Measured Mass-Normalized Optical Cross Sections 

For Aerosolized Organophosphorus Chemical 

Warfare Simulants 

by Kristan P. Gurton, Melvin Felton, 

Rachid Dahmani, and David Ligon 

ARL-TR-4220 August 2007 

Approved for public release; distribution unlimited. 
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Army Research Laboratory 

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ARL-TR-4220 August 2007 

Measured Mass-Normalized Optical Cross Sections 

For Aerosolized Organophosphorus Chemical 

Warfare Simulants 

Kristan P. Gurton, Melvin Felton 

Rachid Dahmani, and David Ligon 

Computational and Information Sciences Directorate, ARL 

Approved for public release; distribution unlimited. 
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Measured Mass-Normalized Optical Cross Sections For Aerosolized 

Organophosphorus Chemical Warfare Simulants 

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Kristan P. Gurton, Melvin Felton, Rachid Dahmani, and David Ligon 

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U.S. Army Research Laboratory 

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14. ABSTRACT 

We present newly measured results of an ongoing experimental program established to measure optical cross sections in the mid and long wave 

infrared for a variety of chemical and biologically based aerosols. For the present study we consider only chemically derived aerosols, and in 

particular, a group of chemical compounds often used as simulants for the detection of extremely toxic organophosphorus nerve agents. These 

materials include; diethyl methylphosphonate (DEMP), dimethyl methylphosphonate (DMMP), diisopropyl methylphosphonate (DIMP), and 

diethyl phthalate (DEP). As reported in a prior study, we combine two optical techniques well suited for aerosol spectroscopy (i.e., flow-through 

photoacoustics and FTIR emission spectroscopy), to measure in situ the absolute extinction and absorption cross sections over a variety of 

wavelengths spanning the IR spectral region from 3 to 13 μm. Aerosol size distribution(s), particle number density, and dosimetric measurements 

are recorded simultaneously in order to present optical cross sections that are aerosol mass normalized, i.e., m2/gram. Photoacoustic results 

conducted at a series of CO2 laser lines, compare well with measured broadband FTIR spectral extinction. Both FTIR and photoacoustic data also 

compare well with Mie theory calculations based on measured size distributions and previously published complex indices of refraction. 

15. SUBJECT TERMS

aerosol, cross-section, extinction, absorption, back-scatter, infrared, DEEP, DIMP, DMMP, DEP 

16. Security Classification of: 

19a. NAME OF RESPONSIBLE PERSON

Kristan P. Gurton 

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iii

Contents 

List of Figures iv

Acknowledgment vi

Introduction 1

Method 2

Results 7

Discussion 12

References 15

Appendix A. Complex Indices of Refraction for DIMP, DMMP, DEP (1, 2) 17

Appendix B. IR Absorptance Spectra for DMMP, DIMP, and DEMP 27

Distribution List 31 
iv

List of Figures 

Figure 1. Schematic of FTIR/photoacoustic experiment used to measure in situ the spectral 

extinction and absorption cross sections....................................................................................3 

Figure 2. Cross sectional schematic of a top set of acoustic dampeners used to isolate the 

electret inner cavity....................................................................................................................4 

Figure 3. Typical size distribution for the aerosolized chemical simulant. ....................................7 

Figure 4. Measured FTIR (solid line) and photoacoustic (data points) derived massnormalized extinction and absorption cross sections for DMMP. Also shown are the 

corresponding Mie theory calculations for the spectral extinction and absorption (dashed 

lines) based on the size distribution shown in figure 3 and previously published indices of 

refraction (11). ...........................................................................................................................9 

Figure 5. Measured mass-normalized FTIR spectral extinction (solid line) from 3 to 13 μm 

for DMMP. Also shown are the corresponding Mie theory calculations (dashed lines) for 

the spectral extinction, absorption, total scatter, and backscatter based on the size 

distribution shown in figure 3 and previously published indices of refraction (11)..................9 

Figure 6. Measured FTIR (solid line) and photoacoustic (data points) derived massnormalized extinction and absorption cross sections for DIMP. Also shown are the 

corresponding Mie theory calculations for the spectral extinction and absorption (dashed 

line) based on the size distribution shown in figure 3 and previously published indices of 

refraction (11). .........................................................................................................................10 

Figure 7. Measured mass-normalized FTIR spectral extinction (solid line) from 3 to 13 μm 

for DIMP. Also shown are the corresponding Mie theory calculations (dashed lines) for 

the spectral extinction, absorption, total scatter, and backscatter based on the size 

distribution shown in figure 3 and previously published indices of refraction (11)................10 

Figure 8. Measured FTIR (solid line) and photoacoustic (data points) derived mass 

normalized extinction and absorption cross sections for DEP. Also shown are the 

corresponding Mie theory calculations for the spectral extinction and absorption (dashed 

lines) based on the size distribution shown in figure 3 and previously published indices of 

refraction (11). .........................................................................................................................11 

Figure 9. Measured mass-normalized FTIR spectral extinction (solid line) from 3 to 13 μm 

for DEP. Also shown are the corresponding Mie theory calculations (dashed lines) for the 

spectral extinction, absorption, total scatter, and backscatter based on the size distribution 

shown in figure 3 and previously published indices of refraction (11). ..................................11 

Figure 10. Measured FTIR (solid line) and photoacoustic (data points) derived massnormalized extinction and absorption cross sections for DEMP. Representative size 

distribution 5 for the FTIR measurement can be seen in figure 2. Because no complex 

indices of refraction were available, no corresponding Mie theory calculations were 

conducted for DEMP. ..............................................................................................................12 

Figure 11. Various phase states for chemical agents during dispersion. ......................................13 

Figure B-1. Measured absorptance spectra for 1 cm path of liquid phase dimethylmethylphosphonate (DMMP). .................................................................................................27 
v

Figure B-2. Measured absorptance spectra for 1 cm path of liquid phase diisopropylmethylphosphonate (DIMP).....................................................................................................28

Figure B-3. Measured absorptance spectra for 1 cm path of liquid diethyl 

methylphosphonate (DEMP). ..................................................................................................29 
vi

Acknowledgment 

We would like to thank both the Air Force Research Laboratory (AFRL) and the Edgewood 

Chemical and Biological Command (ECBC) for their continued support and technical expertise. 
1

Introduction 

Currently there is great interest in developing new methods to safely detect the presences of 

airborne toxins. Light Detection and Ranging (LIDAR) systems have long been used to detect 

and map the presence of man-made and naturally occurring gas and aerosol concentrations in the 

open atmosphere (1, 2, 3). Recently Fourier transform infrared spectroscopy (FTIR) studies have 

identified unique spectral absorption/emission and backscatter characteristics for a variety of 

chemical and biological aerosols in the mid and long-wave IR (4, 5). However, the ability for 

such systems to take advantage of this spectral information will require multiple (or broadly 

tunable) laser sources that span a significant portion of the mid to long wave IR region of the 

spectrum. Current LIDAR systems designed for aerosol applications are usually limited to either 

near IR wavelengths (typically between 1 and 2 μm), or take advantage of the limited tunability 

between 9.2 and 10.8 μm associated with conventional CO2 lasers (3). However, with the advent 

of a relatively new class of solid state Quantum Cascade Lasers (QCL), coherent sources, with 

reasonable power and available for practically any wavelength between 3 and 17 μm, are 

becoming readily available (6, 7). 

As a result, new Chemical and Biological Warfare (CBW) agent “standoff” and “point” detection 

approaches and instrumentation are being considered, e.g., multi-wavelength or frequency agile 

LIDAR systems (8). In order to design and implement the various optically based detection 

methods being proposed, a reliable database of optical parameters is needed that encompass a 

variety of CBW related aerosols. Unfortunately, such information is lacking and is particularly 

sparce for biologically derived aerosols. 

In order to address this need, we have conducted a set of complimentary measurements that 

include conventional FTIR aerosol spectroscopy and flow-through photoacoustics designed to 

provide well calibrated optical cross sections in the IR wavelength region, 3 to 13 μm. This 

report represents a continuation of prior work in which mass normalized cross sections were 

measured and calculated for a variety of biological and inorganic particulates (9, 10). Although 

the experimental techniques used here are described in detail in prior reports, for completeness, 

we will briefly outline the methods and procedures used for both the broadband FTIR-based 

measurement and the single wavelength photoacoustic technique. 

In order to simultaneously measure the absolute extinction and absorption (and subsequently the 

total scatter via the difference) we employ two independent optical techniques which probe the 

same dispersed in situ aerosol volume, i.e., FTIR and flow-through photoacoustic aerosol 

spectroscopy. For the present study, we measure a path-integrated spectral extinction, ε(λ), from 

3 to 13 μm using an FTIR spectrometer that is operating in an emission mode, while the total 

absorption and extinction is measured using the photoacoustic technique at various single CO2
2

laser-line wavelengths between 9.2 and 10.8 μm, i.e., α(λ1), α(λ2), α(λ3), .... ε(λ1), ε(λ2), ε(λ3), 

etc. 

For chemical simulants in which the complex indices of refraction are available (11), Mie theory 

calculations are carried out over the same wavelength range by applying the indices with the 

measured aerosol size distribution. Finally, calculated total extinction, absorption, scatter, and 

backscatter cross sections are compared with values obtained from the FTIR/Photoacoustic 

portion of the experiment. 

Rather than working with the extremely toxic organophosphate derived “nerve” agents 

themselves, such as Soman (GD), or Sarin (GB), it is desirable to identify and work with more 

mundane “simulant” chemical compounds that exhibit similar molecular features. As a result a 

series of simulant materials have been identified that exhibit the same vibrational/rotational 

molecular behavior seen in the actual true toxins that are typically associated with Phosphorous 

Oxygen Carbon (POC) group(s). 

We chose four of the most commonly accepted nerve agent simulants for examination, i.e., 

dimethyl methylphosphonate (DMMP), diethyl methylphosphonate (DEMP), diisopropyl 

methylphosphonate (DIMP), and diethyl phthalate (DEP). These simulants posses the same P-O 

and P-C bonds seen in Sarin, Soman or V-series (VX) agents, yet lack the extremely reactive P-F 

bonds seen in actual nerve agents and are therefore considered much safer for laboratory 

analysis. 

Method 

Because the basic approach used for this study has been well documented elsewhere (4, 5, 9, 12), 

only a general description of the experimental and analytical techniques will be outlined here. 

The basic FTIR/photoacoustic aerosol measurement is shown in figure 1. 
3

Figure 1. Schematic of FTIR/photoacoustic experiment used to measure in situ the spectral extinction and 

absorption cross sections. 

As seen in figure 1, the system consists of a small aerosol chamber (approx. 0.4 m3

) where the 

chemical simulant is nebulized and uniformly dispersed using a low-velocity fan. A cylindrical 

flow-through photoacoustic “spectrophone” is mounted to the bottom of the chamber. Once 

dispersed, the aerosol is gently drawn down through a hollow region that runs axially through the 

device. A modulated CW CO2 laser, tuned to a specific IR wavelength, is directed through a 

BaF2 window located at the top of the chamber. The beam is directed down into the chamber 

and through the center of the spectrophone which contains the particle-air mixture. The beam 

exits through a windowless region located at the bottom of the spectrophone and attenuation of 

the laser power due to extinction by the aerosol is measured by a caloric IR detector located near 

the beam exit. Laser power is kept relatively low (typically less than 200 mW) to avoid phase 

changes associated with particle vaporization. At the center of the spectrophone cylinder is a 

small electret microphone that is embedded into the wall of the inner cavity. 

Ambient acoustic noise resulting from activity within the laboratory is suppressed by a series of 

acoustic dampeners located above and below the electret microphone (see figure 2). Figure 2 

Flow-through 

Photoacoustic Device 

for Absolute Absorption 

Measurement 

Aerodynamic Particle Sizing 

Probe (APS)

BOMEM Emission 

FTIR 

Broad 

Band 

Visible/IR 

Source 

Optical Detector 

for Absolute Extinction Measurement 

F/4 

Coupling

Optics 

Calibrated Flow-meter 

German Filter Sampling 

necessary for Dosimetric

t

Vacuum Pump

Chopper at 1kHz 

Tunable/discrete Coherent Light Source 

UV-Visible, Near-Mid and Far IR 

Pre-amp and 

Lock-in 

Amplifier

Aerosol

 Dispenser for liquids

Particle Capture

for 

SEM/Photography

AEROSOL 

BaF2 window w/ 

fresh air flush 
4

shows a cross sectional view of a top set of three cylindrical acoustic dampeners. These 

dampeners fit snuggly together in the region surrounding the inner electret cavity and serve to 

dissipate the acoustic noise which enters the spectrophone from either opening. Acoustic noise 

due to activities within the laboratory flow freely through the center cylindrical region of the 

spectrophone. Acoustic noise enters the spectrophone in the form of pressure fluctuations that 

are initially distributed over the area of the inlet nozzle shown as point A, in figure 2. For our 

example, define the area at point A to be 1.0 cm2. As the pressure-wave propagates down toward 

the inner electret cavity, it encounters several enlarged openings at point(s) B, in the figure. At 

these points the pressure wave is effectively redistributed over a much larger area, approximately 

5.0 cm2, resulting in a reduction of the net pressure. The attenuation of the noise signal is 

repeated at each slit B until the desired noise suppression is achieved. 

Figure 2. Cross sectional schematic of a top 

set of acoustic dampeners used to 

isolate the electret inner cavity. 

B

A

Aerosol

Flow in

Aerosol flow into the 

electret inner cavity 
5

We have found that a series of three or four dampeners placed above and below the electret 

cavity are sufficient to suppress typical noises levels encountered in the laboratory by 

approximately 20 dB at 1 kHz. Additionally, isolation is accomplished by machining the 

spectrophone enclosure from very dense materials, e.g., stainless steel or high density 

polyurethane. 

The basic principle behind aerosol photoacoustics is best explained by considering a simple 

example. Let us assume a sample volume containing an polydisperse distribution of optically 

absorbing aerosol particles. If a modulated laser is passed through this volume, the energy will 

be attenuated by a combination of particle scattering and absorption. The absorption results in a 

rapid heating and subsequent cooling of the particle-air mixture as the laser beam undergoes 

several duty cycles of the modulated laser (here we assume that the molecular absorption due to 

the surrounding gas is negligible compared to the resultant absorption by the particles). This 

cyclic heating/cooling of the aerosol mixture results in a pressure wave in the immediate region 

where the laser and aerosol interact. If the laser is modulated at some convenient acoustic 

frequency, 1 kHz for example, a resultant pressure wave will produce an acoustic signal at the 

same 1 kHz modulation frequency. The resultant acoustic signal can then be detected by the 

electret microphone. The electret produces an electrical signal, which is proportional to the 

absorbed energy and is amplified many orders of magnitude via a lock-in amplifier that is tuned 

to the 1 kHz frequency (13, 14). 

The responsivity and calibration of the photoacoustic device is achieved by designing the system 

such that the probe laser (in this case a tunable CO2 laser) also serves as a coincident short-pass 

transmissometer. Here the attenuating path of the transmissometer is defined from the top of the 

aerosol chamber, where the beam enters, and ends at a well defined point near the exit port 

where the aerosol is drawn from the system. By applying a simple Beer’s law relation, the 

arrangement allows for an independent measurement of the absolute path-integrated extinction 

coefficient, ε(1/m), that is used to calibrate the photoacoustic device. 

Calibration is carried out by substituting the aerosol with an absorbing gas. The calibration gas 

is drawn through the flow-through photoacoustic device in the exact same manner as the aerosol. 

However, now all of the extinction measured by the transmissometer results from absorption 

only of the calibration gas since there is no particulate scattering present (here we have assumed 

that molecular scattering is negligible when compared with the optical absorption). As with the 

aerosol, a rapid heating and cooling cycle occurs within the region near the electret. Again, an 

acoustic signal results and is detected and amplified, and is taken to be proportional to the optical 

absorption of the gas. 

Because there is no scattering during the calibration process, the total measured extinction (via 

the short-path transmissometer) is due solely to the absorption by the calibration gas. By 

equating the path-integrated extinction to the total absorption, we have ε(1/m) = α(1/m), where 
6

α(1/m) in now taken to be the path-integrated absorption. For each particular extinction 

coefficient, a corresponding acoustic signal is detected and recorded. The calibration process is 

repeated for different concentrations of gas and a plot of the spectrophone signal versus pathintegrated absorption (or extinction) is generated. The slope of this response curve represents a 

calibration constant relating aerosol absorption to spectrophone signal. Although any 

appropriately absorbing gas may be used to calibrate the device, we have found for operation in 

the LWIR that isopropanol alcohol vapor works well as an efficient absorbing gas for all CO2 

laser wavelengths considered. 

The broadband IR spectral extinction is measured using a high-resolution (0.02 wave-number) 

Bomem MR Series FTIR spectrometer. A radiometrically stabilized IR Nernst glow-bar is used 

as the broadband source. The broadband energy is collimated and projected through the aerosol 

chamber via two BaF2 transmission windows. All transmission windows are fitted with dry-air 

flushes to eliminate contamination due to aerosol build up. The broadband IR source is coupled 

to the FTIR spectrometer using a gold-surfaced, f/4, off-axis parabola. Because aerosol spectra 

are usually devoid of any sharp features (compared to spectra derived from gases), the 

spectrometer is operated at a moderate spectral resolution of 8 cm–1. 

The liquid chemical simulants are aerosolized within the chamber using a DeVilbiss 

pharmaceutical nebulizer. Approximately 20 psi of dry air is used to pump the nebulizer during 

dispersion. This results in a highly reproducible size distribution with particles predominately in 

the 6-μm range or less. Aerodynamic particle size distributions are measured continuously using 

an Aerodynamic Particle Sizer (APS), Model 3321, manufactured by TSI Inc. Particle 

aerodynamic derived diameters are converted to geometric diameters using the relation, 

d(aero) = d(geo) ρ Χ , where ρ is the bulk density of the simulant and Χ is an aerodynamic 

form factor which is taken to be 1 for perfect spheres. A typical size distribution resulting from 

the nebulizer is shown in figure 3. Note that once the aerosol chamber had reached equilibrium, 

i.e., number of particles being generated by the nebulizer equals number of particles being lost 

due to impacting with the chamber walls and/or fan, the size distributions remained exceptionally 

stable during the entire run. Similarly, because each of the four chemicals had very nearly 

identical viscosities and vapor pressures, and because great care was taken to ensure nebulizer 

pressure remained constant between measurements, the distribution seen in the figure 3 is a 

reasonable representation for all simulants considered and for all measurements conducted. 
7

1

10

100

1000

10000

100000

0.1 1 10 100

Particle Diameter (um) 

Particle 

count 

(10 sec)

Figure 3. Typical size distribution for the aerosolized chemical simulant. 

Aerosol mass densities (g/m3) are periodically measured during each run using conventional 

dosimetric techniques. Aerosol mass samples are continuously collected during the 

photoacoustic/FTIR measurements by drawing known volumes of the air-particle mixture onto 

polycarbonate filters (nominal pore-size 0.20 μm), for predetermined periods of time. Mass 

samples are then weighed and used to convert path-integrated extinction and absorption cross 

sections (1/m), into the more useful mass normalized quantities (m2

/g). 

Results 

The four nerve agent simulants considered for this study include dimethyl methylphosphonate 

(DMMP) CAS#756-79-6 (simulant for Sarin), diethyl phosphonate (DEMP) CAS#683-08-9 

(simulant for Sarin), both purchased from Fluka Inc., diisopropyl phosphonate (DIMP) 

CAS#1445-75-6 (simulant for Soman), which was purchased from Lancaster Synthesis, Inc., and 

diethyl phthalate (DEP) CAS#84-66-2 (simulant for V-series VX nerve agents), purchased from 

Sigma-Aldrich, Inc. All four liquid chemicals possess no noticeable color or odor and all exhibit 

relatively low vapor pressure. 
8

In order to avoid confusion, the spectra from each simulant is displayed in two graphs. The first 

graph displays the laser-line measurements of the photoacoustic study from 9 to 11 μm, and the 

corresponding broad band spectral extinction obtained from the FTIR and corresponding Mie 

theory calculations. The second graph displays an expanded view (range from 3 to 13 μm) of the 

broad band spectral extinction, absorption, total scatter, and the differential backscatter, obtained 

from the FTIR work and Mie theory calculations. Unfortunately, Mie theory calculations could 

not be conducted for DEMP shown in figure 10 because complex indices of refraction for this 

material were not available. For all transmission type measurements, i.e., both FTIR and CO2

laser line extinction, a forward scatter correction is applied (15). In all cases this correction is 

relatively small beyond 7 to 8 μm. Note that for all simulants considered here, the complex 

portion of the index of refraction, which is directly related to the optical absorption, was 

extremely small-in the approximate region 3.5 to 6.5 μm. As a result, the spurious behavior of 

Mie calculated absorption for this region, as seen in figures 5, 7, 9, is effectively taken to be 

zero. As shown in figures 4 through 10, results of the FTIR and photoacoustic measurements 

agree reasonably well with the Mie calculated values with the exception the DEP spectra shown 

in figure 8. Here one can see a divergence between measured and Mie calculated absorption 

between 10 and 11 μm. Although the overall trend downwards appear similar, the magnitudes of 

the values differ greatly. After thorough review we believe the discrepancy arises from the fact 

that the absorption values beyond 10 μm are relatively small. As a result, large uncertainties 

exist for both the measured photoacoustic results and in the methods used by Querry to 

determine the complex indices of refraction used in the Mie calculations (11). At such low 

levels of absorption, small uncertainties in the values of the complex portion of the index result 

in large variation in the Mie calculated values of the absorption. After review we attribute the 

disagreement between measured and calculated absorption for the last two data points seen in 

figure 8, to a low signal-to-noise region inherent in both studies and thus not entirely unexpected. 

For completeness we have included in appendix A the tabular values of the complex refractive 

indices taken from Querry (11). 
9

DMMP 

DMMP dimethyl methylphosphonate

1.E-04

1.E-03

1.E-02

1.E-01

9 10 11

Wavelength (um)

Cross 

Section 

(m2

/gr)

Mie Extinction

Mie Absorption 

FTIR Extinction

Photo Absorption

Photo Ext

Figure 4. Measured FTIR (solid line) and photoacoustic (data points) derived mass-normalized extinction 

and absorption cross sections for DMMP. Also shown are the corresponding Mie theory 

calculations for the spectral extinction and absorption (dashed lines) based on the size distribution 

shown in figure 3 and previously published indices of refraction (11). 

DMMP dimethyl methylphosphonate

1.E-04

1.E-03

1.E-02

1.E-01

3 5 7 9 11 13

Wavelength (um)

Cross 

Section 

(m2

/gr) Mie Extinction

Mie Scattering

Mie Absorption 

Mie Backscatter 

FTIR Extinction

Figure 5. Measured mass-normalized FTIR spectral extinction (solid line) from 3 to 13 μm for DMMP. Also 

shown are the corresponding Mie theory calculations (dashed lines) for the spectral extinction, 

absorption, total scatter, and backscatter based on the size distribution shown in figure 3 and 

previously published indices of refraction (11). 
10

DIMP 

DIMP diisopropyl phosphonate

1.E-04

1.E-03

1.E-02

1.E-01

9 10 11

Wavelength (um)

Cross 

Section 

(m2

/gr)

Photo Extinction 

Photo Absorption 

FTIR Extinction 

Mie Extinction 

Mie Absorption

Figure 6. Measured FTIR (solid line) and photoacoustic (data points) derived mass-normalized extinction and 

absorption cross sections for DIMP. Also shown are the corresponding Mie theory calculations for the 

spectral extinction and absorption (dashed line) based on the size distribution shown in figure 3 and 

previously published indices of refraction (11). 

DIMP diisopropyl phosphonate

1.E-04

1.E-03

1.E-02

1.E-01

3 5 7 9 11 13

Wavelength (um)

Cross 

Section 

(m2

/gr)

FTIR Extinction 

Mie Extinction 

Mie Scattering 

Mie Absorption

Mie Backscatter

Figure 7. Measured mass-normalized FTIR spectral extinction (solid line) from 3 to 13 μm for DIMP. Also 

shown are the corresponding Mie theory calculations (dashed lines) for the spectral extinction, 

absorption, total scatter, and backscatter based on the size distribution shown in figure 3 and 

previously published indices of refraction (11). 
11

DEP

DEP diethyl phthalate

1.E-04

1.E-03

1.E-02

1.E-01

9 10 11

Wavelength (um)

CrossSection 

(m2

/gr) FTIR Extinction

Mie Extinction

Mie Absorption

absorption (m2/gr)

extinction (m2/gr)

Figure 8. Measured FTIR (solid line) and photoacoustic (data points) derived mass 

normalized extinction and absorption cross sections for DEP. Also shown 

are the corresponding Mie theory calculations for the spectral extinction 

and absorption (dashed lines) based on the size distribution shown in 

figure 3 and previously published indices of refraction (11). 

 

DEP diethyl phthalate

1.E-03

1.E-02

1.E-01

1.E+00

3 4 5 6 7 8 9 10 11 12 13

Wavelength (um)

CrossSection 

(m2

/gr)

FTIR Extinction

Mie Extinction

Mie Scattering

Mie Absorption

Mie Backscatter

Figure 9. Measured mass-normalized FTIR spectral extinction (solid line) from 3 to 

13 μm for DEP. Also shown are the corresponding Mie theory calculations 

(dashed lines) for the spectral extinction, absorption, total scatter, and 

backscatter based on the size distribution shown in figure 3 and previously 

published indices of refraction (11).
12

DEMP 

DEMP diethyl phosphonate 

1.E-03

1.E-02

1.E-01

1.E+00

3 4 5 6 7 8 9 10 11 12 13

Wavelength (um)

Cross 

Section 

(m2

/gr)

Photo Extinction 

FTIR Extinction

Photo Absorption

Figure 10. Measured FTIR (solid line) and photoacoustic (data points) derived massnormalized extinction and absorption cross sections for DEMP. Representative 

size distribution 5 for the FTIR measurement can be seen in figure 2. Because 

no complex indices of refraction were available, no corresponding Mie theory 

calculations were conducted for DEMP. 

Discussion 

At this point it is useful to discuss the effect of phase state of the chemical agent and/or particle 

size distributions on various optical properties in the IR. So far we have focused on four specific 

chemical agents, and in particular, in aerosol form. However, from the standpoint of detection of 

a particular agent, the phase of the material is just as important of a factor as chemical 

composition. Depending on how the agent is dispersed, the phase state of chemical may include 

vapor, liquid, thickened liquid (which may produce vapor also), small and large sized aerosol 

particles, and rain-sized droplets. A schematic showing a possible scenario in which all phase 

states are present is shown in figure 11. 
13

Figure 11. Various phase states for chemical agents during dispersion. 

Flanigan has reported only minor differences between liquid and vapor phase for measured IR 

absorption spectra for a variety of chemical agents (16, 17). At first glance one might find this 

peculiar, since it is well known that IR spectra of diatomic and simple polyatomic vapor 

molecules generally exhibit significantly more fine line structure when compared to spectra 

derived from liquids. However, for complex molecular compounds like the simulants considered 

here, the spacing between lines become reduced, and for asymmetric molecules the position of 

these lines become quite random. The net effect is that the spectral lines appear to overlay one 

another and are rarely able to be resolved with conventional spectroscopy. It is for this reason 

that the vapor/gaseous spectrum for most chemical agents (which tend to be highly asymmetric) 

lack the fine line structure often observed in other gaseous media. 

For aerosols and/or droplets, scattering becomes an important component to the total extinction 

and factors such as particle size and shape become important. This is particularly true as the 

predominate particle size become comparable to the wavelength. As a result, a small variation in 

the particle side distribution can have dramatic effects on the various spectral components. 

Therefore, when designing aerosol detection systems which relies on cues from a particular 

absorption, extinction, or backscatter feature, reasonable accuracy of the expected sized 

distribution is usually required. 

It should be obvious that, based on the previous few paragraphs, one should be careful when 

designing systems to exploit a particular spectral feature, to ensure the measured phase state 

matches that of the anticipate application. For example, one might consider absorption spectra 

derived from vapor or liquid, if the application is to detect CBW surface contamination. 

However, the use of the same spectra for developing an aerosol detection scheme would not be 

appropriate. Unfortunately, this mistake is more common than one might expect. Errors 

resulting from phase state mismatch is most common for application dealing with obscure 

materials in which good extinction or absorption spectra (for a particular phase) does not exist 

wind 

initial dispersion 

primary vapor 

large drops and 

aerosol 

liquid 

vapor from falling drops 

and aerosol 

secondary vapor 
14

and spectra derived from a different state is knowingly (or unknowingly) applied. This is 

particularly true for biological materials where the existing measured IR spectra is still quite 

sparse (18, 19, 20). 

For completeness and comparison with measured aerosol spectra seen in figures 4 through 10, 

we show the absorptance spectra measured for liquid DEMP, DMMP, and DIMP simulants (see 

appendix B (11, 21)). Unfortunately, due to a technical problem that arose with the FTIR 

spectrometer, we were unable to measure the absorptance spectra for the chemical simulant DEP 

and thus it is not shown. 

Finally, a few general comments on how the various spectral features seen in figures 4 through 

10 are effected by differing size distributions. In order to proceed, let us define three different 

distributions based on the nominal size of the particles, when compared to mid or long wave IR 

wavelengths. For such a wavelength region we define three aerosols distributions as small 

(nominal particle dia. < 2 μm), intermediate (nominal particle dia. between 2 to 30 μm), and 

large or droplet size (particle dia. > 30 μm). For the current study we intentionally generated 

particles with sizes that lie within the “intermediate” range since it is considered the most 

probable scenario that one might expect in practice. 

If the expected particle sizes tend towards a “small” distribution, the contribution due to 

scattering will be greatly reduced and spectral features for both extinction and absorption (or 

emission for the IR) will dominate. As a result, the differences between peaks and valleys of the 

spectra, seen in figures 4 through 10 for those components, will increase and look very similar to 

the type of spectrum derived for a vapor phase. 

For size distributions that tend towards the “large” size (but still not characterized as droplets, 

e.g., 10 to 30 μm range), particle scattering increases rapidly and the spectral features seen in 

figures 4 through 10 will become less prominent for the extinction and absorption with the 

absorption (and emission) retaining spectral features a bit longer than that of the extinction. 

Also, as the particle sizes increase, the expected backscatter spectra will shift slowly towards the 

longer wavelengths. 

For particles that are best characterized as “droplets” (30 to 100 μm) detection schemes based on 

the identification of certain spectral features are considered to be useless since the resultant 

spectra for these sized particles are nearly flat. However, there still exists reasonable backscatter 

structure that remains relatively constant although slightly shifted towards longer wavelengths. 

As result, a multi-spectral IR LIDAR detection approach seems reasonable since the expected 

backscatter response would be relatively predictable over a wide range of particle sizes. This 

approach could be strengthened/complimented by including a “passive” muti-spectral IR 

imaging approach since absorption/emission spectral features hold up fairly well (particularly in 

the LWIR region) over a similar range of particle size distributions. 
15

References 

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wavelengths: implications of aerosol spectral structure on differential-absorption LIDAR 

retrievals of molecular species. Appl. Opt. 1999, 38 (12), 2616–2624. 

2. Koch, Grady J.; Barnes, Bruce W.; Petros, Mulugeta; Beyon, Jeffrey Y. Coherent 

Differential Absorption Lidar Measurements of CO2. Appl. Opt. 2004, 43 (26), 5092–5099.

3. Vanderbeek, R.; Gurton, K. Backscatter Measurements of Aerosolized CB Simulants with a 

Frequency Agile CO2 Lidar. SPIE International Symposium Photonics East, Providence, 

Rhode Island USA, October 27–30, 2003.

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chemical and biological aerosol simulants. Appl. Opt. 2004, 43 (23), 4564–4570.

5. Gurton, Kristan P.; Ligon, David; Kvavilashvili, Ramaz. Measured Infrared Spectral 

Extinction for Aerosolized Bacillus subtilis var. niger endospores from 3 to 13 μm. Applied 

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spectral extinction for various chemical, biological, and background aerosols; ARL-TR3071; U.S. Army Research Laboratory: Adelphi, MD, September 2003. 

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CRDEC-CR88009, November 1987. 
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12. Gurton, K. P.; Dahmani, R.; Ligon, D.; Bronk, B. Measured IR absorption and extinction 

cross sections for a variety of chemically and biologically derived aerosol simulants; ARLTR-3253; U.S. Army Research Laboratory: Adelphi, MD, June 2004. 

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York, 1980. 

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aerosol media. 2: Polydispersion. Appl. Opt. 1978, 17 (19), 3169–3176. 

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Chemical Research and Development Center Technical Report # CRDC-TR-85002: April 

1985. 

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York, 1996. 

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of Liquids and Solids at Carbon Dioxide Laser Wavelengths in the Infrared Spectral Region, 

U.S. Army Chemical Research, Development & Engineering Center; Technical Report, 

Report # CRDEC-CR-062, Jan. 1990. 
17

Appendix A. Complex Indices of Refraction for DIMP, DMMP, DEP (1, 2) 

DIMP DMMP DEP 

λ (μm) n k λ (μm) n k λ (μm) n k 

55.56 1.44 0.0000 55.56 1.50 0.0440 55.56 1.50 0.0000 

52.63 1.45 0.0000 52.63 1.53 0.0450 52.63 1.51 0.0000 

50.00 1.45 0.0000 50.00 1.51 0.0950 50.00 1.52 0.0000 

47.62 1.46 0.0000 47.62 1.47 0.1020 47.62 1.52 0.0000 

45.45 1.45 0.0000 45.45 1.46 0.0940 45.45 1.53 0.0000 

43.48 1.46 0.0000 43.48 1.44 0.0750 43.48 1.53 0.0000 

41.67 1.47 0.0000 41.67 1.43 0.0470 41.67 1.52 0.0000 

40.00 1.48 0.0110 40.00 1.43 0.0330 40.00 1.53 0.0000 

38.46 1.47 0.0240 38.46 1.45 0.0190 38.46 1.53 0.0000 

37.04 1.46 0.0260 37.04 1.46 0.0140 37.04 1.53 0.0030 

35.71 1.45 0.0240 35.71 1.48 0.0160 35.71 1.53 0.0050 

34.48 1.44 0.0160 34.48 1.50 0.0280 34.48 1.53 0.0060 

33.33 1.45 0.0080 33.33 1.50 0.0620 33.33 1.53 0.0120 

32.26 1.45 0.0080 32.26 1.46 0.0860 32.26 1.53 0.0170 

31.25 1.45 0.0060 31.25 1.42 0.0440 31.25 1.53 0.0230 

30.30 1.45 0.0050 30.30 1.44 0.0170 30.30 1.53 0.0320 

29.41 1.46 0.0010 29.41 1.46 0.0070 29.41 1.52 0.0400 

28.57 1.47 0.0050 28.57 1.47 0.0040 28.57 1.51 0.0430 

27.78 1.47 0.0050 27.78 1.48 0.0020 27.78 1.49 0.0350 

27.03 1.48 0.0150 27.03 1.50 0.0060 27.03 1.50 0.0230 

26.32 1.48 0.0240 26.32 1.52 0.0160 26.32 1.50 0.0160 

25.64 1.47 0.0280 25.64 1.55 0.0490 25.64 1.51 0.0210 

25.00 1.47 0.0310 25.00 1.53 0.1110 25.00 1.50 0.0280 

24.39 1.47 0.0390 24.39 1.52 0.1260 24.39 1.49 0.0240 

23.81 1.47 0.0450 23.81 1.39 0.1090 23.81 1.49 0.0110 

23.26 1.45 0.0430 23.26 1.44 0.0350 23.26 1.49 0.0030 

22.73 1.45 0.0330 22.73 1.47 0.0340 22.73 1.50 0.0030 

22.22 1.46 0.0280 22.22 1.48 0.0530 22.22 1.50 0.0040 

21.74 1.47 0.0260 21.74 1.80 0.0750 21.74 1.50 0.0020 

21.28 1.48 0.0280 21.28 1.46 0.0990 21.28 1.51 0.0020 

20.83 1.49 0.0440 20.83 1.46 0.0610 20.83 1.51 0.0000 

20.41 1.50 0.0640 20.41 1.52 0.0740 20.41 1.51 0.0000 

20.00 1.51 0.1470 20.00 1.46 0.2690 20.00 1.51 0.0000 

19.61 1.39 0.1470 19.61 1.29 0.1050 19.61 1.51 0.0000 

19.23 1.35 0.1000 19.23 1.35 0.0120 19.23 1.52 0.0030 

18.87 1.36 0.0320 18.87 1.38 0.0070 18.87 1.52 0.0030 

18.52 1.39 0.0180 18.52 1.41 0.0030 18.52 1.52 0.0030 

18.18 1.40 0.0180 18.18 1.42 0.0020 18.18 1.52 0.0050 

17.86 1.40 0.0140 17.86 1.43 0.0000 17.86 1.52 0.0240 

17.54 1.41 0.0040 17.54 1.44 0.0000 17.54 1.50 0.0070 

17.24 1.42 0.0040 17.24 1.45 0.0000 17.24 1.51 0.0000 

16.95 1.42 0.0000 16.95 1.45 0.0000 16.95 1.52 0.0000 

16.67 1.43 0.0000 16.67 1.46 0.0040 16.67 1.53 0.0000 

16.39 1.44 0.0000 16.39 1.46 0.0040 16.39 1.53 0.0000 

16.13 1.44 0.0000 16.13 1.48 0.0060 16.13 1.53 0.0010 
18

15.87 1.44 0.0000 15.87 1.48 0.0060 15.87 1.53 0.0030 

15.63 1.45 0.0020 15.63 1.48 0.0070 15.63 1.54 0.0030 

15.38 1.45 0.0030 15.38 1.49 0.0050 15.38 1.54 0.0230 

15.15 1.45 0.0000 15.15 1.49 0.0050 15.15 1.53 0.0020 

14.93 1.46 0.0000 14.93 1.51 0.0090 14.93 1.54 0.0000 

14.71 1.47 0.0020 14.71 1.51 0.0120 14.71 1.55 0.0010 

14.49 1.47 0.0020 14.49 1.52 0.0140 14.49 1.57 0.0230 

14.29 1.48 0.0090 14.29 1.54 0.0300 14.29 1.57 0.0420 

14.08 1.50 0.0220 14.08 1.55 0.1050 14.08 1.53 0.0410 

13.89 1.46 0.0600 13.89 1.46 0.0390 13.89 1.56 0.0170 

13.70 1.45 0.0130 13.70 1.50 0.0120 13.70 1.60 0.0330 

13.51 1.48 0.0150 13.51 1.52 0.0120 13.51 1.62 0.1550 

13.33 1.48 0.0320 13.33 1.55 0.0150 13.33 1.44 0.1570 

13.16 1.48 0.0140 13.16 1.58 0.0160 13.16 1.45 0.0590 

12.99 1.50 0.0150 12.99 1.62 0.0370 12.99 1.47 0.0430 

12.82 1.54 0.0340 12.82 1.71 0.1340 12.82 1.48 0.0450 

12.66 1.50 0.1500 12.66 1.48 0.2940 12.66 1.47 0.0380 

12.50 1.40 0.0680 12.50 1.48 0.0980 12.50 1.47 0.0200 

12.35 1.43 0.0160 12.35 1.65 0.1610 12.35 1.48 0.0030 

12.20 1.46 0.0090 12.20 1.40 0.4350 12.20 1.49 0.0030 

12.05 1.47 0.0070 12.05 1.25 0.1220 12.05 1.51 0.0010 

11.90 1.49 0.0040 11.90 1.37 0.0340 11.90 1.52 0.0070 

11.76 1.50 0.0090 11.76 1.43 0.0210 11.76 1.52 0.0160 

11.63 1.52 0.0090 11.63 1.47 0.0240 11.63 1.51 0.0310 

11.49 1.54 0.0170 11.49 1.52 0.0240 11.49 1.49 0.0280 

11.36 1.56 0.0290 11.36 1.56 0.0440 11.36 1.50 0.0050 

11.24 1.59 0.0510 11.24 1.62 0.1300 11.24 1.51 0.0060 

11.11 1.56 0.1190 11.11 1.57 0.2100 11.11 1.51 0.0010 

10.99 1.57 0.1000 10.99 1.52 0.3170 10.99 1.52 0.0000 

10.87 1.50 0.1240 10.87 1.30 0.2650 10.87 1.52 0.0000 

10.75 1.54 0.0520 10.75 1.31 0.0820 10.75 1.53 0.0000 

10.64 1.59 0.0500 10.64 1.39 0.0310 10.64 1.53 0.0000 

10.53 1.66 0.0630 10.53 1.43 0.0220 10.53 1.54 0.0000 

10.42 1.75 0.1040 10.42 1.48 0.0210 10.42 1.55 0.0050 

10.31 1.93 0.2670 10.31 1.52 0.0230 10.31 1.55 0.0020 

10.20 1.80 0.7420 10.20 1.56 0.0300 10.20 1.56 0.0020 

10.10 1.33 0.7210 10.10 1.62 0.0420 10.10 1.58 0.0040 

10.00 1.23 0.4890 10.00 1.70 0.0660 10.00 1.60 0.0190 

9.90 1.20 0.5420 9.90 1.82 0.1440 9.90 1.60 0.0570 

9.80 0.97 0.3800 9.80 1.95 0.4210 9.80 1.55 0.0700 

9.71 1.02 0.1440 9.71 1.66 0.8130 9.71 1.57 0.0240 

9.62 1.12 0.0640 9.62 1.25 0.6730 9.62 1.58 0.1030 

9.52 1.19 0.0390 9.52 1.25 0.4930 9.52 1.57 0.0210 

9.43 1.23 0.0250 9.43 1.14 0.5730 9.43 1.65 0.0360 

9.35 1.27 0.0190 9.35 0.91 0.3570 9.35 1.66 0.2190 

9.26 1.30 0.0190 9.26 1.01 0.1190 9.26 1.44 0.1290 

9.17 1.34 0.0240 9.17 1.10 0.0610 9.17 1.54 0.0530 

9.09 1.39 0.0570 9.09 1.17 0.0350 9.09 1.58 0.0620 

9.01 1.33 0.1430 9.01 1.22 0.0310 9.01 1.63 0.1300 

8.93 1.29 0.0610 8.93 1.25 0.0200 8.93 1.58 0.2280 

8.85 1.32 0.0450 8.85 1.28 0.0190 8.85 1.48 0.2310 

8.77 1.34 0.0830 8.77 1.30 0.0240 8.77 1.38 0.1850 

8.70 1.31 0.0410 8.70 1.33 0.0180 8.70 1.39 0.0670 
19

8.62 1.34 0.0360 8.62 1.36 0.0350 8.62 1.45 0.0400 

8.55 1.36 0.0460 8.55 1.39 0.0500 8.55 1.48 0.0590 

8.47 1.33 0.0740 8.47 1.38 0.0950 8.47 1.46 0.0340 

8.40 1.34 0.0330 8.40 1.34 0.0950 8.40 1.49 0.0180 

8.33 1.36 0.0280 8.33 1.35 0.0450 8.33 1.52 0.0150 

8.26 1.39 0.0330 8.26 1.39 0.0400 8.26 1.54 0.0130 

8.20 1.41 0.0350 8.20 1.46 0.0430 8.20 1.58 0.0180 

8.13 1.47 0.0690 8.13 1.56 0.1040 8.13 1.61 0.0280 

8.06 1.50 0.2450 8.06 1.59 0.3610 8.06 1.68 0.0740 

8.00 1.23 0.2660 8.00 1.30 0.4440 8.00 1.70 0.1390 

7.94 1.22 0.1170 7.94 1.12 0.3800 7.94 1.70 0.2350 

7.87 1.23 0.0630 7.87 1.04 0.1300 7.87 1.70 0.3450 

7.81 1.27 0.0340 7.81 1.15 0.0320 7.81 1.55 0.5030 

7.75 1.30 0.0210 7.75 1.22 0.0250 7.75 1.30 0.5200 

7.69 1.33 0.0220 7.69 1.28 0.0280 7.69 1.12 0.3270 

7.63 1.33 0.0860 7.63 1.31 0.1310 7.63 1.15 0.1060 

7.58 1.27 0.0320 7.58 1.19 0.0970 7.58 1.25 0.0420 

7.52 1.31 0.0090 7.52 1.20 0.0190 7.52 1.31 0.0170 

7.46 1.33 0.0150 7.46 1.24 0.0050 7.46 1.35 0.0150 

7.41 1.34 0.0220 7.41 1.26 0.0000 7.41 1.36 0.0100 

7.35 1.35 0.0210 7.35 1.28 0.0100 7.35 1.43 0.0340 

7.30 1.38 0.0550 7.30 1.29 0.0010 7.30 1.34 0.0890 

7.25 1.33 0.0700 7.25 1.30 0.0030 7.25 1.38 0.0230 

7.19 1.27 0.0550 7.19 1.31 0.0080 7.19 1.39 0.0380 

7.14 1.30 0.0130 7.14 1.31 0.0000 7.14 1.39 0.0200 

7.09 1.32 0.0100 7.09 1.33 0.0080 7.09 1.40 0.0090 

7.04 1.32 0.0150 7.04 1.32 0.0260 7.04 1.41 0.0080 

6.99 1.32 0.0120 6.99 1.32 0.0170 6.99 1.43 0.0090 

6.94 1.34 0.0120 6.94 1.33 0.0190 6.94 1.45 0.0270 

6.90 1.34 0.0190 6.90 1.33 0.0280 6.90 1.42 0.0460 

6.85 1.34 0.0230 6.85 1.32 0.0360 6.85 1.43 0.0270 

6.80 1.32 0.0260 6.80 1.31 0.0330 6.80 1.42 0.0340 

6.76 1.32 0.0040 6.76 1.31 0.0230 6.76 1.41 0.0260 

6.71 1.33 0.0050 6.71 1.31 0.0130 6.71 1.41 0.0230 

6.67 1.33 0.0050 6.67 1.31 0.0080 6.67 1.42 0.0010 

6.62 1.33 0.0010 6.62 1.32 0.0050 6.62 1.43 0.0060 

6.58 1.34 0.0020 6.58 1.32 0.0030 6.58 1.44 0.0020 

6.54 1.34 0.0020 6.54 1.33 0.0020 6.54 1.44 0.0050 

6.49 1.34 0.0020 6.49 1.33 0.0000 6.49 1.45 0.0040 

6.45 1.34 0.0020 6.45 1.33 0.0010 6.45 1.45 0.0010 

6.41 1.35 0.0000 6.41 1.34 0.0020 6.41 1.45 0.0050 

6.37 1.35 0.0000 6.37 1.34 0.0030 6.37 1.47 0.0060 

6.33 1.35 0.0000 6.33 1.34 0.0010 6.33 1.46 0.0260 

6.29 1.35 0.0010 6.29 1.34 0.0000 6.29 1.47 0.0080 

6.25 1.35 0.0010 6.25 1.34 0.0000 6.25 1.46 0.0280 

6.21 1.35 0.0010 6.21 1.34 0.0010 6.21 1.46 0.0060 

6.17 1.36 0.0010 6.17 1.34 0.0010 6.17 1.47 0.0040 

6.13 1.36 0.0000 6.13 1.35 0.0010 6.14 1.48 0.0040 

6.10 1.36 0.0010 6.10 1.35 0.0010 6.10 1.48 0.0030 

6.06 1.36 0.0020 6.06 1.35 0.0010 6.06 1.49 0.0060 

6.02 1.36 0.0030 6.02 1.35 0.0000 6.02 1.50 0.0050 

5.99 1.36 0.0030 5.99 1.35 0.0000 5.99 1.52 0.0090 

5.95 1.36 0.0020 5.95 1.35 0.0000 5.95 1.53 0.0150 
20

5.92 1.36 0.0030 5.92 1.35 0.0000 5.92 1.56 0.0240 

5.88 1.36 0.0040 5.88 1.36 0.0000 5.88 1.50 0.0350 

5.85 1.36 0.0050 5.85 1.36 0.0000 5.85 1.64 0.1060 

5.81 1.36 0.0040 5.81 1.36 0.0000 5.81 1.65 0.3460 

5.78 1.36 0.0030 5.78 1.36 0.0010 5.78 1.39 0.4340 

5.75 1.36 0.0010 5.75 1.36 0.0010 5.75 1.19 0.2600 

5.71 1.36 0.0020 5.71 1.36 0.0020 5.71 1.22 0.0140 

5.68 1.36 0.0040 5.68 1.36 0.0010 5.68 1.30 0.0280 

5.65 1.36 0.0040 5.65 1.36 0.0000 5.65 1.34 0.0170 

5.62 1.36 0.0010 5.62 1.36 0.0000 5.62 1.36 0.0090 

5.59 1.36 0.0000 5.59 1.36 0.0000 5.59 1.37 0.0050 

5.56 1.37 0.0000 5.56 1.36 0.0000 5.56 1.39 0.0020 

5.52 1.37 0.0010 5.52 1.36 0.0010 5.52 1.39 0.0050 

5.49 1.37 0.0010 5.49 1.36 0.0020 5.49 1.40 0.0040 

5.46 1.37 0.0010 5.46 1.36 0.0020 5.46 1.41 0.0020 

5.43 1.37 0.0000 5.43 1.37 0.0020 5.43 1.41 0.0030 

5.41 1.37 0.0010 5.41 1.37 0.0030 5.41 1.41 0.0060 

5.38 1.37 0.0010 5.38 1.36 0.0040 5.38 1.42 0.0030 

5.35 1.37 0.0010 5.35 1.36 0.0030 5.35 1.42 0.0040 

5.32 1.37 0.0010 5.32 1.36 0.0030 5.32 1.42 0.0030 

5.29 1.37 0.0010 5.29 1.36 0.0010 5.29 1.43 0.0020 

5.26 1.37 0.0020 5.26 1.36 0.0000 5.26 1.43 0.0030 

5.24 1.37 0.0010 5.24 1.37 0.0000 5.24 1.43 0.0030 

5.21 1.37 0.0010 5.21 1.37 0.0010 5.21 1.43 0.0020 

5.18 1.37 0.0010 5.18 1.37 0.0020 5.18 1.43 0.0030 

5.15 1.37 0.0020 5.15 1.38 0.0010 5.15 1.43 0.0030 

5.13 1.37 0.0030 5.13 1.39 0.0010 5.13 1.44 0.0030 

5.10 1.37 0.0030 5.10 1.37 0.0030 5.10 1.44 0.0030 

5.08 1.37 0.0020 5.08 1.37 0.0040 5.08 1.44 0.0040 

5.05 1.37 0.0030 5.05 1.37 0.0030 5.05 1.44 0.0060 

5.03 1.37 0.0040 5.03 1.37 0.0030 5.03 1.44 0.0070 

5.00 1.37 0.0050 5.00 1.37 0.0050 5.00 1.44 0.0060 

4.98 1.37 0.0030 4.98 1.37 0.0060 4.98 1.44 0.0040 

4.95 1.37 0.0020 4.95 1.37 0.0040 4.95 1.44 0.0030 

4.93 1.37 0.0010 4.93 1.37 0.0020 4.93 1.44 0.0030 

4.90 1.37 0.0010 4.90 1.37 0.0020 4.90 1.44 0.0030 

4.88 1.37 0.0010 4.88 1.37 0.0020 4.88 1.44 0.0030 

4.85 1.37 0.0030 4.85 1.37 0.0020 4.85 1.44 0.0020 

4.83 1.37 0.0030 4.83 1.37 0.0010 4.83 1.44 0.0000 

4.81 1.37 0.0030 4.81 1.37 0.0010 4.81 1.44 0.0000 

4.78 1.37 0.0020 4.78 1.37 0.0000 4.78 1.44 0.0010 

4.76 1.37 0.0030 4.76 1.37 0.0000 4.76 1.44 0.0020 

4.74 1.37 0.0030 4.74 1.37 0.0000 4.74 1.44 0.0020 

4.72 1.37 0.0020 4.72 1.37 0.0000 4.72 1.44 0.0020 

4.69 1.37 0.0000 4.69 1.37 0.0000 4.69 1.45 0.0010 

4.67 1.37 0.0000 4.67 1.37 0.0000 4.67 1.45 0.0010 

4.65 1.37 0.0000 4.65 1.37 0.0000 4.65 1.45 0.0010 

4.63 1.37 0.0000 4.63 1.37 0.0000 4.63 1.45 0.0000 

4.61 1.37 0.0000 4.61 1.37 0.0010 4.61 1.45 0.0000 

4.59 1.38 0.0000 4.59 1.37 0.0000 4.59 1.45 0.0000 

4.57 1.38 0.0000 4.57 1.37 0.0000 4.57 1.45 0.0010 

4.55 1.38 0.0000 4.55 1.37 0.0000 4.55 1.45 0.0000 

4.52 1.38 0.0010 4.52 1.37 0.0000 4.52 1.45 0.0000 
21

4.50 1.38 0.0020 4.50 1.37 0.0000 4.50 1.45 0.0000 

4.48 1.38 0.0020 4.48 1.38 0.0000 4.48 1.45 0.0010 

4.46 1.38 0.0000 4.46 1.38 0.0000 4.46 1.45 0.0010 

4.44 1.38 0.0000 4.44 1.38 0.0000 4.44 1.45 0.0000 

4.42 1.38 0.0010 4.42 1.38 0.0010 4.42 1.45 0.0000 

4.41 1.38 0.0020 4.41 1.38 0.0000 4.41 1.45 0.0000 

4.39 1.38 0.0000 4.39 1.38 0.0000 4.39 1.45 0.0010 

4.37 1.38 0.0000 4.37 1.38 0.0000 4.37 1.45 0.0010 

4.35 1.38 0.0010 4.35 1.38 0.0000 4.35 1.45 0.0000 

4.33 1.38 0.0010 4.33 1.38 0.0000 4.33 1.45 0.0000 

4.31 1.38 0.0000 4.31 1.38 0.0000 4.31 1.45 0.0010 

4.29 1.38 0.0000 4.29 1.38 0.0000 4.29 1.45 0.0010 

4.27 1.38 0.0000 4.27 1.38 0.0000 4.27 1.45 0.0020 

4.26 1.38 0.0000 4.26 1.38 0.0000 4.26 1.45 0.0010 

4.24 1.38 0.0000 4.24 1.38 0.0000 4.24 1.45 0.0020 

4.22 1.38 0.0000 4.22 1.38 0.0000 4.22 1.45 0.0000 

4.20 1.38 0.0000 4.20 1.38 0.0000 4.20 1.45 0.0000 

4.18 1.38 0.0000 4.18 1.38 0.0000 4.18 1.45 0.0000 

4.17 1.38 0.0010 4.17 1.38 0.0000 4.17 1.46 0.0000 

4.15 1.38 0.0000 4.15 1.38 0.0000 4.15 1.46 0.0000 

4.13 1.38 0.0000 4.13 1.38 0.0010 4.13 1.46 0.0000 

4.12 1.38 0.0000 4.12 1.38 0.0010 4.12 1.45 0.0000 

4.10 1.38 0.0000 4.10 1.38 0.0000 4.10 1.46 0.0000 

4.08 1.38 0.0000 4.08 1.38 0.0000 4.08 1.46 0.0000 

4.07 1.38 0.0000 4.07 1.38 0.0000 4.07 1.46 0.0000 

4.05 1.38 0.0000 4.05 1.38 0.0000 4.05 1.46 0.0000 

4.03 1.38 0.0000 4.03 1.38 0.0000 4.03 1.46 0.0000 

4.02 1.38 0.0000 4.02 1.38 0.0000 4.02 1.46 0.0000 

4.00 1.38 0.0000 4.00 1.38 0.0000 4.00 1.46 0.0000 

3.98 1.38 0.0000 3.98 1.38 0.0000 3.98 1.46 0.0000 

3.97 1.38 0.0000 3.97 1.38 0.0000 3.97 1.46 0.0000 

3.95 1.38 0.0000 3.95 1.38 0.0000 3.95 1.46 0.0000 

3.94 1.38 0.0000 3.94 1.38 0.0000 3.94 1.46 0.0000 

3.92 1.38 0.0000 3.92 1.38 0.0000 3.92 1.46 0.0000 

3.91 1.38 0.0000 3.91 1.39 0.0000 3.91 1.47 0.0030 

3.89 1.38 0.0000 3.89 1.39 0.0000 3.89 1.46 0.0000 

3.88 1.38 0.0010 3.88 1.38 0.0000 3.88 1.46 0.0000 

3.86 1.38 0.0000 3.86 1.39 0.0000 3.86 1.46 0.0000 

3.85 1.38 0.0000 3.85 1.39 0.0010 3.85 1.46 0.0000 

3.83 1.38 0.0010 3.83 1.38 0.0030 3.83 1.46 0.0000 

3.82 1.38 0.0030 3.82 1.38 0.0010 3.82 1.46 0.0000 

3.80 1.38 0.0010 3.80 1.38 0.0000 3.80 1.46 0.0010 

3.79 1.39 0.0000 3.79 1.39 0.0000 3.79 1.46 0.0010 

3.77 1.39 0.0000 3.77 1.39 0.0000 3.77 1.46 0.0000 

3.76 1.39 0.0000 3.76 1.39 0.0010 3.76 1.46 0.0000 

3.75 1.39 0.0010 3.75 1.39 0.0010 3.75 1.46 0.0000 

3.73 1.39 0.0010 3.73 1.38 0.0010 3.73 1.46 0.0000 

3.72 1.39 0.0000 3.72 1.38 0.0000 3.72 1.46 0.0000 

3.70 1.39 0.0010 3.70 1.39 0.0000 3.70 1.46 0.0000 

3.69 1.39 0.0010 3.69 1.39 0.0000 3.69 1.46 0.0000 

3.68 1.39 0.0010 3.68 1.39 0.0000 3.68 1.46 0.0000 

3.66 1.39 0.0000 3.66 1.39 0.0000 3.66 1.47 0.0000 

3.65 1.39 0.0000 3.65 1.39 0.0020 3.65 1.46 0.0000 
22

3.64 1.39 0.0000 3.64 1.39 0.0030 3.64 1.46 0.0000 

3.62 1.39 0.0000 3.62 1.39 0.0040 3.62 1.46 0.0000 

3.61 1.39 0.0010 3.61 1.39 0.0020 3.61 1.46 0.0010 

3.60 1.39 0.0020 3.60 1.39 0.0000 3.60 1.46 0.0010 

3.58 1.39 0.0030 3.58 1.39 0.0000 3.58 1.46 0.0000 

3.57 1.39 0.0010 3.57 1.39 0.0020 3.57 1.46 0.0000 

3.56 1.39 0.0000 3.56 1.39 0.0020 3.56 1.47 0.0000 

3.55 1.39 0.0010 3.55 1.39 0.0010 3.55 1.47 0.0000 

3.53 1.39 0.0020 3.53 1.40 0.0030 3.53 1.47 0.0010 

3.52 1.39 0.0030 3.52 1.40 0.0110 3.52 1.47 0.0000 

3.51 1.39 0.0030 3.51 1.39 0.0160 3.51 1.47 0.0000 

3.50 1.40 0.0050 3.50 1.39 0.0140 3.50 1.47 0.0030 

3.48 1.40 0.0060 3.48 1.38 0.0080 3.48 1.47 0.0050 

3.47 1.39 0.0140 3.47 1.39 0.0050 3.47 1.47 0.0030 

3.46 1.39 0.0060 3.46 1.39 0.0060 3.46 1.47 0.0050 

3.45 1.40 0.0050 3.45 1.39 0.0080 3.45 1.48 0.0100 

3.44 1.40 0.0110 3.44 1.39 0.0120 3.44 1.46 0.0030 

3.42 1.40 0.0170 3.42 1.39 0.0130 3.42 1.47 0.0070 

3.41 1.40 0.0270 3.41 1.40 0.0150 3.41 1.47 0.0120 

3.40 1.38 0.0240 3.40 1.39 0.0230 3.40 1.47 0.0090 

3.39 1.39 0.0170 3.39 1.39 0.0290 3.39 1.47 0.0100 

3.38 1.40 0.0190 3.38 1.38 0.0260 3.38 1.47 0.0130 

3.37 1.41 0.0430 3.37 1.37 0.0180 3.37 1.47 0.0180 

3.36 1.36 0.0670 3.36 1.38 0.0150 3.36 1.46 0.0300 

3.34 1.34 0.0310 3.34 1.38 0.0180 3.34 1.45 0.0240 

3.33 1.35 0.0070 3.33 1.37 0.0180 3.33 1.45 0.0150 

3.32 1.35 0.0010 3.32 1.37 0.0130 3.32 1.45 0.0060 

3.31 1.36 0.0000 3.31 1.37 0.0070 3.31 1.45 0.0020 

3.30 1.37 0.0000 3.30 1.37 0.0040 3.30 1.45 0.0010 

3.29 1.37 0.0000 3.29 1.37 0.0020 3.29 1.45 0.0000 

3.28 1.37 0.0000 3.28 1.37 0.0010 3.28 1.46 0.0010 

3.27 1.37 0.0000 3.27 1.38 0.0000 3.27 1.46 0.0020 

3.26 1.37 0.0000 3.26 1.38 0.0000 3.26 1.46 0.0020 

3.25 1.37 0.0000 3.25 1.38 0.0000 3.25 1.46 0.0030 

3.24 1.37 0.0000 3.24 1.38 0.0000 3.24 1.46 0.0010 

3.23 1.37 0.0000 3.23 1.38 0.0010 3.23 1.46 0.0000 

3.22 1.38 0.0000 3.22 1.38 0.0010 3.22 1.46 0.0000 

3.21 1.38 0.0000 3.21 1.38 0.0010 3.21 1.46 0.0000 

3.19 1.38 0.0000 3.19 1.38 0.0000 3.19 1.46 0.0000 

3.18 1.38 0.0000 3.18 1.38 0.0000 3.18 1.46 0.0000 

3.17 1.38 0.0000 3.17 1.38 0.0000 3.17 1.46 0.0000 

3.16 1.38 0.0000 3.16 1.38 0.0000 3.16 1.46 0.0000 

3.15 1.38 0.0000 3.15 1.38 0.0010 3.15 1.46 0.0000 

3.14 1.38 0.0000 3.14 1.38 0.0000 3.14 1.46 0.0000 

3.13 1.38 0.0000 3.13 1.38 0.0000 3.13 1.46 0.0000 

3.13 1.38 0.0010 3.13 1.38 0.0000 3.13 1.46 0.0000 

3.12 1.38 0.0000 3.12 1.38 0.0000 3.12 1.46 0.0010 

3.11 1.38 0.0000 3.11 1.38 0.0000 3.11 1.46 0.0000 

3.10 1.38 0.0000 3.10 1.36 0.0000 3.10 1.46 0.0000 

3.09 1.38 0.0000 3.09 1.38 0.0000 3.09 1.46 0.0000 

3.08 1.38 0.0000 3.08 1.38 0.0000 3.08 1.46 0.0000 

3.07 1.38 0.0000 3.07 1.38 0.0000 3.07 1.45 0.0000 

3.06 1.38 0.0000 3.06 1.38 0.0000 3.06 1.48 0.0000 
23

3.05 1.38 0.0000 3.05 1.38 0.0000 3.05 1.46 0.0000 

3.04 1.38 0.0000 3.04 1.39 0.0010 3.04 1.46 0.0000 

3.03 1.38 0.0000 3.03 1.38 0.0010 3.03 1.46 0.0000 

3.02 1.38 0.0000 3.02 1.38 0.0000 3.02 1.46 0.0000 

3.01 1.39 0.0000 3.01 1.38 0.0000 3.01 1.45 0.0000 

3.00 1.39 0.0000 3.00 1.39 0.0000 3.00 1.46 0.0000 

2.99 1.38 0.0000 2.99 1.39 0.0000 2.99 1.47 0.0000 

2.99 1.38 0.0000 2.99 1.39 0.0000 2.99 1.46 0.0000 

2.98 1.38 0.0000 2.98 1.38 0.0000 2.98 1.47 0.0000 

2.97 1.38 0.0000 2.97 1.38 0.0000 2.97 1.46 0.0000 

2.96 1.38 0.0000 2.96 1.38 0.0000 2.96 1.47 0.0000 

2.95 1.38 0.0000 2.95 1.39 0.0000 2.95 1.49 0.0000 

2.94 1.39 0.0000 2.94 1.39 0.0000 2.94 1.47 0.0000 

2.93 1.39 0.0000 2.93 1.39 0.0000 2.93 1.47 0.0000 

2.92 1.39 0.0000 2.92 1.39 0.0010 2.92 1.47 0.0000 

2.92 1.38 0.0010 2.92 1.38 0.0000 2.92 1.46 0.0000 

2.91 1.38 0.0000 2.91 1.38 0.0000 2.91 1.47 0.0000 

2.90 1.38 0.0000 2.90 1.39 0.0000 2.90 1.47 0.0000 

2.89 1.38 0.0000 2.89 1.39 0.0000 2.89 1.47 0.0000 

2.88 1.38 0.0000 2.88 1.39 0.0000 2.88 1.47 0.0000 

2.87 1.38 0.0000 2.87 1.39 0.0000 2.87 1.47 0.0000 

2.87 1.39 0.0000 2.87 1.39 0.0000 2.87 1.47 0.0000 

2.86 1.39 0.0000 2.86 1.39 0.0000 2.86 1.47 0.0000 

2.85 1.39 0.0000 2.85 1.39 0.0000 2.85 1.47 0.0000 

2.84 1.39 0.0000 2.84 1.39 0.0000 2.84 1.47 0.0000 

2.83 1.39 0.0000 2.83 1.39 0.0000 2.83 1.46 0.0000 

2.82 1.38 0.0000 2.82 1.39 0.0000 2.82 1.47 0.0000 

2.82 1.38 0.0000 2.82 1.39 0.0000 2.82 1.47 0.0000 

2.81 1.39 0.0000 2.81 1.39 0.0000 2.81 1.47 0.0000 

2.80 1.39 0.0000 2.80 1.39 0.0000 2.80 1.47 0.0000 

2.79 1.39 0.0000 2.79 1.39 0.0000 2.79 1.47 0.0000 

2.79 1.38 0.0000 2.79 1.39 0.0000 2.79 1.47 0.0000 

2.78 1.39 0.0000 2.78 1.39 0.0000 2.78 1.47 0.0000 

2.77 1.38 0.0000 2.77 1.39 0.0000 2.77 1.47 0.0000 

2.76 1.39 0.0000 2.76 1.39 0.0000 2.76 1.47 0.0000 

2.75 1.39 0.0000 2.75 1.39 0.0000 2.75 1.46 0.0010 

2.75 1.39 0.0000 2.75 1.39 0.0000 2.75 1.47 0.0000 

2.74 1.38 0.0000 2.74 1.39 0.0010 2.74 1.47 0.0000 

2.73 1.39 0.0000 2.73 1.39 0.0000 2.73 1.47 0.0000 

2.72 1.39 0.0000 2.72 1.39 0.0000 2.72 1.47 0.0000 

2.72 1.39 0.0000 2.72 1.39 0.0000 2.72 1.47 0.0000 

2.71 1.39 0.0000 2.71 1.39 0.0000 2.71 1.47 0.0000 

2.70 1.39 0.0000 2.70 1.39 0.0000 2.70 1.47 0.0000 

2.70 1.39 0.0000 2.70 1.39 0.0000 2.70 1.47 0.0000 

2.69 1.39 0.0000 2.69 1.39 0.0000 2.69 1.47 0.0000 

2.68 1.39 0.0000 2.68 1.39 0.0000 2.68 1.47 0.0000 

2.67 1.39 0.0000 2.67 1.39 0.0000 2.67 1.47 0.0000 

2.67 1.39 0.0000 2.67 1.39 0.0000 2.67 1.47 0.0000 

2.66 1.39 0.0000 2.66 1.39 0.0000 2.66 1.47 0.0000 

2.65 1.39 0.0000 2.65 1.39 0.0000 2.65 1.47 0.0000 

2.65 1.39 0.0000 2.65 1.39 0.0000 2.65 1.47 0.0000 

2.64 1.39 0.0000 2.64 1.39 0.0010 2.64 1.47 0.0000 

2.63 1.39 0.0000 2.63 1.39 0.0010 2.63 1.47 0.0000 
24

2.62 1.39 0.0000 2.62 1.39 0.0020 2.62 1.47 0.0000 

2.62 1.39 0.0000 2.62 1.39 0.0020 2.62 1.46 0.0000 

2.61 1.39 0.0000 2.61 1.39 0.0010 2.61 1.47 0.0000 

2.60 1.39 0.0000 2.60 1.39 0.0000 2.60 1.47 0.0000 

2.60 1.39 0.0000 2.60 1.39 0.0000 2.60 1.47 0.0000 

2.59 1.39 0.0000 2.59 1.39 0.0010 2.59 1.47 0.0000 

2.58 1.39 0.0000 2.58 1.39 0.0010 2.58 1.47 0.0000 

2.58 1.39 0.0000 2.58 1.39 0.0000 2.58 1.47 0.0000 

2.57 1.39 0.0000 2.57 1.39 0.0000 2.57 1.47 0.0000 

2.56 1.39 0.0000 2.56 1.39 0.0000 2.56 1.47 0.0000 

2.56 1.39 0.0000 2.56 1.39 0.0000 2.56 1.47 0.0000 

2.55 1.39 0.0000 2.55 1.39 0.0000 2.55 1.47 0.0000 

2.54 1.39 0.0000 2.54 1.39 0.0000 2.54 1.47 0.0000 

2.54 1.39 0.0000 2.54 1.39 0.0000 2.54 1.47 0.0000 

2.53 1.39 0.0000 2.53 1.39 0.0000 2.53 1.47 0.0000 

2.53 1.39 0.0000 2.53 1.39 0.0000 2.53 1.47 0.0000 

2.52 1.39 0.0000 2.52 1.39 0.0000 2.52 1.47 0.0000 

2.51 1.39 0.0000 2.51 1.39 0.0010 2.51 1.47 0.0000 

2.51 1.39 0.0000 2.51 1.39 0.0000 2.51 1.47 0.0000 

2.50 1.39 0.0000 2.50 1.39 0.0000 2.50 1.47 0.0000 

2.50 1.41 0.0003 2.50 1.40 0.0005 2.50 1.49 0.0003 

2.48 1.41 0.0004 2.49 1.40 0.0006 2.49 1.49 0.0003 

2.46 1.41 0.0005 2.48 1.40 0.0006 2.48 1.49 0.0004 

2.44 1.41 0.0006 2.47 1.40 0.0007 2.47 1.49 0.0004 

2.42 1.41 0.0005 2.46 1.40 0.0007 2.46 1.49 0.0003 

2.40 1.41 0.0004 2.45 1.40 0.0005 2.45 1.49 0.0006 

2.38 1.41 0.0003 2.44 1.40 0.0004 2.44 1.49 0.0006 

2.36 1.41 0.0003 2.43 1.40 0.0004 2.43 1.49 0.0006 

2.34 1.41 0.0005 2.42 1.40 0.0004 2.42 1.49 0.0006 

2.32 1.41 0.0009 2.41 1.40 0.0004 2.41 1.49 0.0006 

2.30 1.41 0.0008 2.40 1.40 0.0005 2.40 1.49 0.0005 

2.28 1.41 0.0006 2.39 1.40 0.0006 2.39 1.49 0.0004 

2.26 1.41 0.0006 2.38 1.40 0.0006 2.38 1.49 0.0004 

2.24 1.41 0.0002 2.37 1.40 0.0004 2.37 1.49 0.0003 

2.22 1.41 0.0001 2.36 1.40 0.0003 2.36 1.49 0.0004 

2.20 1.41 0.0001 2.35 1.40 0.0004 2.35 1.49 0.0005 

2.18 1.41 0.0001 2.34 1.40 0.0003 2.34 1.49 0.0005 

2.16 1.41 0.0001 2.33 1.41 0.0004 2.33 1.49 0.0004 

2.14 1.41 0.0001 2.32 1.41 0.0005 2.32 1.49 0.0004 

2.12 1.41 0.0001 2.31 1.41 0.0003 2.31 1.49 0.0006 

2.10 1.41 0.0001 2.30 1.41 0.0003 2.30 1.49 0.0007 

2.08 1.41 0.0000 2.29 1.41 0.0004 2.29 1.49 0.0005 

2.06 1.41 0.0000 2.28 1.41 0.0006 2.28 1.49 0.0004 

2.04 1.41 0.0000 2.27 1.41 0.0013 2.27 1.49 0.0005 

2.02 1.41 0.0000 2.26 1.41 0.0012 2.26 1.49 0.0008 

2.00 1.41 0.0000 2.25 1.41 0.0012 2.25 1.49 0.0005 

1.98 1.41 0.0000 2.24 1.40 0.0009 2.24 1.49 0.0003 

1.96 1.41 0.0000 2.23 1.40 0.0006 2.23 1.49 0.0002 

1.94 1.41 0.0000 2.22 1.40 0.0004 2.22 1.49 0.0001 

1.92 1.41 0.0000 2.21 1.41 0.0002 2.21 1.49 0.0001 

1.90 1.41 0.0000 2.20 1.41 0.0002 2.20 1.49 0.0001 

1.88 1.41 0.0000 2.19 1.41 0.0001 2.19 1.49 0.0001 

1.86 1.41 0.0000 2.18 1.41 0.0001 2.18 1.49 0.0001 
25

1.84 1.41 0.0000 2.17 1.41 0.0001 2.17 1.49 0.0001 

1.82 1.41 0.0000 2.16 1.41 0.0001 2.16 1.49 0.0002 

1.80 1.41 0.0000 2.15 1.41 0.0001 2.15 1.49 0.0001 

1.78 1.41 0.0000 2.14 1.41 0.0000 2.14 1.49 0.0002 

1.76 1.41 0.0001 2.13 1.41 0.0000 2.13 1.49 0.0001 

1.74 1.41 0.0001 2.12 1.41 0.0000 2.12 1.49 0.0001 

1.72 1.41 0.0001 2.11 1.41 0.0000 2.11 1.49 0.0001 

1.70 1.41 0.0001 2.10 1.41 0.0000 2.10 1.49 0.0000 

1.68 1.41 0.0001 2.09 1.41 0.0000 2.09 1.49 0.0000 

1.66 1.41 0.0000 2.08 1.41 0.0000 2.08 1.49 0.0000 

1.64 1.41 0.0000 2.07 1.41 0.0000 2.07 1.49 0.0000 

1.62 1.41 0.0000 2.06 1.41 0.0000 2.06 1.49 0.0000 

1.59 1.41 0.0000 2.05 1.41 0.0000 2.05 1.49 0.0000 

1.57 1.41 0.0000 2.04 1.41 0.0000 2.04 1.49 0.0000 

1.55 1.41 0.0000 2.03 1.41 0.0000 2.03 1.49 0.0000 

1.53 1.41 0.0000 2.02 1.41 0.0000 2.02 1.49 0.0000 

1.51 1.41 0.0000 2.01 1.41 0.0000 2.01 1.49 0.0000 

1.49 1.41 0.0000 2.00 1.41 0.0000 2.00 1.49 0.0000 

1.47 1.41 0.0000 1.99 1.41 0.0000 1.99 1.49 0.0000 

1.45 1.41 0.0000 1.98 1.41 0.0000 1.98 1.49 0.0000 

1.43 1.41 0.0000 1.97 1.41 0.0000 1.97 1.49 0.0000 

1.41 1.41 0.0000 1.96 1.41 0.0000 1.96 1.49 0.0000 

1.39 1.41 0.0000 1.95 1.41 0.0000 1.95 1.49 0.0000 

1.37 1.41 0.0000 1.94 1.41 0.0000 1.94 1.49 0.0000 

1.35 1.41 0.0000 1.93 1.41 0.0000 1.93 1.50 0.0000 

1.33 1.41 0.0000 1.92 1.41 0.0000 1.92 1.50 0.0000 

1.31 1.41 0.0000 1.91 1.41 0.0000 1.91 1.50 0.0000 

1.29 1.41 0.0000 1.90 1.41 0.0000 1.90 1.50 0.0000 

1.27 1.41 0.0000 1.89 1.41 0.0000 1.89 1.50 0.0000 

1.25 1.41 0.0000 1.88 1.41 0.0000 1.88 1.50 0.0000 

1.23 1.41 0.0000 1.87 1.41 0.0000 1.87 1.50 0.0000 

1.21 1.41 0.0000 1.86 1.41 0.0000 1.86 1.50 0.0000 

1.19 1.41 0.0000 1.85 1.41 0.0000 1.85 1.50 0.0000 

1.17 1.41 0.0000 1.84 1.41 0.0000 1.84 1.50 0.0000 

1.15 1.41 0.0000 1.83 1.41 0.0000 1.83 1.50 0.0000 

1.13 1.41 0.0000 1.82 1.41 0.0000 1.82 1.50 0.0000 

1.11 1.41 0.0000 1.81 1.41 0.0000 1.81 1.50 0.0000 

1.09 1.41 0.0000 1.80 1.41 0.0000 1.80 1.50 0.0000 

1.07 1.41 0.0000 1.79 1.41 0.0000 1.79 1.50 0.0000 

1.05 1.41 0.0000 1.78 1.41 0.0000 1.78 1.50 0.0000 

1.03 1.41 0.0000 1.77 1.41 0.0000 1.77 1.50 0.0000 

1.01 1.41 0.0000 1.76 1.41 0.0000 1.76 1.50 0.0000 

0.99 1.41 0.0000 1.75 1.41 0.0000 1.75 1.50 0.0000 

0.97 1.41 0.0000 1.74 1.41 0.0000 1.74 1.50 0.0000 

0.95 1.41 0.0000 1.73 1.41 0.0001 1.73 1.50 0.0001 

0.93 1.42 0.0000 1.72 1.41 0.0001 1.72 1.50 0.0001 

0.91 1.42 0.0000 1.71 1.41 0.0001 1.71 1.50 0.0001 

0.89 1.42 0.0000 1.70 1.41 0.0001 1.70 1.50 0.0001 

0.87 1.42 0.0000 1.69 1.41 0.0001 1.69 1.50 0.0001 

0.85 1.42 0.0000 1.68 1.41 0.0001 1.68 1.50 0.0001 

0.83 1.42 0.0000 1.67 1.41 0.0001 1.67 1.50 0.0001 

0.81 1.42 0.0000 1.66 1.41 0.0001 1.66 1.50 0.0001 
26

1. Querry, Marvin R. Optical constants of minerals and other materials from the millimeter to 

the ultraviolet; Chemical Research, Development and Engineering Center technical report, 

CRDEC-CR88009; November 1987. 

2. Wieliczka, D. M.; Querry, M. R. Four Techniques to Measure Complex Refractive Indices 

of Liquids and Solids at Carbon Dioxide Laser Wavelengths in the Infrared Spectral Region; 

U.S. Army Chemical Research, Development & Engineering Center Technical Report, 

Report # CRDEC-CR-062, January 1990. 
27

Appendix B. IR Absorptance Spectra for DMMP, DIMP, and DEMP 

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

2 3 4 5 6 7 8 9 10 11 12 13 14

Wavelength (μm)

Absorptance

DMMP

Figure B-1. Measured absorptance spectra for 1 cm path of liquid phase dimethyl-methylphosphonate 

(DMMP). 
28

-0.001

0.019

0.039

0.059

0.079

0.099

0.119

0.139

2 3 4 5 6 7 8 9 10 11 12 13 14

Wavelength (μm)

Absorptance

DIMP

Figure B-2. Measured absorptance spectra for 1 cm path of liquid phase diisopropyl-methylphosphonate 

(DIMP).
29

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

2 3 4 5 6 7 8 9 10 11 12 13 14

Wavelength (μm)

Absorptance

DEMP

Figure B-3. Measured absorptance spectra for 1 cm path of liquid diethyl methylphosphonate (DEMP).
30

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