Kinetics of OH radical reactions with a series of ethers

The rate constants for the reactions of OH with dimethyl ether (k₁), diethyl ether (k₂), di-n-propyl ether (k₃), di-isopropyl ether (k₄), and di-n-butyl ether (k₅) have been measured over the temperature range 230–372 K using the pulsed laser photolysis-laser induced fluorescence (PLP-LIF) technique. The temperature dependence of k₁,k₄, can be expressed in the Arrhenius plots form: k₁ = (6.30 ± 0.10) × 10^?12 exp[?(234 ± 34)/T] and k₄ = (4.13 ± 0.10) × 10^?12 exp[(274 ± 26)/T]. The Arrhenius plots for k₂,k₃, and k₅, were curved and they were fitted to the three parameter expressions: k₂ = (1.02 ± 0.08) × 10^?17 T² exp[(797 ± 24)/T], k₃ = (1.84 ± 0.23) × 10^?17T² exp[(767 ± 34)/T], and k₅ = (6.29 ± 0.74) × 10^?18T² exp[(1164 ± 34)/T]. The values at 298 K are (2.82 ± 0.21) × 10^?12, (1.36 ± 0.11) × 10^?11,(2.17 ± 0.16) × 10^?11, (1.02 ± 0.10) × 10^?11, and (2.69 ± 0.22) × 10^?11 for k₁, k₂, k₃, k₄, and k₅, respectively, (in cm³ molecule^?1 s^?1). These results are compared to the literature data. © 1995 John Wiley & Sons, Inc.     

Kinetics of the reactions of pinonaldehyde with OH radicals and with Cl atoms

The rate constant for the reaction of OH radicals with pinonaldehyde has been measured at 293 ± 6 K using the relative rate method in the laboratory in Wuppertal (Germany) using photolytic sources for the production of OH radicals and in the EUPHORE smog chamber facility in Valencia (Spain) using the in situ ozonolysis of 2,3‐dimethyl‐2‐butene as a dark source of OH radicals. In all the experiments pinonaldehyde and the reference compounds were monitored by FTIR spectroscopy, and in addition in the EUPHORE smog chamber the decay of pinonaldehyde was monitored by the HPLC/DNPH method and the reference compound by GC/FID. The results from all the different series of experiments were in good agreement and lead to an average value of k(pinonaldehyde + OH) = (4.0 ± 1.0) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹. This result lead to steady‐state estimates of atmospheric pinonaldehyde concentrations in the ppbV range (1 ppbV ≈ 2.5 × 10¹⁰ molecule cm⁻³ at 298 K and 1 atm) in regions with substantial α‐pinene emission. It also implies that atmospheric sinks of pinonaldehyde by reaction with OH radicals could be half as important as its photolysis. The rate constant of the reaction of pinonaldehyde with Cl atoms has been measured for the first time. Relative rate measurements lead to a value of k(pinonaldehyde + Cl) = (2.4 ± 1.4) × 10⁻¹⁰ cm³ molecule⁻¹ s⁻¹. In contrast to previous studies which suggested enhanced kinetic reactivity for pinonaldehyde compared to other aldehydes, the results from both the OH‐ and Cl‐initiated oxidation of pinonaldehyde in the present work are in line with predictions using structure‐activity relationships. © 1999 John Wiley & Sons, Inc., Int J Chem Kinet 31: 291–301, 1999     

Kinetics of the OH + ClOOCl and OH + Cl2O reactions: experiment and theory

The rate coefficients for the reactions OH + ClOOCl --> HOCl + ClOO (eq 5) and OH + Cl2O --> HOCl + ClO (eq 6) were measured using a fast flow reactor coupled with molecular beam quadrupole mass spectrometry. OH was detected using resonance fluorescence at 309 nm. The measured Arrhenius expressions for these reactions are k5 = (6.0 +/- 3.5) x 10(-13) exp((670 +/- 230)/T) cm(3) molecule(-1) s(-1) and k6 = (5.1 +/- 1.5) x 10(-12) exp((100 +/- 92)/T) cm(3) molecule(-1) s(-1), respectively, where the uncertainties are reported at the 2sigma level. Investigation of the OH + ClOOCl potential energy surface using high level ab initio calculations indicates that the reaction occurs via a chlorine abstraction from ClOOCl by the OH radical. The lowest energy pathway is calculated to proceed through a weak ClOOCl-OH prereactive complex that is bound by 2.6 kcal mol(-1) and leads to ClOO and HOCl products. The transition state to product formation is calculated to be 0.59 kcal mol(-1) above the reactant energy level. Inclusion of the OH + ClOOCl rate data into an atmospheric model indicates that this reaction contributes more than 15% to ClOOCl loss during twilight conditions in the Arctic stratosphere. Reducing the rate of ClOOCl photolysis, as indicated by a recent re-examination of the ClOOCl UV absorption spectrum, increases the contribution of the OH + ClOOCl reaction to polar stratospheric loss of ClOOCl.     

Kinetics of OH reactions with aliphatic thiols

The kinetics of OH reactions with 1–4 carbon aliphatic thiols have been investigated over the temperature range 252–430 K. OH radicals were produced by flash photolysis of water vapor at λ > 165 nm and detected by time-resolved resonance fluorescence spectroscopy. All thiols investigated react with OH at nearly the same rate; k(298 K) = 3.2–4.6 × 10^?11 cm³ molecule^?1 s^?1, -E_act = 0.6–1.0 kcal/mol, A = 0.6–1.2 × 10^?11 cm³ molecule^?1 s^?1. CH₃SH and CH₃SD react with OH at identical rates over the entire temperature range investigated. We conclude that the dominant reaction pathway is addition to the sulfur atom.     

Kinetics of the reactions of OH with alkanes

The rate coefficients for the reactions of OH with ethane (k₁), propane (k₂), n-butane (k₃), iso-butane (k₄), and n-pentane (k₅) have been measured over the temperature range 212–380 K using the pulsed photolysis-laser induced fluorescence (PP-LIF) technique. The 298 K values are (2.43±0.20) × 10^?13, (1.11 ± 0.08) × 10^?12, (2.46 ± 0.15) × 10^?12, (2.06 ± 0.14) × 10^?12, and (4.10 ± 0.26) × 10^?12 cm³ molecule^?1 s^?1 for k₁, k₂, k₃, k₄, and k₅, respectively. The temperature dependence of k₁ and k₂ can be expressed in the Arrhenius form: k₁ = (1.03 ± 0.07) × 10^?11 exp[?(1110 ± 40)/T] and k₂ = (1.01 ± 0.08) × 10^?11 exp[?(660 ± 50)/T]. The Arrhenius plots for k₃ – k₅ were clearly curved and they were fit to three parameter expressions: k₃ = (2.04 ± 0.05) × 10^?17 T² exp[(85 ± 10)/T] k₄ = (9.32 ± 0.26) × 10^?18 T² exp[(275 ± 20)/T]; and k₅ = (3.13 ± 0.25) × 10^?17 T² exp[(115 ± 30)/T]. The units of all rate constants are cm³ molecule^?1 s^?1 and the quoted uncertainties are at the 95% confidence level and include estimated systematic errors. The present measurements are in excellent agreement with previous studies and the best values for atmospheric calculations are recommended. © 1994 John Wiley & Sons, Inc.     

Kinetics of the reactions of hydroxyl radical with aliphatic aldehydes

Rate coefficients for OH reactions with the 2–5 carbon aliphatic aldehydes have been measured under pseudo first-order conditions in OH. OH was generated by flash photolysis of H₂O at wavelengths greater than 165 nm and its concentration monitored using time-resolved resonance fluorescence spectroscopy. Two reactions were studied only at 298 K while five reactions were studied over the temperature range 250–425 K; negative activation energies were observed for all five reactions. Aldehyde reactivity toward OH is nearly independent of the identity of the hydrocarbon side chain. Our results are compared with those obtained in previous studies of OH-aldehyde reaction kinetics and their mechanistic implications are discussed.     

Kinetics of OH reactions with furan,thiophene, and tetrahydrothiophene

The kinetics of OH reactions with furan (k₁), thiophene (k₂), and tetrahydrothiophene (k₃), have been investigated over the temperature range 254–425 K. OH radicals were produced by flash photolysis of water vapor at λ > 165 nm and detected by timeresolved resonance fluorescence spectroscopy. The following Arrhenius expressions adequately describe the measured rate constants as a function of temperature (units are cm³ molecule^?1 S^?1): k₁ = (1.33 ± 0.29) × 10^?11 exp[(333 ± 67)/T], k₂ = (3.20 ± 0.70) × 10^?12 exp[(325 ± 71)/T], k₃ = (1.13 ± 0.35) × 10^?11 exp[(166 ± 97)/T]. The results are compared with previous investigations and their implications regarding reaction mechanisms and atmospheric residence times are discussed.     

Kinetics of the reactions of CH3O with Cl and CIO

The kinetics of the reactions CH₃O + Cl → H₂CO + HCl (1) and CH₃O + ClO → H₂CO + HOCl (2) have been studied using the discharge-flow techniques. CH₃O was monitored by laser-induced fluorescence, whereas mass spectrometry was used for the detection or titration of other species. The rate constants obtained at 298 K are: k₁ = (1.9 ± 0.4) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ and k₂ = (2.3 ± 0.3) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹. These data are useful to interpret the results of the studies of the reactions of CH₃O₂ with Cl and ClO which, at least partly, produce CH₃O radicals. © 1996 John Wiley & Sons, Inc.     

Kinetics of the reactions of O3 and OH radicals with a series of dialkenes and trialkenes at 294 ± 2 K

Rate constants for the gas phase reactions of O₃ and OH radicals with 1,3-cycloheptadiene, 1,3,5-cycloheptatriene, and cis- and trans-1,3,5-hexatriene and also of O₃ with cis-2,trans-4-hexadiene and trans -2,trans -4-hexadiene have been determined at 294 ± 2 K. The rate constants determined for reaction with O₃ were (in cm³ molecule^-1s^?1 units): 1,3-cycloheptadiene, (1.56 ± 0.21) × 10^-16; 1,3,5-cycloheptatriene, (5.39 ± 0.78) × 10^?17; 1,3,5-hexatriene, (2.62 ± 0.34) × 10^?17; cis?2,trans-4-hexadiene, (3.14 ± 0.34) × 10^?16; and trans ?2, trans -4-hexadiene, (3.74 ± 0.61) × 10^?16; with the cis- and trans-1,3,5-hexatriene isomers reacting with essentially identical rate constants. The rate constants determined for reaction with OH radicals were (in cm³ molecule^?1 s^?1 units): 1,3-cycloheptadiene, (1.31 ± 0.04) × 10^?10; 1,3,5-cycloheptatriene, (9.12 × 0.23) × 10^?11; cis-1,3,5-hexatriene, (1.04 ± 0.07) × 10^?10; and trans 1,3,5-hexatriene, (1.04 ± 0.17) × 10^?10. These data, which are the first reported values for these di- and tri-alkenes, are discussed in the context of previously determined O₃ and OH radical rate constants for alkenes and cycloalkenes.     

Kinetics and products of the reactions of selected diols with the OH radical

Using a relative rate method, rate constants have been measured at 296 ± 2 K for the gas‐phase reactions of OH radicals with 1,2‐butanediol, 2,3‐butanediol, 1,3‐butanediol, and 2‐methyl‐2,4‐pentanediol, with rate constants (in units of 10^?12 cm³ molecule^?1 s^?1) of 27.0 ± 5.6, 23.6 ± 6.3, 33.2 ± 6.8, and 27.7 ± 6.1, respectively, where the error limits include the estimated overall uncertainty of ±20% in the rate constant for the reference compound. Gas chromatographic analyses showed the formation of 1‐hydroxy‐2‐butanone from 1,2‐butanediol, 3‐hydroxy‐2‐butanone from 2,3‐butanediol, 1‐hydroxy‐3‐butanone from 1,3‐butanediol, and 4‐hydroxy‐4‐methyl‐2‐pentanone from 2‐methyl‐2,4‐pentanediol, with formation yields of 0.66 ± 0.11, 0.89 ± 0.09, 0.50 ± 0.09, and 0.47 ± 0.09, respectively, where the indicated errors are the estimated overall uncertainties. Pathways for the formation of these products are presented, together with a comparison of the measured and estimated rate constants and product yields. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 310–316, 2001     

Gas‐phase rate coefficients for a series of alkyl cyclohexanes with OH radicals and Cl atoms

The rate coefficients of the reactions of OH radicals and Cl atoms with three alkylcyclohexanes compounds, methylcyclohexane (MCH), trans‐1,4‐dimethylcyclohexane (DCH), and ethylcyclohexane (ECH) have been investigated at (293 ± 1) K and 1000 mbar of air using relative rate methods. A majority of the experiments were performed in the Highly Instrumented Reactor for Atmospheric Chemistry (HIRAC), a stainless steel chamber using in situ FTIR analysis and online gas chromatography with flame ionization detection (GC‐FID) detection to monitor the decay of the alkylcyclohexanes and the reference compounds. The studies were undertaken to provide kinetic data for calibrations of radical detection techniques in HIRAC. The following rate coefficients (in cm³ molecule⁻¹ s⁻¹) were obtained for Cl reactions: k_(Cl+MCH) = (3.51 ± 0.37) × 10^–10, k_(Cl+DCH) = (3.63 ± 0.38) × 10⁻¹⁰, k_(Cl+ECH) = (3.88 ± 0.41) × 10⁻¹⁰, and for the reactions with OH radicals: k_(OH+MCH) = (9.5 ± 1.3) × 10^–12, k_(OH+DCH) = (12.1 ± 2.2) × 10⁻¹², k_(OH+ECH) = (11.8 ± 2.0) × 10⁻¹². Errors are a combination of statistical errors in the relative rate ratio (2σ) and the error in the reference rate coefficient. Checks for possible systematic errors were made by the use of two reference compounds, two different measurement techniques, and also three different sources of OH were employed in this study: photolysis of CH₃ONO with black lamps, photolysis of H₂O₂ at 254 nm, and nonphotolytic trans‐2‐butene ozonolysis. For DCH, some direct laser flash photolysis studies were also undertaken, producing results in good agreement with the relative rate measurements. Additionally, temperature‐dependent rate coefficient investigations were performed for the reaction of methylcyclohexane with the OH radical over the range 273‐343 K using the relative rate method; the resulting recommended Arrhenius expression is k_{(OH + MCH)} = (1.85 ± 0.27) × 10^–11 exp((–1.62 ± 0.16) kJ mol⁻¹/RT) cm³ molecule⁻¹ s⁻¹. The kinetic data are discussed in terms of OH and Cl reactivity trends, and comparisons are made with the existing literature values and with rate coefficients from structure‐activity relationship methods. This is the first study on the rate coefficient determination of the reaction of ECH with OH radicals and chlorine atoms, respectively.     

Rate constants for reactions of OH radicals with a series of asymmetrical ethers and tert-Butyl alcohol

Absolute rate constants for the reactions of OH radicals with butyl ethyl ether (k₁), methyl tert-butyl ether (k₂), ethyl tert-butyl ether (k₃) tert-amyl methyl ether (k₄) and tert-butyl alcohol (k₅) have been measured over the temperature range 230–372 K using a pulsed laser photolysis-laser induced fluorescence (PLP-LIF) technique. The temperature dependence of k₁ − k₅ when expressed in Arrhenius form gave: k₁ = (6.59 ± 0.66) × 10 ⁻¹² exp|(362 ± 60)/T|, k₂ = (5.03 ± 0.27) × 10⁻¹² exp|&minus(133 ± 30)/T|, k₃ = (4.40 ± 0.24) × 10⁻¹² exp|(210 ± 37)/T|,k⁴ = (4.7 ± 0.7) × 10⁻¹² exp|(82 ± 85)/T|, and k₅ = (2.66 ± 0.48) × 10⁻¹² exp| −(270 ± 130)/T|. However, the Arrhenius plots for k₁–k₅, were slightly curved and are best fitted by the three parameter fits which are given in the article. The room temperature values of k₁, k₂, k₃, k₄, and k₅ are (2.08 ± 0.23) × 10⁻¹¹, (3.13 ± 0.36) × 10⁻¹², (8.80 ± 0.50) × 10⁻¹², (6.28 ± 0.45) × 10⁻¹², and (1.08 ± 0.10) × 10⁻¹², respectively, in cm³ molecule⁻¹ s⁻¹. © 1996 John Wiley & Sons, Inc.     

Rate constants for the reactions of O3 and OH radicals with a series of alkynes

Rate constants for the reactions of O₃ and OH radicals with acetylene, propyne, and 1-butyne have been determined at room temperature. The rate constants obtained at 294 ± 2 K for the reactions of O₃ with acetylene, propyne, and 1-butyne were (7.8 ± 1.2) × 10^?21 cm³/molecule · s, (1.43 ± 0.15) × 10^?20 cm³/molecule · s, and (1.97 ± 0.26) × 10^?20 cm³/molecule · s, respectively. The rate constants at 298 ± 2 K and atmospheric pressure for the reactions with the OH radical, relative to a rate constant for the reaction of OH radicals with cyclohexane of 7.57 × 10^?12 cm³/molecule · s, were determined to be (8.8 ± 1.4) × 10^?13 cm³/molecule · s, (6.21 ± 0.31) × 10^?12 cm³/molecule · s, and (8.25 ± 0.23) × 10^?12 cm³/molecule · s for acetylene, propyne, and 1-butyne, respectively. These data are discussed and compared with the available literature rate constants.     

Rate constants and atmospheric lifetimes for the reactions of OH radicals and Cl atoms with haloalkanes

Rate constants for the reactions of Cl atoms and OH radicals with haloalkanes were measured using the relative rate technique. From these values the atmospheric lifetimes of the organics with respect to Cl atoms and OH radicals were calculated. Cl atoms were produced by the photolysis of chlorine gas, and photolysis of methyl nitrite was the source of OH radicals. The rate constants were measured for a series of brominated and chlorinated alkanes for which measurements have not yet been reported excepting: k(Cl + 1-chloropropane) and k(OH + 1-chloropropane, 2-chloropropane, and bromoethane). The organics studied were 1-chloropropane, 2-chloropropane, 1,3 dichloropropane, 2-chloro 2methylpropane, bromoethane, 1-bromopropane, 2-bromopropane, 1-bromobutane, 1-bromopentane, and 1-bromohexane. Cl atom reactions were measured at 298 K, the OH radical reactions were measured at temperatures between 298–308 K. © 1993 John Wiley & Sons, Inc.     

Matrix isolation study of the reactions of CrO2Cl2 with a series of silanes

The reactions between CrO2Cl2 and a series of silanes have been investigated using matrix isolation infrared spectroscopy. Twin-jet codeposition of the two reagents into argon matrices at 14 K followed by irradiation with light of lambda > 300 nm led to the growth of a number of new bands. These have been assigned to the appropriate silanol species formed by oxygen insertion into the Si-H bond, strongly complexed to CrCl2O. The structures and vibrational frequencies of these complexes have been characterized by high-level theoretical calculations. These calculations also support the relative preference for the insertion reaction compared to other possible pathways. Merged-jet codeposition of SiH2Cl2 with CrO2Cl2 at 200 degrees C also led to the formation of the free silanol, HSiCl2OH.     

硝酸异丙酯与Cl原子、OH和NO3自由基反应的机理及动力学

采用CCSD(T)//M06-2X/6-311++G(d,p)方法, 结合传统过渡态理论, 研究了硝酸异丙酯与Cl原子、 OH及NO₃自由基的反应机理和动力学. 两个反应物单体首先形成氢键复合物, 随后X(X=Cl原子、 OH和NO₃自由基)提取硝酸异丙酯中叔碳的α-H原子或甲基的β-H原子, 室温下, 以X提取α-H原子为主. 反应的主要历程为 Cl原子(OH或NO₃自由基)提取(CH₃)₂CHONO₂的α-H原子, 生成HCl(H₂O或HNO₃)分子和(CH₃)₂CONO₂自由基, 后者分解为丙酮和NO₂. 结果表明, 在200~500 K温度范围内, 随着温度的升高, 丙酮和NO₂的产率降低; 在室温下, 硝酸异丙酯与Cl原子、 OH和NO₃自由基反应的速率常数分别为3.933×10^-11, 1.182×10^-13和7.134×10^-19 cm³·molecule^-1·s^-1. 计算所得硝酸异丙酯与OH自由基反应的动力学数据与实验结论一致.     

Atmospheric chemistry of CCl2FCH2CF3 (HCFC-234fb): Kinetics and mechanism of reactions with Cl atoms and OH radicals

The atmospheric chemistry of CCl₂FCH₂CF₃ (HFCF-234fb) was examined using FT-IR/relative-rate methods. Hydroxyl radical and chlorine atom rate coefficients of k(CCl₂FCH₂CF₃+OH)= (2.9 ± 0.8) × 10⁻¹⁵ cm³ molecule^–1 s^–1 and k(CCl₂FCH₂CF₃+Cl)= (2.3 ± 0.6) × 10⁻¹⁷ cm³ molecule^–1 s^–1 were determined at 297 ± 2 K. The OH rate coefficient determined here is two times higher than the previous literature value. The atmospheric lifetime for CCl₂FCH₂CF₃ with respect to reaction with OH radicals is approximately 21 years using the OH rate coefficient determined in this work, estimated Arrhenius parameters and scaling it to the atmospheric lifetime of CH₃CCl₃. The chlorine atom initiated oxidation of CCl₂FCH₂CF₃ gives C(O)F₂ and C(O)ClF as stable secondary products. The halogenated carbon balance is close to 80% in our system. The integrated IR absorption cross-section for CCl₂FCH₂CF₃ is 1.87 × 10⁻¹⁶ cm molecule⁻¹ (600–1600 cm⁻¹) and the radiative efficiency was calculated to 0.26 W m⁻² ppb¹. A 100-year Global Warming Potential (GWP) of 1460 was determined, accounting for an estimated stratospheric lifetime of 58 years and using a lifetime-corrected radiative efficiency estimation.     

Rate constants for the gas‐phase reactions of Cl atoms with a series of ethers

The laser photolysis–resonance fluorescence technique has been used to determine the absolute rate coefficient for the Cl atom reaction with a series of ethers, at room temperature (298 ± 2) K and in the pressure range 15–60 Torr. The rate coefficients obtained (in units of cm³ molecule⁻¹ s⁻¹) are dimethyl ether (1.3 ± 0.2) × 10⁻¹⁰, diethyl ether (2.5 ± 0.3) × 10⁻¹⁰, di‐n‐propyl ether (3.6 ± 0.4) × 10⁻¹⁰, di‐n‐butyl ether (4.5 ± 0.5) × 10⁻¹⁰, di‐isopropyl ether (1.6 ± 0.2) × 10⁻¹⁰, methyl tert‐butyl ether (1.4 ± 0.2) × 10⁻¹⁰, and ethyl tert‐butyl ether (1.5 ± 0.2) × 10⁻¹⁰. The results are discussed in terms of structure–reactivity relationship. © 2000 John Wiley & Sons, Inc. Int J Chem Kinet 32: 105–110, 2000     

Kinetics of hydrogen abstraction reactions of butene isomers by OH radical

The rate coefficients of H-abstraction reactions of butene isomers by the OH radical were determined by both canonical variational transition-state theory and transition-state theory, with potential energy surfaces calculated at the CCSD(T)/6-311++G(d,p)//BH&HLYP/6-311G(d,p) level and CCSD(T)/6-311++G(d,p)//BH&HLYP/cc-pVTZ level and quantum mechanical tunneling effect corrected by either the small-curvature tunneling method or the Eckart method. While 1-butene contains allylic, vinylic, and alkyl hydrogens that can be abstracted to form different butene radicals, results reveal that s-allylic H-abstraction channels have low and broad energy barriers, and they are the most dominant channels which can occur via direct and indirect H-abstraction channels. For the indirect H-abstraction s-allylic channel, the reaction can proceed via forming two van der Waals prereactive complexes with energies that are 2.7-2.8 kcal mol(-1) lower than that of the entrance channel at 0 K. Assuming that neither mixing nor crossover occurs between different reaction pathways, the overall rate coefficient was calculated by summing the rate coefficients of the s-allyic, methyl, and vinyl H-abstraction paths and found to agree well with the experimentally measured OH disappearance rate. Furthermore, the rate coefficients of p-allylic H abstraction of cis-2-butene, trans-2-butene, and isobutene by the OH radical were also determined at 300-1500 K, with results analyzed and compared with available experimental data.     

Kinetics of the reactions of Cl*(2P(1/2)) and Cl(2P(3/2)) atoms with CH3OH, C2H5OH, n-C3H7OH, and i-C3H7OH at 295 K

The title reactions were studied using laser flash photolysis/laser-induced-fluorescence (FP-LIF) techniques. The two spin-orbit states, Cl*(2P(1/2)) and Cl(2P(3/2)), were detected using LIF at 135.2 and 134.7 nm, respectively. Measured reaction rate constants were as follows (units of cm3 molecule(-1) s(-1)): k(Cl(2P(3/2))+CH3OH) = (5.35 +/- 0.24) x 10(-11), k(Cl(2P(3/2))+C2H5OH) = (9.50 +/- 0.85) x 10(-11), k(Cl(2P(3/2))+n-C3H7OH) = (1.71 +/- 0.11) x 10(-10), and k(Cl(2P(3/2))+i-C3H7OH) = (9.11 +/- 0.60) x 10(-11). Measured rate constants for total removal of Cl*(2P(1/2)) in collisions with CH3OH, C2H5OH, n-C3H7OH, and i-C3H7OH were (1.95 +/- 0.13) x 10(-10), (2.48 +/- 0.18) x 10(-10), (3.13 +/- 0.18) x 10(-10), and (2.84 +/- 0.16) x 10(-10), respectively; quoted errors are two-standard deviations. Although spin-orbit excited Cl*(2P(1/2)) atoms have 2.52 kcal/mol more energy than Cl(2P(3/2)), the rates of chemical reaction of Cl*(2P(1/2)) with CH3OH, C2H5OH, n-C3H7OH, and i-C3H7OH are only 60-90% of the corresponding Cl(2P(3/2)) atom reactions. Under ambient conditions spin-orbit excited Cl* atoms are responsible for 0.5%, 0.5%, 0.4%, and 0.7% of the observed reactivity of thermalized Cl atoms toward CH3OH, C2H5OH, n-C3H7OH, and i-C3H7OH, respectively.