEO2 + #.525 CO + #.215 CO2 + #.500 HCHO + #.500 

CCHO + #.185 HCOOH + #.075 CCOOH + #.070 XC 

1.05e-17 5.51e-15 3.73 

CH13 PROPENE + NO3 = #.949 RO2C + #.051 RO2XC + 

#.051 zRNO3 + #.949 xHO2 + yROOH + #2.694 XC + 

XN 

9.73e-15 4.59e-13 2.30 

CH14 PROPENE + O3P = #.450 RCHO + #.550 MEK + #-

.550 XC 

4.01e-12 1.02e-11 0.56 

CH16 T-2-BUTE + OH = #.965 RO2C + #.035 RO2XC + 

#.035 zRNO3 + #.965 xHO2 + #1.930 xCCHO + 

yROOH + #-.070 XC 

6.32e-11 1.01e-11 -1.09 

CH17 T-2-BUTE + O3 = #.540 OH + #.170 HO2 + #.710 

MEO2 + #.540 CO + #.310 CO2 + CCHO + #.150 

CCOOH + #.140 XC 

1.95e-16 6.64e-15 2.10 

CH18 T-2-BUTE + NO3 = #.920 RO2C + #.080 RO2XC + 

#.080 zRNO3 + #.705 xNO2 + #.215 xHO2 + #1.410 

xCCHO + #.215 xRNO3 + yROOH + #-.590 XC + 

#.080 XN 

3.93e-13 1.10e-13 -0.76 

 CH19 T-2-BUTE + O3P = MEK 1.99e-11 1.09e-11 -0.36 
Table A-2 (continued) 

50 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

CH21 TOLUENE + OH = #.312 {OH + AFG3} + #.181 {HO2 

+ CRES} + #.454 {RO2C + xHO2} + #.054 {RO2XC 

+zRNO3} + #.238 xGLY + #.151 xMGLY + #.065 

xBALD + #.195 xAFG1 + #.195 xAFG2 + #.073 

yR6OOH + #.435 yRAOOH + #-.109 XC 

5.58e-12 1.81e-12 -0.67 

CH23 M-XYLENE + OH = #.239 {OH + AFG3} + #.159 

{HO2 + CRES} + #.52 {RO2C +xHO2} + #.082 

{RO2XC + zRNO3} + #.100 xGLY + #.380 xMGLY + 

#.041 xBALD + #.336 xAFG1 + #.144 xAFG2 + #.047 

yR6OOH + #.555 yRAOOH+ #.695 XC 

2.31e-11 

Reactions of Ethane used in its Atmospheric Reactivity Simulations

 C201 ETHANE + OH = RO2C + xHO2 + xCCHO + yROOH 2.54E-13 1.34E-12 0.992 2.0 

Reactions of Lumped Species used in Atmospheric Reactivity Simulations

 BL01 ALK1 + OH = RO2C + xHO2 + xCCHO + yROOH 2.54e-13 1.34e-12 0.99 

BL02 ALK2 + OH = #.965 RO2C + #.035 {RO2XC + 

zRNO3} + #.965 xHO2 + #.261 xRCHO + #.704 

xACET + yROOH + #-.105 XC 

1.11e-12 1.49e-12 0.17 

BL03 ALK3 + OH = #1.253 RO2C + #.07 {RO2XC + 

zRNO3} + #.694 xHO2 + #.236 xTBUO + #.026 

xHCHO + #.445 xCCHO + #.122 xRCHO + #.024 

xACET + #.332 xMEK + yROOH + #-.046 XC 

2.31e-12 1.51e-12 -0.25 

BL04 ALK4 + OH = #1.773 RO2C + #.144 {RO2XC + 

zRNO3} + #.834 xHO2 + #.011 xMEO2 + #.011 

xMECO3 + #.002 xCO + #.030 xHCHO + #.454 

xCCHO + #.242 xRCHO + #.442 xACET + #.110 

xMEK + #.128 xPROD2 + yR6OOH + #-.097 XC 

4.26e-12 3.67e-12 -0.09 

BL05 ALK5 + OH = #1.597 RO2C + #.348 {RO2XC + 

zRNO3} + #.652 xHO2 + #.037 xHCHO + #.099 

xCCHO + #.199 xRCHO + #.066 xACET + #.080 

xMEK + #.425 xPROD2 + yR6OOH + #2.012 XC 

9.22e-12 2.65e-12 -0.74 

 

BL06 OLE1 + OH = #1.138 RO2C + #.095 {RO2XC + 

zRNO3} + #.904 xHO2 + #.001 xMEO2 + #.700 

xHCHO + #.301 xCCHO + #.470 xRCHO + #.005 

xACET + #.119 xPROD2 + #.026 xMACR + #.008 

xMVK + #.006 xIPRD + yROOH + #.822 XC 

3.29e-11 6.18e-12 -1.00 

BL07 OLE1 + O3 = #.193 OH + #.116 HO2 + #.104 MEO2 + 

#.063 RO2C + #.004 {RO2XC + zRNO3} + #.368 CO + 

#.125 CO2 + #.500 HCHO + #.147 CCHO + #.353 

RCHO + #.006 MEK + #.189 PROD2 + #.185 HCOOH 

+ #.022 CCOOH + #.112 RCOOH + #.040 xHO2 + 

#.007 xCCHO + #.031 xRCHO + #.002 xACET + #.044 

yR6OOH + #.69 XC 

1.09e-17 3.15e-15 3.38 

BL08 OLE1 + NO3 = #1.312 RO2C + #.176 {RO2XC + 

zRNO3} + #.824 xHO2 + #.009 xCCHO + #.002 

xRCHO + #.024 xACET + #.546 xRNO3 + yR6OOH + 

#.454 XN + #.572 XC 

1.44e-14 4.73e-13 2.08 
Table A-2 (continued) 

51 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

BL09 OLE1 + O3P = #.450 RCHO + #.437 MEK + #.113 

PROD2 + #1.224 XC 

5.02e-12 1.49e-11 0.65 

 

BL10 OLE2 + OH = #.966 RO2C + #.086 {RO2XC + 

zRNO3} + #.914 xHO2 + #.209 xHCHO + #.787 

xCCHO + #.483 xRCHO + #.136 xACET + #.076 

xMEK + #.021 xPROD2 + #.027 xMACR + #.002 

xMVK + #.037 xIPRD + yR6OOH + #.113 XC 

6.41e-11 1.26e-11 -0.97 

BL11 OLE2 + O3 = #.421 OH + #.093 HO2 + #.290 MEO2 + 

#.199 RO2C + #.003 {RO2XC + zRNO3} + #.296 CO + 

#.162 CO2 + #.152 HCHO + #.426 CCHO + #.316 

RCHO + #.048 ACET + #.031 MEK + #.042 PROD2 + 

#.028 MACR + #.021 MVK + #.033 HCOOH + #.061 

CCOOH + #.222 RCOOH + #.039 xHO2 + #.147 

xMECO3 + #.007 xRCO3 + #.108 xHCHO + #.066 

xCCHO + #.019 xRCHO + #.196 yR6OOH + #.133 XC

1.24e-16 8.15e-15 2.49 

BL12 OLE2 + NO3 = #1.185 RO2C + #.136 {RO2XC + 

zRNO3} + #.409 xNO2 + #.423 xHO2 + #.033 xMEO2 

+ #.074 xHCHO + #.546 xCCHO + #.153 xRCHO + 

#.110 xACET + #.002 xMEK + #.026 xMVK + #.007 

xIPRD + #.322 xRNO3 + yR6OOH + #.270 XN + #.117 

XC 

7.70e-13 2.15e-13 -0.76 

BL13 OLE2 + O3P = #.014 HO2 + #.013 RO2C + #.074 

RCHO + #.709 MEK + #.203 PROD2 + #.007 xHO2 + 

#.007 xMACO3 + #.006 xCO + #.006 xMACR + #.014 

yR6OOH + #.666 XC 

2.06e-11 1.43e-11 -0.22 

 

BL14 ARO1 + OH = #.283 OH + #.166 HO2 + #.483 RO2C + 

#.068 {RO2XC + zRNO3} + #.166 CRES + #.283 

AFG3 + #.483 xHO2 + #.217 xGLY + #.138 xMGLY + 

#.049 xBALD + #.079 xPROD2 + #.164 xAFG1 + #.192 

xAFG2 + #.150 yR6OOH + #.402 yRAOOH+ #.004 XC

6.18e-12 

BL15 ARO2 + OH = #.199 OH + #.108 HO2 + #.582 RO2C + 

#.111 RO2XC + #.111 zRNO3 + #.108 CRES + #.199 

AFG3 + #.582 xHO2 + #.111 xGLY + #.291 xMGLY + 

#.104 xBACL + #.033 xBALD + #.042 xPROD2 + 

#.223 xAFG1 + #.211 xAFG2 + #.074 xAFG3 + #.090 

yR6OOH + #.603 yRAOOH+ #1.503 XC 

2.20e-11 

 

BL16 TERP + OH = #1.147 RO2C + #.2 {RO2XC + zRNO3} 

+ #.759 xHO2 + #.042 xRCO3 + #.002 xCO + #.264 

xHCHO + #.533 xRCHO + #.036 xACET + #.005 

xMEK + #.255 xPROD2 + #.009 xMGLY + #.014 

xBACL + #.002 xMVK + #.001 xIPRD + yR6OOH + 

#5.055 XC 

7.98e-11 1.87e-11 -0.86 
Table A-2 (continued) 

52 

 Rate Parameters [b] 

 Label Reaction and Products [a] k(300) A Ea B 

BL17 TERP + O3 = #.585 OH + #.052 HO2 + #.875 RO2C + 

#.203 RO2XC + #.203 zRNO3 + #.166 CO + #.045 CO2 

+ #.079 HCHO + #.004 MEK + #.409 PROD2 + #.107 

HCOOH + #.043 RCOOH + #.067 xHO2 + #.126 

xMECO3 + #.149 xRCO3 + #.019 xCO + #.150 xHCHO 

+ #.220 xRCHO + #.165 xACET + #.001 xGLY + #.002 

xMGLY + #.055 xBACL + #.001 xMACR + #.001 

xIPRD + #.545 yR6OOH + #3.526 XC 

6.99e-17 1.02e-15 1.60 

BL18 TERP + NO3 = #1.508 RO2C + #.397 RO2XC + #.397 

zRNO3 + #.422 xNO2 + #.162 xHO2 + #.019 xRCO3 + 

#.010 xCO + #.017 xHCHO + #.001 xCCHO + #.509 

xRCHO + #.174 xACET + #.001 xMGLY + #.003 

xMACR + #.001 xMVK + #.002 xIPRD + #.163 xRNO3 

+ yR6OOH + #4.476 XC + #.415 XN 

6.53e-12 1.28e-12 -0.97 

BL19 TERP + O3P = #.147 RCHO + #.853 PROD2 + #4.441 

XC 

3.71e-11 

[a] Format of reaction listing: “=“ separates reactants from products; “#number” indicates stoichiometric 

coefficient, “#coefficient {product list}” means that the stoichiometric coefficient is applied to all the 

products listed. 

[b] Except as indicated, the rate constants are given by k(T) = A · (T/300)B

 · e-Ea/RT, where the units of k 

and A are cm3

 molec-1 s-1, Ea are kcal mol-1, T is oK, and R=0.0019872 kcal mol-1 deg-1. If A, Ea, and 

B are not given the rate constants are assumed to be temperature independent. The following special 

rate constant expressions are used: 

Phot Set = name: The absorption cross sections and (if applicable) quantum yields for the photolysis 

reaction are given by Carter (2009). Here, “name” indicates the photolysis set used. If a 

“qy=number” notation is given, the number given is the overall quantum yield, which is assumed to 

be wavelength independent. Photolysis rates used in chamber and ambient simulations are given in 

Table A-3. 

Falloff: The rate constant as a function of temperature and pressure is calculated using k(T,M) = 

{k0(T)·[M]/[1 + k0(T)·[M]/kinf(T)]}· FZ

, where Z = {1 + [log10{k0(T)·[M])/kinf(T)}/N]2 }-1, [M] 

is the total pressure in molecules cm-3, F and N are as indicated on the table, and the temperature 

dependences of k0 and kinf are as indicated on the table. 

k = k0+k3M(1+k3M/k2): The rate constant as a function of temperature and pressure is calculated 

using k(T,M) = k0(T) + k3(T)·[M] ·(1 + k3(T)·[M]/k2(T)), where [M] is the total bath gas (air) 

concentration in molecules cm-3, and the temperature dependences for k0, k2 and k3 are as 

indicated on the table. 

k = k1 + k2 [M]: The rate constant as a function of temperature and pressure is calculated using 

k(T,M) = k1(T) + k2(T)·[M], where [M] is the total bath gas (air) concentration in molecules cm-3, 

and the temperature dependences for k1, and k2 are as indicated on the table. 

Same K as Rxn xx: Uses the same rate constant as the reaction in the base mechanism with the same 

label. 

k is variable parameter name: The rate constant is calculated using variable parameters that are 

calculated using concentrations of various species. See Footnotes [c], [d], and [e], below. 

 [c] The xPROD chemical operator species are used to represent the formation of radicals and products 

from alkoxy radicals formed in the reactions of peroxy radicals with NO, NO3, and other peroxy 
Table A-2 (continued) 

53 

radicals. These products are not formed when peroxy radicals react with HO2 and acyl peroxy 

radicals, since those reactions are assumed not form alkoxy radicals, but instead form 

hydroperoxides or H-shift disproportion products that are represented by separate yROOH chemical 

operator species, discussed in a separate footnote. The reactions of peroxy radicals with other peroxy 

radicals are assumed to form alkoxy radicals 50% of the time, so the products from alkoxy radical 

reactions are represented as being formed in 50% yields in these reactions. The consumption and 

products formed from these species can be represented in several ways. The most straightforward 

method is to include a reaction for each of the types of peroxy radical reactions, as follows: 

 xPROD + NO → NO + PROD 

 xPROD + HO2 → HO2 

 xPROD + NO3 → NO3 + PROD 

 xPROD + MECO3 → MECO3 (& similar reactions for RCO3, BZCO3, and MACO3) 

 xPROD + RO2C → RO2C + 1/2 PROD (& a similar reaction for RO2XC) 

 where "PROD" represents the product species for the operator (e.g, HO2 for xHO2). The rate 

constants for these reactions should be the same as the rate constant for the corresponding reactions 

of RO2C or RO2XC. This is a somewhat cumbersome method because it requires 9 reactions for 

each of the many xPROD species. An alternative method, implemented in this table, uses the 

coefficient "RO2RO" to determine the rate of formation of the product species and "RO2XRO" to 

represent processes where the product is not formed. These are calculated as follows, where the 

k(RO2+..)'s refer to the rate constants for the reactions of RO2C or RO2XC with the indicated 

reactant. 

 RO2RO = k(RO2+NO)[NO] + k(RO2+NO3)[NO3] + 0.5 k(RO2+MEO2)[MEO2] + 

 0.5 k(RO2+RO2){[RO2C]+[RO2XC]) 

 RO2XRO = k(RO2+HO2)[HO2] + k(RO2+MECO3){[MECO3]+[RCO3]+[BZCO3]+ 

 [MACO3]) + 0.5 k(RO2+MEO2)[MEO2] + 0.5 k(RO2+RO2){[RO2C]+ [RO2XC]) 

 The steady state approximation must be used for these operators when this representation is used, 

and the operators must not be allowed to be diluted or transported. 

[d] The zRNO3 chemical operator species is used to represent the formation organic nitrates formed 

when peroxy radicals react with NO, or formation of of radicals and products from alkoxy radicals 

formed in the reactions of peroxy radicals with NO3 and other peroxy radicals. These products are 

not formed when peroxy radicals react with HO2 and acyl peroxy radicals, since those reactions are 

assumed not form organic nitrates or alkoxy radicals, but instead form hydroperoxides or H-shift 

disproportion products that are represented by separate yROOH chemical operator species, discussed 

in a separate footnote. At present the mechanism has only one zRNO3 operator to correspond to the 

single lumped organic nitrate model species, but other such operators can be added if it is desired to 

have separate organic nitrate model species, such as, for example, those to represent semi-volatile 

organic nitrates that may contribute to SOA. In the case of zRNO3, the products resulting if alkoxy 

radicals are formed in the RCO3 or RO2 reactions would depend on reactant and individual radicals, 

and are approximated by PROD2 and HO2 (as might occur following the reaction of a peroxy radical 

with O2 to form HO2 and a ketone species). As with the xPROD species, the consumption and 

products formed from these species can be represented in several ways, with the most 

straightforward method being to include a reaction for each of the types of peroxy radical reactions, 

as follows: 

 zRNO3 + NO → NO + RNO3 

 zRNO3 + HO2 → HO2 

 zRNO3 + NO3 → NO3 + PROD2 + HO2 

 zRNO3 + MECO3 → MECO3 (& similar reactions for RCO3, BZCO3, and MACO3) 

 zRNO3 + RO2C → RO2C + 1/2 {PROD2 + HO2} (& a similar reaction for RO2XC) 
Table A-2 (continued) 

54 

 The rate constants for these reactions should be the same as the rate constant for the corresponding 

reactions of RO2C or RO2XC. As with xPROD, an alternative method, requiring fewer reactions, is 

implemented in this table. In this case, the coefficient "RO2NO" is used to determine the rate of 

formation of organic nitrates, "RO22NN" is used to determine the rate of formation of the alkoxy 

radical products, and "RO2XRO" is used to represent processes where these products are is not 

formed, and is the same as used for xPROD. These are calculated as follows, where the k(RO2+..)'s 

refer to the rate constants for the reactions of RO2C or RO2XC with the indicated reactant. 

 RO2NO = k(RO2+NO)[NO] 

 RO22NN = k(RO2+NO3)[NO3] + 0.5 k(RO2+MEO2)[MEO2] + 

 0.5 k(RO2+RO2){[RO2C]+ [RO2XC]) 

 RO2XRO = k(RO2+HO2)[HO2] + k(RO2+MECO3){[MECO3]+[RCO3]+[BZCO3]+ 

 [MACO3]) + 0.5 k(RO2+MEO2)[MEO2] + 0.5 k(RO2+RO2){[RO2C]+ [RO2XC]) 

 (same as used for xPROD) 

 The steady state approximation must be used for these operators when this representation is used, 

and the operators must not be allowed to be diluted or transported. 

[e] The yROOH chemical operator species is used to represent the formation of organic hydroperoxides 

formed with peroxy radicals react with HO2, or of H-shift disproportionation products formed when 

peroxy radicals react with acyl peroxy radicals or (in 50% yields) with other peroxy radicals. Note 

that the products formed when peroxy radicals react to form alkoxy radicals or organic nitrates (in 

the NO reaction) are represented using separate xPROD or zRNO3 species, and together these three 

types of operators represent all the products and radicals formed. Separate such yROOH species are 

used to represent formation of hydroperoxides or H-shift disproportion products in different 

molecular weight ranges or volatilities, and more can be added as needed for appropriate predictions 

of SOA formation. The hydroperoxide formed in the HO2 reaction is represented by either ROOH, 

R6OOH, or RAOOH, and the H-shift disproportion products are represented by either MEK (for 

yROOH) or PROD2 (for the others). As with the xPROD and zRNO3 species, the consumption and 

products formed from these species can be represented in several ways, with the most 

straightforward method being to include a reaction for each of the types of peroxy radical reactions, 

as follows for yROOH (the reactions for the other two are analogous). 

 yROOH + NO → NO 

 yROOH + HO2 → HO2 + ROOH 

 yROOH + NO3 → NO3 

 yROOH + MECO3 → MECO3 + MEK (& similar reactions for RCO3, BZCO3, and 

 MACO3) 

 yROOH + RO2C → RO2C + 1/2 MEK (& a similar reaction for RO2XC) 

 The rate constants for these reactions should be the same as the rate constant for the corresponding 

reactions of RO2C or RO2XC. As with the other operators, an alternative method, requiring fewer 

reactions, is implemented in this table. In this case, the coefficient "RO2HO2" is used to determine 

the rate of formation of organic hydroperoxides, "RO2RO2M" to determine the rate of formation of 

H-shift disproportion products, and "RO2RO" is used to represent processes where these products 

are is not formed. Note that the latter is the same as the coefficient that is used to represent the 

formation products from the xPROD species. These are calculated as follows, where the k(RO2+..)'s 

refer to the rate constants for the reactions of RO2C or RO2XC with the indicated reactant. 

 RO2HO2 = k(RO2+HO2)[HO2] 

 RO2RO2M = k(RO2+MECO3){[MECO3]+[RCO3]+[BZCO3]+ [MACO3]) + 0.5 

 k(RO2+MEO2)[MEO2] + 0.5 k(RO2+RO2){[RO2C]+ [RO2XC]) 
Table A-2 (continued) 

55 

 RO2RO = k(RO2+NO)[NO] + k(RO2+NO3)[NO3] + 0.5 k(RO2+MEO2)[MEO2] + 

 0.5 k(RO2+RO2){[RO2C]+[RO2XC]) 

 The steady state approximation must be used for these operators when this representation is used, 

and the operators must not be allowed to be diluted or transported. 

Table A-3. Summary of photolysis rates used in chamber and ambient simulations. 

Photolysis rates (min-1) 

Phot File Cham Ambient simulations (as function of solar zenith angle) [b] ber 

[a] Z=0 Z=10 Z=20 Z=30 Z=40 Z=50 Z=60 Z=70 Z=78 Z=86 

Base Mechanism [c] 

NO2-06 0.115 0.723 0.718 0.702 0.676 0.631 0.560 0.430 0.253 0.093 0.005 

NO3NO-06 2.44e-4 1.91e+0 1.91e+0 1.90e+0 1.89e+0 1.87e+0 1.82e+0 1.65e+0 1.37e+0 9.15e-1 4.85e-1

NO3NO2-6 4.83e-2 1.54e+1 1.54e+1 1.53e+1 1.52e+1 1.49e+1 1.44e+1 1.29e+1 1.03e+1 6.50e+0 2.80e+0

O3O1D-06 1.83e-4 3.06e-3 2.96e-3 2.68e-3 2.24e-3 1.67e-3 1.06e-3 4.91e-4 1.33e-4 2.01e-5 3.66e-7

O3O3P-06 4.84e-4 3.66e-2 3.66e-2 3.62e-2 3.57e-2 3.48e-2 3.32e-2 2.95e-2 2.37e-2 1.57e-2 8.36e-3

HONO-06 2.81e-2 1.14e-1 1.13e-1 1.10e-1 1.06e-1 9.78e-2 8.54e-2 6.38e-2 3.55e-2 1.18e-2 4.32e-4

HNO3 4.42e-6 5.40e-5 5.28e-5 4.91e-5 4.31e-5 3.49e-5 2.50e-5 1.40e-5 4.99e-6 9.91e-7 2.29e-8

HNO4-06 6.66e-5 5.42e-4 5.32e-4 5.01e-4 4.52e-4 3.81e-4 2.90e-4 1.77e-4 7.28e-5 1.70e-5 4.56e-7

H2O2 9.00e-5 5.64e-4 5.56e-4 5.29e-4 4.86e-4 4.21e-4 3.33e-4 2.14e-4 9.43e-5 2.35e-5 6.64e-7

PAN 7.17e-6 6.12e-5 6.00e-5 5.65e-5 5.08e-5 4.26e-5 3.22e-5 1.95e-5 7.90e-6 1.81e-6 4.80e-8

HCHOR-06 2.53e-4 2.76e-3 2.72e-3 2.59e-3 2.36e-3 2.03e-3 1.58e-3 9.85e-4 4.05e-4 9.08e-5 2.35e-6

HCHOM-06 6.12e-4 3.12e-3 3.08e-3 2.97e-3 2.77e-3 2.47e-3 2.02e-3 1.37e-3 6.41e-4 1.69e-4 5.00e-6

CCHO_R 2.53e-5 4.16e-4 4.06e-4 3.75e-4 3.27e-4 2.60e-4 1.81e-4 9.50e-5 2.99e-5 4.86e-6 8.30e-8

C2CHO 1.05e-4 1.40e-3 1.37e-3 1.28e-3 1.14e-3 9.29e-4 6.74e-4 3.80e-4 1.36e-4 2.62e-5 5.79e-7

ACET-06 3.85e-6 6.47e-5 6.28e-5 5.69e-5 4.78e-5 3.60e-5 2.32e-5 1.10e-5 3.05e-6 4.50e-7 7.35e-9

MEK-06 6.96e-5 9.66e-4 9.45e-4 8.80e-4 7.78e-4 6.33e-4 4.56e-4 2.54e-4 8.86e-5 1.66e-5 3.53e-7

COOH 7.11e-5 3.94e-4 3.89e-4 3.71e-4 3.42e-4 2.99e-4 2.40e-4 1.58e-4 7.21e-5 1.89e-5 5.51e-7

GLY-07R 9.60e-4 9.06e-3 9.00e-3 8.78e-3 8.44e-3 7.86e-3 6.97e-3 5.39e-3 3.29e-3 1.35e-3 1.31e-4

GLY-07M 4.40e-4 3.18e-3 3.14e-3 3.00e-3 2.78e-3 2.44e-3 1.98e-3 1.33e-3 6.41e-4 1.91e-4 8.80e-6

MGLY-06 1.02e-3 1.56e-2 1.56e-2 1.52e-2 1.47e-2 1.38e-2 1.24e-2 9.83e-3 6.27e-3 2.72e-3 2.87e-4

BACL-07 2.06e-3 2.67e-2 2.66e-2 2.61e-2 2.54e-2 2.40e-2 2.18e-2 1.75e-2 1.12e-2 4.81e-3 4.67e-4

BALD-06 1.32e-2 5.10e-2 5.05e-2 4.88e-2 4.61e-2 4.17e-2 3.52e-2 2.49e-2 1.26e-2 3.71e-3 1.17e-4

AFG1 6.82e-2 3.87e-1 3.83e-1 3.70e-1 3.50e-1 3.17e-1 2.69e-1 1.94e-1 1.04e-1 3.51e-2 1.99e-3

MACR-06 3.43e-5 1.97e-4 1.94e-4 1.86e-4 1.72e-4 1.51e-4 1.21e-4 7.98e-5 3.64e-5 9.42e-6 2.74e-7

MVK-06 1.32e-5 7.50e-5 7.40e-5 7.07e-5 6.54e-5 5.73e-5 4.60e-5 3.02e-5 1.37e-5 3.51e-6 1.01e-7

IC3ONO2 1.82e-5 2.35e-4 2.30e-4 2.15e-4 1.91e-4 1.57e-4 1.15e-4 6.57e-5 2.41e-5 4.80e-6 1.11e-7

 

[a] Photolysis rates for a chamber experiment with blacklight light source. The chamber photolysis rates 

are for the experiments carried out for this project. 

[b] See Carter (1994) for documentation of solar actinic fluxes used in the atmospheric reactivity 

calculations. 

[c] Calculated using absorption coefficients and cross sections given by Carter (2009)