JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 107, NO. D20, 4440, doi:10.1029/2001JD002048, 2002

Quantum yields of O(1D) formation in the photolysisof ozone between 230 and 308 nm
Kenshi Takahashi, Shinsuke Hayashi, and Yutaka Matsumi
Solar-Terrestrial Environment Laboratory and Graduate School of Science, Nagoya University, Aichi, Japan

Nori Taniguchi
Department of Molecular Engineering, Kyoto University, Kyoto, Japan

Sachiko Hayashida
Faculty of Science, Nara Women’s University, Nara, Japan
Received 31 December 2001; revised 3 May 2002; accepted 3 May 2002; published 25 October 2002.

[1] Ozone molecules are photolyzed in the strong photoabsorption band of the Hartleyband at 230–308 nm, and the O(3Pj) photofragments produced by the photolysis aredetected directly by a technique of laser-induced fluorescence around 130 nm. The
quantum yield values for O(1D) formation in the photolysis of ozone at 297 ± 2 K are
determined as a function of the photolysis wavelength, using the O(1D) quantum yieldvalue of 0.79 at 308 nm as a reference. The O(1D) quantum yield values obtained arefound to be almost independent of the photolysis wavelength over the Hartley band(0.91). The results are compared with the values measured previously using various
experimental techniques and also with the recommendation values for use in atmosphericmodeling. The effects of the present yield data on the O(1D) production rates from ozone
photolysis in the stratosphere are evaluated. Impact of our new O(1D) quantum yieldvalues on the stratospheric chemistry has also been explored using a one-dimensional
photochemical model. The smaller O(1D) production rates as compared to the latest
NASA/JPL recommendation values are followed by changes in the efficiency of thechemical chain reactions involving HOx, NOx, and ClOx and result in the higher O3
concentrations throughout the stratosphere.
INDEX TERMS: 0317 Atmospheric Composition and
Structure: Chemical kinetic and photochemical properties; 0340 Atmospheric Composition and Structure:
Middle atmosphere—composition and chemistry; 0365 Atmospheric Composition and Structure:
Troposphere—composition and chemistry; KEYWORDS: Ozone, oxygen atom, photolysis, quantum yield,
ultraviolet, stratosphere
Citation: Takahashi, K., S. Hayashi, Y. Matsumi, N. Taniguchi, and S. Hayashida, Quantum yields of O(1D) formation in thephotolysis of ozone between 230 and 308 nm, J. Geophys. Res., 107(D20), 4440, doi:10.1029/2001JD002048, 2002.

1. Introduction[2] O3 plays several extremely important roles in the
Earth’s atmosphere [Wayne, 2000]. Production of atomic
oxygen from the photodissociation of O3 has been a subjectof interest to atmospheric scientists [Ravishanakara et al.,
1998; Brasseur et al., 1999; Finlayson-Pitts and Pitts,
1999]. Many experimental and theoretical studies haveshown that there are two primary pathways in the Hartleyband photolysis of O3 at 220– 308 nm; O3 þ hn ! O 1 D þ O2 a1 g

ð1Þ



 
! O 3 P þ O2 X3 
g :

ð2Þ

Copyright 2002 by the American Geophysical Union.
0148-0227/02/2001JD002048$09.00

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Both processes are spin-allowed from the singlet state ofozone. Table 1 lists the results from previous measurementsof the channel branching ratios between channels (1) and (2)in the Hartley band.
[3] A pioneering study by Fairchild et al. [1978] indicatedthat the formation of O(1D), channel (1), is dominant over the
Hartley band. They photolyzed O3 molecules at 274 nm andmeasured the time-of-flight (TOF) spectrum of the fragments. The analysis of the spectrum indicated that thebranchings between channels (1) and (2) are 0.9 and0.1, respectively. Sparks et al. [1980] also performedexperiments at 266 nm using a mass spectrometric detection
technique with a molecular beam and reported the channel
branching ratio of 0.1 for the O(3P) formation.
[4] The time-resolved resonance fluorescence detection
techniques for O(3P) fragments following O3 photolysis
were also applied to determine the absolute branching ratio
between channels (1) and (2) [Amimoto et al., 1980; Brock
and Watson, 1980; Wine and Ravishankara, 1982; Green-

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TAKAHASHI ET AL.: YIELD OF O(1D) IN OZONE PHOTOLYSIS

Table 1. Summary of O(1D) Quantum Yield Measurements in the Photolysis of O3 Between 220 and 300 nm at Room Temperaturela1D(l)b222
221 – 243.5d
228.5, 231
248
248
248
248
253.6
266
266
274
266 – 300d
274 – 300d
297 – 300d
270 – 300d
290 – 295d
295 – 300d
297 – 300d0.87 ± 0.04
0.87 – 0.88e
0.83 ± 0.04
0.85 ± 0.02
0.91 ± 0.03
0.94 ± 0.01
0.91 ± 0.06
0.92 ± 0.04
0.88 ± 0.02
0.9
0.9
0.85 – 0.92e
0.86 – 1.10e
0.95 – 1.00e–f0.90 – 0.92e
0.86 – 0.91e
0.88 – 0.89e

Technique

Notec

ReferenceO( P) resonance fluorescence
O(1D) fluorescence
O(1D) fluorescence
O(3P) resonance fluorescence
O(3P) resonance fluorescence
O(3P) resonance fluorescence
O(3P) resonance fluorescencedecrease in O3 pressure
O(3P) resonance fluorescencetime-of-flight mass
time-of-flight mass
O2(1) CARS
CO2 infrared fluorescenceNO2 chemiluminescenceO2(1) multiphoton ionization
OH laser induced fluorescenceNO2 chem-ionization mass.
O(3P) laser induced fluorescence

Absolute
1D(248) = 0.91
1D(266) = 0.88
Absolute
Absolute
Absolute
Absolute
Absolute
Absolute
Absolute
Absolute
Absolute
1D(308) = 0.79
1D(300) = 1.00
1D(290 – 300) = 0.95
1D(308) = 0.79
1D(308) = 0.79
1D(308) = 0.79

Turnipseed et al. [1991]
Cooper et al [1993]
Cooper et al [1993]
Amimoto et al. [1980]
Wine and Ravishankara [1982]
Greenblatt and Weisenfeld [1983]
Talukdar et al. [1997]
Cobos et al. [1983]
Brock and Watson [1980]
Sparks et al. [1980]
Fairchild et al. [1978]
Valentini et al. [1987]
Trolier and Wiesenfeld [1988]
Brock and Watson [1980]
Ball et al. [1993]
Talukdar et al. [1998]
Smith et al. [2000]
Taniguchi et al. [2000]

3a

Photolysis wavelength in nm.
O(1D) quantum yield at the photolysis wavelength l.
Reference value of 1D(l) at the photolysis wavelength l is indicated, when a relative method was used in the measurement.
dValues of 1D(l) were measured at a number of points in the wavelength range indicated.
eReported values lie in the range indicated.
fValues of 1D(l) were not presented numerically in the original paper.
bcblatt and Wiesenfeld, 1983; Turnipseed et al., 1991; Talukdar et al., 1997] at various wavelengths between 222 and308 nm. Microwave powered oxygen lamps were used todetect the O(3Pj) fragments by either atomic absorption oremission spectroscopy at the resonance line for the 33S1 –23Pj transition around 130 nm. In those experiments, time
evolutions of the O(3Pj) signal after the laser flash photolysis of O3 were measured. The time profiles showed aprompt rise due to the direct formation of O(3P) from thephotolysis of O3 in the primary step and a subsequent slow
increase as a consequence of the secondary reactions forming O(3P) from O(1D). The secondary reactions of theO(1D) atoms with O3 molecules are
 
 
 
O 1 D þ O3 ! O 3 P þ O 3 P þ O2
 
O 1 D þ O3 ! 2 O2

k3b :

k3a

ð3aÞ
ð3bÞ

The rate constants of k3a and k3b have been measured to beequal, and the reaction of one O(1D) with O3 leads to one
O(3P) on the average [DeMore et al., 1997; Talukdar et al.,1997]. Thus the absolute branching ratios were determinedby analyzing the time profiles of O(3P) signal intensity,
based on the result of k3a/k3b = 1.0 in the kinetic studies.
Valentini et al. [1987] used coherent anti-Stokes Raman(CARS) spectroscopy to probe the O2(1g) fragments fromO3 photolysis around 280 nm. They determined absolute
quantum yields for O2(1g) formation under some assumptions. The O2(1g) quantum yields should reflect the O(1D)
quantum yields, since the dissociation channel (1) is thought
to be predominant for O(1D) formation in the Hartley band
photolysis.
[5] Cooper et al. [1993] detected the O(1D) atoms fromthe photodissociation of O3 between 221 and 243.5 nm byobserving the weak fluorescence at 630 nm from the spinforbidden 1D2 ! 3P transition and measured the relative
O(1D) quantum yields. Ball et al. [1993] used a technique ofresonance enhanced multiphoton ionization (REMPI) to
detect the O2(1g) fragments and reported the relative

quantum yield for O2(1g) formation between 287 and329 nm. The detection of O(1D) using secondary reactions
after the photolysis of O3 at 248 nm was carried out by
Talukdar et al. [1998]. They observed the laser-induced
fluorescence of OH radicals which were produced by thereaction of the O(1D) atoms with H2O or CH4. They foundthat the O(1D) quantum yield is independent of temperature
between 200 and 320 K in the photolysis of O3 at 248 nm.
[6] The NASA/JPL panel has recommended the quantum
yield value of 0.95 over the Hartley band between 240 and
300 nm for use in the stratospheric modeling [Sander et al.,2000]. The IUPAC subcommittee [Atkinson et al., 1997]
have recommended the formula of (1.98 – 301/l) for thephotolysis wavelength l between 271 and 300 nm and aconstant value of 0.87 for 222 < l < 271 nm.
[7] In the present study the O(3Pj) atoms produced in the
Hartley band photolysis of O3 between 230 and 308 nm are
directly detected by laser-induced fluorescence in the vacuum UV region (VUV-LIF). Using the VUV-LIF technique,the absolute quantum yields of O(1D) and O(3P) formationfrom O3 photolysis between 297 and 329 nm have beenmeasured previously by our group [Takahashi et al., 1996a;
1996b; 1997; 1998; Taniguchi et al., 2000]. This is the firstreport on the systematic measurements of the O(1D) quantum yields from ozone photolysis in the wide range of
wavelength in the UV region. As a photolysis light source inthis study, an optical parametric oscillator (OPO) with asecond harmonic generator, which allowed us to generate
tunable UV light in the wide wavelength range, was used.
The results obtained in this work were compared with bothpreviously reported values and the recent recommendations
for atmospheric modeling by NASA/JPL panel [Sander etal., 2000] and IUPAC subcommittee [Atkinson et al., 1997].

2. Experimental[8] The experimental arrangement and procedures are
essentially the same as in our previous studies on O3
photolysis [Takahashi et al., 1996a; Taniguchi et al,

TAKAHASHI ET AL.: YIELD OF O(1D) IN OZONE PHOTOLYSIS

Figure 1. Schematic diagram of experimental setup usedin this study. PM: power meter, ND: neutral density opticalfilter, and PC: personal computer.
2000], except for the photolysis light source. The schematic
diagram for the experimental setup is depicted in Figure 1.
The O(3P2) photoproducts were directly detected by the
VUV-LIF method using the 3s 3 S o -2p 3 P 2 transition at
130.22 nm. The VUV probe laser was obtained by four-wave
mixing in Krypton gas. The output of a XeCl excimer laser(Lambda Physik, LEXtra 50) was split by a dichroic beam
splitter (50%/50%) and used to pump simultaneously two
tunable dye lasers (Lambda Physik, Scanmate 2 andFL3002). One dye laser operating at 425.12 nm was frequency doubled in b-BaB2O4 (BBO) crystal. The UV output
was tuned to the wavelength resonant with the two-photon
1
S0 – 5p[1/2]0 transition of Kr at 212.55 nm. The second dyelaser was operated at 578.1, 572.8, and 570.6 nm, fordetection of three spin-orbit states of j = 2, 1, and 0 ofO(3Pj), respectively. The two laser beams were mixed using adichroic beam splitter and focused with a fused silica lens ( f =200 mm) into a cell containing 15 Torr of Kr. The resultant
VUV light was passed through the MgF2 window andintroduced into the photolysis chamber. A fraction of the
VUV light passed through the photolysis chamber wasreflected by an MgF2 beam splitter held in the end of thephotolysis chamber and led into a cell containing 3 Torr ofnitric oxide (NO). Since the ionization potential of NO is 9.24
eV, the VUV photons at 130 nm ionize NO molecules. The
photoionization current from the NO cell was monitored tomeasure the relative intensity variation of the VUV light. Theline width of the VUV laser was about 0.8 cm1, which wasestimated from the line shape of the resonance line ofthermalized O(3Pj) atoms.
[9] The photolysis laser light, which was tunable over therange 230– 308 nm, was generated using a Nd: YAG laser
pumped OPO laser operating at 10 Hz repetition rate
(Continuum, Panther OPO and Powerlite 8010), and subsequent frequency doubling using a BBO crystal with anauto-tracking system. The wavelength calibration of the
OPO signal light was achieved simultaneously with meas-

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11 - 3urements of the O(3P) spectra by introducing a part of the
OPO signal light into a wavemeter (Burleigh, WA-4500).
Typical output power of the UV laser light was 1 –3 mJ/
pulse and the bandwidth was about 6 cm1(FWHM). A
neutral density filter was inserted in the beam path to obtain
the appropriate photolysis laser power at various wavelengths. A linear dependence of the O(3P) LIF signal on the
UV photolysis laser power was checked at several photolysis wavelengths. The typical results at the photolysis
wavelength at 266 nm are shown in Figure 2. During theexperiments, the UV laser power was monitored on a shotby-shot basis using a pyroelectric laser power meter (Molectron, J4-09). A part of the UV photolysis laser was reflectedby a thin fused silica plate onto the power meter. We also
monitored the photolysis laser power with a calorimeter(Scientech, AC50UV) by inserting the detector head into
the photolysis laser beam path in front of the LIF cell after
every LIF measurement. The beam diameter of the photolysis laser was about 5 mm, while that of the probe laser was
about 1 mm. The path length of the photolysis laser beamfrom the inlet to the observation region was about 10 cm.
[10] The photolysis and probe laser beams were counterpropagated and the time delay between the two laser pulses
was controlled by a pulse delay controller (Stanford
Research, DG535). The delay time was 100 ns with a time
jitter less than 5 ns. The LIF of O(3P) was detected along
the vertical axis, orthogonal to the propagation direction ofboth VUV probe and photolysis laser beams, using a solarblind photomultiplier tube (PMT) (EMR, 541J-08-17). The
PMT has a LiF window and a KBr photocathode that issensitive only between 105 and 150 nm. The output fromthe PMT was preamplified and fed into a gated integrator(Stanford Research, SR-250).
[11] The reaction chamber was evacuated by a rotary
pump (330 Liter/min). The ozone gas was synthesized from

Figure 2. Photolysis laser power dependence of the laserinduced fluorescence intensity for the O(1D) atoms in theozone photolysis at 266 nm. A straight line indicates theresult of linear least squares fit analysis.

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TAKAHASHI ET AL.: YIELD OF O(1D) IN OZONE PHOTOLYSIS

ultrapure O2 (Nagoya Kosan, 99.9995%) by a silent discharge ozonizer. The O3 gas was flowed slowly into thereaction chamber through a polytetrafluoroethylene tube.
Helium gas was added as a buffer gas. The total pressure in
the reaction cell was maintained to be 1.5 Torr. The partialpressure of O3/O2 was 0.35 Torr and which of about 3% was
O3. The pressure was measured with a capacitance manometer (MKS, Baratron, 2 Torr full scale). It should be
noted that the high sensitivity of the VUV-LIF techniquemakes it possible to detect O(3Pj) atoms at such lowpressure and short pump-probe delay time, and that secondary reactions can be safely ignored. For example, the rate
constant for the reaction O(1D) + O2(X3g ) is reported to be
4  1011 cm3 molecule1 s1 and that of O(1D) + O3 toform 2O(3P) is 1.2  1010 cm3 molecule1 s1 at 298 K[Sander et al., 2000]. Helium used as the buffer gas isinefficient quencher for O(1D), that is, the rate constant is<5  1014 cm3 molecule1 s1at 298 K [Stief et al., 1975].
We estimated that the formation of O(3Pj) atoms throughthese reactions from O(1D) is less than 0.5% under our
experimental conditions. All experiments in the present
study were performed at room temperature (297 ± 2 K).

3. Results[12] Figure 3 shows a typical example of the O(3P)
quantum yield measurements, in which O3 molecules were
photolyzed by UV laser pulses at 308 and 266 nm alternatively, and the O(3P2) photofragments were probed
directly by the VUV-LIF method. The detection wavelength
for O(3P2) atoms was fixed at 130.22 nm, which was thepeak wavelength of the electronic transition of 3s3S o-2p3P2.
The absolute quantum yield of 0.79 for O(1D), that is, theyield of 0.21 for O(3P) at the photolysis wavelength of 308
nm was used as the reference value to obtain the yields at
the wavelengths between 230 and 308 nm. The yield valueof 0.79 at 308 nm is based on the recent review paper[Matsumi et al., 2001] that recommended the quantum yieldvalues for O(1D) formation in the photodissociation of O3 asa function of the wavelength and temperature for use inatmospheric modeling. In the yield measurements, thewavelength of the photolysis laser was changed alternatively between the reference (308 nm) and target wavelengths, as shown in Figure 3. From the comparison of
signal intensities at the two photolysis wavelengths, we
obtained the quantum yield values for O(3P) formation in
the photodissociation of O3, using the following expression:3P ðlÞ ¼ 3P ð308Þ SðlÞ Ið308Þ sð308Þ
;Sð308Þ IðlÞ sðlÞ

ð4Þ

where 3P(l) is the O(3P) quantum yield at a photolysis
wavelength l , S(l) is the LIF intensity which is correctedby intensity variation of the VUV probe laser, I(l) is thephoton flux of the UV photolysis laser, s(l) is the O3
absorption cross section reported by Malicet et al. [1995],
and 3P(308) is the quantum yield for O(3P) formation at
308 nm (0.21). The O(1D) quantum yield as a function of
wavelength is given by:1D ðlÞ ¼ 1  3P ðlÞ:

ð5ÞFigure 3. Typical experimental results for the O(3P)
quantum yield measurements in the photolysis of O3 at
297 ± 2 K. (a) Laser-induced fluorescence intensity ofO(3P2) atoms at 266 and 308 nm. (b) Photolysis laser power
at 266 and 308 nm. Arrows indicate the time periods inwhich the photolysis laser is introduced into the reaction
chamber and the LIF signal is detected.
At the photolysis wavelengths shorter than 237 nm, theformation of O(1S) is energetically possible [Okabe, 1978]: O3 þ hnðl < 237 nmÞ ! O 1 S þ O2 X3 
g :

ð6Þ

However, the dissociation process (6) is spin-forbidden andthe upper limit for the O(1S ) quantum yield has beenreported to be 0.1% between 170 and 240 nm [Lee et al.,1980]. It is thus reasonable to ignore the contribution of theprocess (6) between 230 and 237 nm.
[13] Figure 3 shows the signal intensities of O(3Pj, j = 2)
produced from the photolysis of ozone at 266 and 308 nm in
the VUV-LIF spectroscopy. The photodissociation process(2) produces not only the j = 2 spin-orbit state of O(3Pj) but
also j = 1 and 0 states. Under our experimental conditions thatthe total pressure is 1.5 Torr and the delay time is 100 ns, the jpopulations are partly relaxed toward the Boltzmann distribution [Abe et al., 1994]. We measured the relative j-populations among the O(3Pj) j = 2, 1, and 0 states from ozone
photolysis at several wavelengths in the range of 230– 308
nm under the same experimental conditions as the quantum
yield measurements. The relative j-populations obtained inthis study are summarized in Table 2. There is no remarkabledependence on the photolysis wavelength in the spin-orbit
populations within the experimental errors in this wavelength
range. This indicates that the relative signal intensities of thej = 2 can be used in the calculations of the total O(3Pj)
formation yield in equation (4).
[14] The signal intensities shown in Figure 3 were measured when the probe VUV laser wavelength was fixed at thepeak of the O(3s3S o – 2p3P2) transition. If the line width of the

TAKAHASHI ET AL.: YIELD OF O(1D) IN OZONE PHOTOLYSIS
Table 2. Relative Populations Among the Three Spin-Orbit Statesof O(3Pj) Produced in the Ultraviolet Photolysis of O3 Between
230 and 308 nm Under Our Experimental Conditions
O(3Pj)

Photolysis
Wavelength, nm

j=2

j=1

j=0

238
263
287

0.64 ± 0.03
0.66 ± 0.04
0.65 ± 0.03

0.28 ± 0.02
0.27 ± 0.03
0.25 ± 0.03

0.08 ± 0.01
0.07 ± 0.01
0.10 ± 0.02

spectral shape for the O(3P2) fragments due to the Doppler
broadening were strongly dependent on the photolysis wavelength, the intensities of the O(3P2) fragments at the peaks
might not be proportional to the total O(3P) yields. We
measured the line profiles of nascent O(3P) atoms at various
photolysis wavelengths between 230 and 308 nm by scanning
the wavelength of the VUV probe laser (band width 0.8
cm1) around the resonance center of 3s3S o – 2p3P2 transition. No obvious variation in the spectral shape was observed.
[15] The O(1D) quantum yields thus obtained in the
wavelength range of 230– 308 nm are shown in Figure 4.
For comparison, the O(1D) quantum yields reported byother groups are also shown in Figure 4. Table 3 lists theO(1D) quantum yield values obtained in this work. Quoted
errors indicate the two standard deviations (2s) of themeasurements, which are due to the standard deviations
associated with the 5– 10 times experimental measurementsof LIF signal intensities of O(3Pj) and the uncertainties inphotolysis laser power measurements with a laser power
meter. It should be noted that the previous studies on thequantum yield measurements in the Hartley band werecarried out mostly around 290 nm. The small number ofmeasurements in the shorter wavelengths may be due to thedifficulty to obtain the photolysis light source that can cover
the wide wavelength range over the Hartley band of O3. In
our present study, we employed the tunable OPO laser

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11 - 5

Table 3. The Quantum Yield Values of O(1D) Formation in the
Hartley Band Photolysis of O3 at 297 ± 2 K as a Function of
Photolysis Wavelength l in nm.
l1D (l)Uncertainty (2s)

230
232
234
236
238
240
242
244
246
248
250
252
254
256
258
260
261.5
262.5
266
267.2
267.5
269
269.8
270
272
274
276
278
280
284
288
292
296

0.910
0.917
0.928
0.906
0.908
0.910
0.885
0.899
0.896
0.914
0.900
0.914
0.921
0.916
0.914
0.905
0.915
0.910
0.919
0.926
0.927
0.922
0.924
0.924
0.923
0.908
0.900
0.894
0.891
0.873
0.879
0.892
0.881

0.019
0.017
0.016
0.022
0.019
0.020
0.025
0.022
0.023
0.019
0.021
0.019
0.016
0.018
0.020
0.020
0.019
0.019
0.017
0.020
0.016
0.017
0.016
0.017
0.017
0.022
0.023
0.025
0.032
0.021
0.011
0.018
0.022

pumped by the third harmonics of the Nd:YAG laser forthe photolysis light source. It could cover the whole wavelength range of our interest in the present study without any
realignment of the laser system. The usage of the combination of a tunable dye laser and a nonlinear crystal for UV
generation requires frequent changes of dye solutions andcrystals to cover the entire range of the Hartley band, whichconsequently reduces the accuracies in the measurements of
the O(1D) quantum yield in the wide wavelength range.

4. Discussion

Figure 4. The quantum yield for O(1D) formation in the
Hartley band photolysis of O3 at 297 ± 2 K as a function ofphotolysis wavelength. For comparison, the yield values
reported by other groups are also shown. A solid curve
indicates the yield values recommended by NASA/JPL
panel [Sander et al., 2000], which are constant (0.95)
between 240 and 300 nm.

4.1. Quantum Yield for O(1D) Formation in the
Hartley Band Photolysis of O3[16] We have measured the wavelength dependence of theO(1D) quantum yield from O3 photolysis at 2-nm intervals
between 230 and 308 nm. As shown in Figure 4, it has beenfound that the values obtained in this work are almost
independent of the photolysis wavelengths ( 0.91). At
248 nm which is the center of the strong absorption of the
Hartley band, the room temperature O(1D) quantum yield
was reported to be 0.91 ± 0.06 by Talukdar et al. [1997] and0.94 ± 0.01 by Greenblatt and Wiesenfeld [1983]. Our
measured value of 1D(248) = 0.914 ± 0.019 is in good
agreement with their results. Taniguchi et al. [2000] measured the photofragment excitation spectrum for O(3P) fromO3 photolysis in the wavelength range of 296– 314 nm andobtained the O(1D) quantum yield values. Talukdar et al.
[1998] reported that the O(1D) quantum yield between 289

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TAKAHASHI ET AL.: YIELD OF O(1D) IN OZONE PHOTOLYSIS

and 305 nm was 0.89 ± 0.02. The present results are in good
agreement with their results. It has also been shown that theresults presented by Trolier and Wiesenfeld [1988] are larger
than those obtained in this work and also than the results ofrecent studies by Talukdar et al. [1998] and Taniguchi et al.
[2000]. Since the O(1D) quantum yields at some wavelengths reported by Trolier and Wiesenfeld [1988] exceed 1
between 285 and 306 nm, they may overestimate thequantum yields of O(1D) in this wavelength region. Cooper
et al. [1993] observed weak 630-nm fluorescence from thespin-forbidden O(1D) ! O(3P) transition in the photolysisof O3 between 221 and 243.5 nm and determined the O(1D)
quantum yields. They indicated the O(1D) quantum yield
was almost constant in this wavelength range. Their values
are close to those obtained in this study, except for 231 nm.
[17] The NASA/JPL panel recommends the constant valueof 0.95 as the quantum yield for O(1D) formation in the
Hartley band photolysis of O3 between 240 and 300 nm foruse in atmospheric modeling [Sander et al., 2000]. For 222 <l < 271 nm, the IUPAC subcommittee [Atkinson et al.,1997] have recommended a constant value (0.87) which is alittle smaller than the values obtained in this study, while
they recommended larger values than ours near 300 nm.
[18] The Hartley band has been assigned to the strongly
allowed 1B2 – 1A1 transition [Hay et al., 1982]. Photoexcitation to the repulsive limb of the excited 1B2 state results inprompt dissociation into O(1D) + O2(1g) products (channel (1)). Surface crossing from the initially prepared 1B2
state to a repulsive (R) state provides O(3P) + O2(X3
g)products (channel (2)). Our experimental results show thatthe channel branching ratio between O(1D) and O(3P)
formation does not strongly depend on the photolysis
wavelength over the Hartley band (Figure 4 and Table 3).
This suggests that the efficiency of the potential switchingfrom the 1B2 state to the R state is almost independent of theexcitation energy.
4.2. Atmospheric Implications[19] Chemical reactions of the O(1D) atoms with trace gas
molecules are key processes to determine the chemical
nature of the Earth’s atmosphere. For instance, the reactionsof O(1D) + N2O and O(1D) + H2O are the direct source forstratospheric NOx and HOx molecules. The atmosphericproduction rates of O(1D) atom from O3 photolysis at several
altitudes, Ptotal(O1D), were calculated using the quantum
yield values for O(1D) formation measured in this study.
Ptotal O1 D ¼

ZZPðlÞdl ¼

FðlÞsðlÞ1D ðlÞdl

ð7Þ

In the equation (7), F(l) is the altitude dependent solar
photon flux as a function of l. The calculations were
performed for the altitudes of 15, 25, and 40 km. The solar
zenith angle was fixed at 40 degree. The numerical data of
the solar photon flux were taken from Finlayson-Pitts andPitts [1999]. The absorption cross sections of O3 were takenfrom Malicet et al. [1995].
[20] In the calculations, for the wavelengths longer than
300 nm, the expression for the O(1D) quantum yield recommended by NASA/JPL [Sander et al., 2000] was used, which
is functions of photolysis wavelength and temperature. At l >300 nm, the photodissociation of the vibrationally and rotationally excited O3 takes place. Even at longer wavelengths

Figure 5. Production rates of O(1D) produced from thephotolysis of O3 as functions of solar wavelength in thestratosphere at altitudes of 25 and 40 km. Solid curvesindicate the results based on the O(1D) quantum yieldvalues obtained in this work, while broken ones are theresults based on the NASA/JPL recommendations [Sander
et al., 2000].
than the channel (1) threshold ( 310 nm) O(1D) atoms areproduced [Ravishanakara et al., 1998; Takahashi et al.,1998]. Since the population of the internally excited O3
molecules is dependent on the temperature, the O(1D)
quantum yield at l > 305 nm changes as a function of thetemperature. The O(1D) formation via the following spinforbidden process takes place at l > 310 nm [Ravishankara
et al., 1998; Takahashi et al., 1998]: O3 þ hn ! O 1 D þ O2 3 gð8Þ[21] It is assumed that the O(1D) quantum yield in the
Hartley band at l < 300 nm has no temperature dependence.
The recent experimental study at 248 nm showed no temperature dependence of the O(1D) quantum yield [Talukdar etal., 1997]. At 305 nm, Takahashi et al. [1998] showed that
the O(1D) quantum yield has a negligible temperaturedependence. Talukdar et al. [1998] also reported that theO(1D) quantum yield between 289 and 305 nm was independent of the temperature (203– 320 K).
[22] Figure 5 shows the relative O(1D) production ratefunctions P(l) in the stratosphere at the altitudes of 25 andTAKAHASHI ET AL.: YIELD OF O(1D) IN OZONE PHOTOLYSIS

ACH

11 - 7

implies a number of model calculations underestimate the O3
concentrations in the upper stratosphere and mesosphere.

5. Conclusion

Figure 6. Calculated percentage change in O(1D) and O3
concentrations for latitude of 40 degree in March as afunction of altitude using the new O(1D) quantum yieldvalues measured in this study, relative to the NASA/JPL
recommendations [Sander et al., 2000].
40 km, using the (1D) quantum yield values obtained in thisstudy and those recommended by NASA/JPL [Sander et al.
2000]. The total O(1D) production rates Ptotal(O1D) calculated with our O(1D) quantum yield data are smaller thanthose with the NASA/JPL recommendation by 1.7, 3.3 and
5.0%, at 15, 25 and 40 km, respectively.
[23] In this study, we have examined the effect of ourO(1D) quantum yield values using a one-dimensional
dynamical-photochemical model, in which all the chemical
reactions related to ozone chemistry are reasonably represented and it is suitable for assessing the impact of our new
O(1D) quantum yield data on stratospheric chemistry. All
chemical schemes are the same with that in the GarciaSolomon two-dimensional (GS-2D) model [e.g., Solomon etal., 1996]. In this study, the model calculations were
performed including 40 chemical species and 120 chemical
reactions with the chemical kinetics and photochemical data
presented by the recent JPL recommendations [DeMore etal., 1997; Sander et al., 2000].
[24] Figure 6 shows the result of the photochemical model
calculations, which indicates the change of the O(1D) and O3
concentrations for latitude of 40 degree in March between
the model runs with our new O(1D) values and the NASA/
JPL recommendations. The steady state O(1D) concentration
becomes smaller by 2 – 6% depending on altitude in thestratosphere. This result is consistent with our evaluation of
the altitudinal changes in the O(1D) production rate as shownin Figure 5. The O3 concentration evaluated with our O(1D)
yield is higher than that done with the NASA/JPL recommendation throughout the stratosphere as shown in Figure 6.
This is due to the changes in the efficiency of the chain
reactions involving HOx, NOx, and ClOx families throughthe lower O(1D) production rate. Our study may contributeto precise assessment of the photochemical O3 budget
including the ‘‘ozone deficit’’ problem [Crutzen, 1997] that[25] The quantum yield value of the O(1D) formation in
the Hartley band photolysis of O3 has been examined as afunction of the wavelength, using the laser flash photolysis
technique with the laser-induced fluorescence detection of
the atomic oxygen fragments. The detailed measurementsby 2-nm interval have been performed for the wide wavelength range of the Hartley band. The measured quantum
yield was almost independent of the photolysis wavelength
between 230 and 305 nm, with the almost constant value of
0.88– 0.93. The results were compared with the previously
reported values and the latest NASA/JPL and IUAPC
recommendation for atmospheric modeling. The relative
production rates of O(1D) from O3 photolysis in the stratosphere have been evaluated. We have shown that theatmospheric O(1D) production rates calculated with theO(1D) quantum yield values obtained in this study aresmaller than those calculated with the latest NASA/JPL
recommendation by 1.7, 3.3 and 5.0%, at the altitudes of 15,
25 and 40 km, respectively. Using the one-dimensional
photochemical model, change of the O3 concentration
between the runs with our new O(1D) yield values andthe NASA/JPL recommendations has also been examined.
The smaller O(1D) production rates are followed by changes
in the efficiency of the chemical chain reactions involving
HOx, NOx, and ClOx, and result in the higher O3 concentrations throughout the stratosphere.

[26] Acknowledgments. This work was supported by a Grant-in-Aid
from the Ministry of Education, Culture, Sports, Science and Technology,
Japan. N. T. thanks the Japan Society for Promotion of Science for a
fellowship for young scientists. The one-dimensional model used in thisstudy was originally offered by Susan Solomon, NOAA Aeronomy
Laboratory. The authors are grateful to Yukari Shibata and Nao Ikeda for
their help on the model calculations.

References
Abe, M., Y. Sato, Y. Inagaki, Y. Matsumi, and M. Kawasaki, Collisional
relaxation of translational energy and fine-structure levels of the O(3Pj)
atom created in the photodissociation of SO2 at 193 nm, J. Chem. Phys.,101, 5647 – 5651, 1994.
Amimoto, S. T., A. P. Force, J. R. Wiesenfeld, and R. H. Young, Direct
observation of O(3Pj) in the photolysis of O3 at 248 nm, J. Chem. Phys.,
73, 1244 – 1247, 1980.
Atkinson, R., D. L. Baulch, R. A. Cox, R. F. Hampson Jr, J. A. Kerr, M. J.
Rossi, and J. Troe, Evaluated kinetic and photochemical data for atmospheric chemistry: Supplement VI, J. Phys. Chem. Ref., 1329 – 1499,
1997.
Ball, S. M., G. Hancock, I. J. Murphy, and S. P. Rayner, The relative
quantum yield of O2(a1g) from the photolysis of ozone in the wavelength range 270 nm < l < 329 nm, Geophys. Res. Lett., 20, 2063 – 2066,
1993.
Brasseur, G. P., J. J. Orlando, and G. S. Tyndall, Atmospheric Chemistry
and Global Change, Oxford Univ. Press, New York, 1999.
Brock, J. C., and R. T. Watson, Ozone photolysis: Determination of O(3P)
quantum yield at 266 nm, Chem. Phys. Lett., 71, 371 – 375, 1980.
Cooper, I. A., P. J. Neill, and J. R. Wiesenfeld, Relative quantum yield ofO(1D2) following ozone photolysis between 221 and 243.5 nm, J. Geophys. Res., 98, 12,795 – 12,800, 1993.
Crutzen, P. J., Mesospheric mysteries, Science, 277, 151 – 152, 1997.
DeMore, W. P., S. P. Sander, C. J. Howard, A. R. Ravishankara, D. M.
Golden, C. E. Kolb, R. F. Hampson, M. J. Kurylo, and M. J. Molina,
Chemical kinetics and photochemical data for use in stratospheric modeling, JPL Publ., 97-4, Eval. 12, Jet Propul. Lab., Pasadena, Calif., 1997.

ACH

11 - 8TAKAHASHI ET AL.: YIELD OF O(1D) IN OZONE PHOTOLYSIS

Fairchild, C. E., E. J. Stone, and G. M. Lawrence, Photofragment spectroscopy of ozone in the uv region 270 – 310 nm and at 600 nm, J. Chem.
Phys., 69, 3632 – 3638, 1978.
Finlayson-Pitts, B. J., and J. N. Pitts Jr., Chemistry of the Upper and Lower
Atmosphere: Theory, Experiments, and Applications, Academic, San
Diego, Calif., 1999.
Greenblatt, G. D., and J. R. Wiesenfeld, Time-resolved fluorescence studiesof O(1D2) yields in the photodissociation of O3 at 248 and 308 nm,
J. Chem. Phys., 78, 4924 – 4928, 1983.
Hay, P. J., R. T. Pack, R. B. Walker, and E. J. Heller, Photodissociation ofozone in the Hartley band: Exploratory potential energy surfaces andmolecular dynamics, J. Phys. Chem., 86, 862 – 865, 1982.
Lee, L. C., G. Black, R. L. Sharpless, and T. G. Slanger, O(1S ) yield fromO3 photodissociation at 1700 – 2400 Å, J. Chem. Phys., 73, 256 – 258,
1980.
Malicet, J., D. Daumont, J. Charbonnier, C. Parisse, A. Chakir, and J. Brion,
Ozone UV spectroscopy, II, Absorption cross-sections and temperaturedependence, J. Atmos. Chem., 21, 263 – 273, 1995.
Matsumi, Y., F. J. Comes, G. Hancock, A. Hofzumahaus, A. J. Hynes, M.
Kawasaki, and A. R. Ravishankara, Quantum yields for production ofO(1D) in the ultraviolet photolysis of ozone: Recommendation basedon evaluation of laboratory data, J. Geophys. Res., 107(D3), 4024,
doi:10.1029/2001JD000510, 2002.
Okabe, H., Photochemistry of Small Molecules, Wiley-Interscience, New
York, 1978.
Ravishanakara, A. R., G. Hancock, M. Kawasaki, and Y. Matsumi, Photochemistry of Ozone: Surprises and Recent Lessons, Science, 280, 60 – 61,
1998.
Sander, S. P., R. R. Friedel, R. E. Huie, M. J. Kurylo, C. E. Kolb, D.M.
Golden, A. R. Ravishankara, and M. J. Molina, Chemical Kinetics andPhotochemical Data for Stratospheric Modeling, JPL Publ. 00-3, JPL,
Pasadena, Calif., 2000.
Solomon, S., R. W. Portmann, R. R. Garcia, L. W. Thomason, L. R. Poole,and M. P. McCormick, The role of aerosol variations in anthropogenic
ozone depletion at northern midlatitudes, J. Geophys. Res., 101, 6713 –
6727, 1996.
Sparks, R. K., L. R. Carlson, K. Shobatake, M. L. Kowalczyk, and Y. T.
Lee, Ozone photolysis: A determination of the electronic and vibrational
state distributions of primary products, J. Chem. Phys., 72, 1401 – 1402,
1980.
Stief, L. J., W. A. Payne, and R. B. Klemm, A flash photolysis-resonancefluorescence study of the formation of O(1D) in the photolysis of waterand the reaction of O(1D) with H2, Ar, and He, J. Chem. Phys., 62,
4000 – 4008, 1975.
Takahashi, K., Y. Matsumi, and M. Kawasaki, Photodissociation processesof ozone in the Huggins band at 308 – 326 nm, J. Chem. Phys., 100,
4084 – 4089, 1996a.
Takahashi, K., M. Kishigami, Y. Matsumi, M. Kawasaki, and A. J. Orr-

Ewing, Observation of the spin-forbidden O(1D) + O2(X3g ) channel inthe 317 – 327 nm photolysis of ozone, J. Chem. Phys., 105, 5290 – 5293,
1996b.
Takahashi, K., M. Kishigami, N. Taniguchi, Y. Matsumi, and M. Kawasaki,
Photofragment excitation spectrum for O(1D) from the photodissociationof jet-cooled ozone in the wavelength range 305 – 329 nm, J. Chem.
Phys., 106, 6390 – 6397, 1997.
Takahashi, K., N. Taniguchi, Y. Matsumi, M. Kawasaki, and M. N. R.
Ashfold, Wavelength and temperature dependence of the absoluteO(1D) production yield from the 305 – 329 nm photodissociation ofozone, J. Chem. Phys., 108, 7161 – 7172, 1998.
Talukdar, R. K., M. K. Gilles, F. Battin-Leclerc, A. R. Ravishankara, J.-M.
Fracheboud, J. J. Orlando, and G. S. Tyndall, Photolysis of ozone at 308
and 248 nm: Quantum yield of O(1D) as a function of temperature,
Geophys. Res. Lett., 24, 1091 – 1094, 1997.
Talukdar, R. K., C. A. Langfellow, M. K. Gilles, and A. R. Ravishankara,
Quantum yields of O(1D) in the photolysis of ozone between 289 and 329
nm as a function of temperature, Geophys. Res. Lett., 25, 143 – 146, 1998.
Taniguchi, N., K. Takahashi, and Y. Matsumi, Photodissociation of O3
around 309 nm, J. Phys. Chem., A104, 8936 – 8944, 2000.
Trolier, M., and J. R. Wiesenfeld, Relative quantum yield of O(1D2) following ozone photolysis between 275 and 325 nm, J. Geophys. Res., 93,7119 – 7124, 1988.
Turnipseed, A. A., G. L. Vaghijiani, T. Gierczak, J. E. Thompson, and A. R.
Ravishankara, The photochemistry of ozone at 193 nm and 222 nm,
J. Chem. Phys., 95, 3244 – 3251, 1991.
Valentini, J. J., D. R. Gerrty, D. L. Phillips, J.-C. Nieh, and K. D. Tabor,
CARS spectroscopy of O2(1g) from the Hartley band photodissociationof O3: Dynamics of the dissociation, J. Chem. Phys., 86, 6745 – 6756,
1987.
Wayne, R. P., Chemistry of Atmospheres, 3rd edition, Oxford Univ. Press,
New York, 2000.
Wine, P. H., and A. R. Ravishankara, O3 photolysis at 248 nm and O(1D2)
quenching by H2O, CH4, H2, and N2O: O(3Pj) yields, Chem. Phys., 69,
365 – 373, 1982.

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S. Hayashi, Y. Matsumi, and K. Takahashi, Solar-Terrestrial Environment
Laboratory and Graduate School of Science, Nagoya University, Honohara
3-13, Toyokawa, Aichi, 442-8507, Japan. (matsumi@stelab.nagoya-u.ac.jp;
kent@stelab.nagoya-u.ac.jp)
S. Hayashida, Faculty of Science, Nara Women’s University, Kita-uoya
Nishi-machi, Nara, 630-8506, Japan. (sachiko@ics.nara-wu.ac.jp)
N. Taniguchi, Department of Molecular Engineering, Kyoto University,
Yoshidahonmachi, Sakyou-ku, Kyoto, 606-8501, Japan. (ntanig@ip.media.
kyoto-u.ac.jp)