Atmospheric chemistry of HFC-143a: Spectrokinetic investigation of the CF3CH2O2• radical, its reactions with NO and NO2, and the fate of CF3CH2O

Ole J. Nielsen; Elisabeth Gamborg; Jens Sehested; Timothy J. Wellington; Michael D. Hurley

Atmospheric chemistry of HFC-143a: Spectrokinetic investigation of the CF₃CH₂O₂^• radical, its reactions with NO and NO₂, and the fate of CF₃CH₂O

Ole J. Nielsen^*, Elisabeth Gamborg, Jens Sehested, Timothy J. Wellington, Michael D. Hurley

^*Corresponding author af dette arbejde

26 Citationer (Scopus)

Abstract

The ultraviolet absorption spectrum of CF₃CH₂O₂ radicals, the kinetics of their self-reaction, and their reactions with NO and NO₂ have been studied in the gas phase at 296 K using a pulse radiolysis technique. A long path-length Fourier transform infrared technique was used to study the fate of CF₃CH₂O radicals. Absorption cross sections were quantified over the wavelength range 220-300 nm. At 250 nm, σ(CF₃CH₂O₂) = (2.73 ± 0.31) × 10^-18 molecule^-1. By monitoring the rate of NO₂ formation, k₄ = (1.2 ± 0.3) 10^-11 cm³ molecule^-1 s^-1 was found for the reaction of CF₃CH₂O₂ radical with NO. The reaction of CF₃CH₂O₂ radicals with NO gives CF₃CH₂O radicals. In the atmosphere, >99.3% of the CF₃CH₂O radicals react with O₂ to give CF₃CHO. By monitoring the rate of NO₂ decay, k₅ = (5.8 ± 1.1) × 10^-12 cm³ molecule^-1 s^-1 was found for the reaction of CF₃CH₂O₂ radical with NO₂. The results are discussed with respect to the atmospheric chemistry of CF₃CH₃ (HFC-143a). As a part of the present work, relative rate techniques were used to measure the following rate constants: (2.6 ± 0.7) × 10^-12 and (2.0 ± 0.5) × 10^-12 for the reaction of F atoms with CF₃CH₃, (5.5 ± 0.3) × 10^-11 for the reaction of F atoms with CF₃CH₂OH, and (3.6 ± 0.2) × 10^-17 for the reaction with Cl atoms with CF₃CH₃ (units of cm³ molecule^-1 s^-1).

Originalsprog	Engelsk
Tidsskrift	Journal of Physical Chemistry
Vol/bind	98
Udgave nummer	38
Sider (fra-til)	9518-9525
Antal sider	8
ISSN	0022-3654
Status	Udgivet - 1 dec. 1994

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Citationsformater

Atmospheric chemistry of HFC-143a : Spectrokinetic investigation of the CF₃CH₂O₂^• radical, its reactions with NO and NO₂, and the fate of CF₃CH₂O. / Nielsen, Ole J.; Gamborg, Elisabeth; Sehested, Jens et al.

I: Journal of Physical Chemistry, Bind 98, Nr. 38, 01.12.1994, s. 9518-9525.

Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › peer review

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title = "Atmospheric chemistry of HFC-143a: Spectrokinetic investigation of the CF3CH2O2• radical, its reactions with NO and NO2, and the fate of CF3CH2O",

abstract = "The ultraviolet absorption spectrum of CF3CH2O2 radicals, the kinetics of their self-reaction, and their reactions with NO and NO2 have been studied in the gas phase at 296 K using a pulse radiolysis technique. A long path-length Fourier transform infrared technique was used to study the fate of CF3CH2O radicals. Absorption cross sections were quantified over the wavelength range 220-300 nm. At 250 nm, σ(CF3CH2O2) = (2.73 ± 0.31) × 10-18 molecule-1. By monitoring the rate of NO2 formation, k4 = (1.2 ± 0.3) 10-11 cm3 molecule-1 s-1 was found for the reaction of CF3CH2O2 radical with NO. The reaction of CF3CH2O2 radicals with NO gives CF3CH2O radicals. In the atmosphere, >99.3% of the CF3CH2O radicals react with O2 to give CF3CHO. By monitoring the rate of NO2 decay, k5 = (5.8 ± 1.1) × 10-12 cm3 molecule-1 s-1 was found for the reaction of CF3CH2O2 radical with NO2. The results are discussed with respect to the atmospheric chemistry of CF3CH3 (HFC-143a). As a part of the present work, relative rate techniques were used to measure the following rate constants: (2.6 ± 0.7) × 10-12 and (2.0 ± 0.5) × 10-12 for the reaction of F atoms with CF3CH3, (5.5 ± 0.3) × 10-11 for the reaction of F atoms with CF3CH2OH, and (3.6 ± 0.2) × 10-17 for the reaction with Cl atoms with CF3CH3 (units of cm3 molecule-1 s-1).",

author = "Nielsen, {Ole J.} and Elisabeth Gamborg and Jens Sehested and Wellington, {Timothy J.} and Hurley, {Michael D.}",

year = "1994",

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T1 - Atmospheric chemistry of HFC-143a

T2 - Spectrokinetic investigation of the CF3CH2O2• radical, its reactions with NO and NO2, and the fate of CF3CH2O

AU - Nielsen, Ole J.

AU - Gamborg, Elisabeth

AU - Sehested, Jens

AU - Wellington, Timothy J.

AU - Hurley, Michael D.

PY - 1994/12/1

Y1 - 1994/12/1

N2 - The ultraviolet absorption spectrum of CF3CH2O2 radicals, the kinetics of their self-reaction, and their reactions with NO and NO2 have been studied in the gas phase at 296 K using a pulse radiolysis technique. A long path-length Fourier transform infrared technique was used to study the fate of CF3CH2O radicals. Absorption cross sections were quantified over the wavelength range 220-300 nm. At 250 nm, σ(CF3CH2O2) = (2.73 ± 0.31) × 10-18 molecule-1. By monitoring the rate of NO2 formation, k4 = (1.2 ± 0.3) 10-11 cm3 molecule-1 s-1 was found for the reaction of CF3CH2O2 radical with NO. The reaction of CF3CH2O2 radicals with NO gives CF3CH2O radicals. In the atmosphere, >99.3% of the CF3CH2O radicals react with O2 to give CF3CHO. By monitoring the rate of NO2 decay, k5 = (5.8 ± 1.1) × 10-12 cm3 molecule-1 s-1 was found for the reaction of CF3CH2O2 radical with NO2. The results are discussed with respect to the atmospheric chemistry of CF3CH3 (HFC-143a). As a part of the present work, relative rate techniques were used to measure the following rate constants: (2.6 ± 0.7) × 10-12 and (2.0 ± 0.5) × 10-12 for the reaction of F atoms with CF3CH3, (5.5 ± 0.3) × 10-11 for the reaction of F atoms with CF3CH2OH, and (3.6 ± 0.2) × 10-17 for the reaction with Cl atoms with CF3CH3 (units of cm3 molecule-1 s-1).

AB - The ultraviolet absorption spectrum of CF3CH2O2 radicals, the kinetics of their self-reaction, and their reactions with NO and NO2 have been studied in the gas phase at 296 K using a pulse radiolysis technique. A long path-length Fourier transform infrared technique was used to study the fate of CF3CH2O radicals. Absorption cross sections were quantified over the wavelength range 220-300 nm. At 250 nm, σ(CF3CH2O2) = (2.73 ± 0.31) × 10-18 molecule-1. By monitoring the rate of NO2 formation, k4 = (1.2 ± 0.3) 10-11 cm3 molecule-1 s-1 was found for the reaction of CF3CH2O2 radical with NO. The reaction of CF3CH2O2 radicals with NO gives CF3CH2O radicals. In the atmosphere, >99.3% of the CF3CH2O radicals react with O2 to give CF3CHO. By monitoring the rate of NO2 decay, k5 = (5.8 ± 1.1) × 10-12 cm3 molecule-1 s-1 was found for the reaction of CF3CH2O2 radical with NO2. The results are discussed with respect to the atmospheric chemistry of CF3CH3 (HFC-143a). As a part of the present work, relative rate techniques were used to measure the following rate constants: (2.6 ± 0.7) × 10-12 and (2.0 ± 0.5) × 10-12 for the reaction of F atoms with CF3CH3, (5.5 ± 0.3) × 10-11 for the reaction of F atoms with CF3CH2OH, and (3.6 ± 0.2) × 10-17 for the reaction with Cl atoms with CF3CH3 (units of cm3 molecule-1 s-1).

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M3 - Journal article

AN - SCOPUS:33751157784

SN - 0022-3654

VL - 98

SP - 9518

EP - 9525

JO - Journal of Physical Chemistry

JF - Journal of Physical Chemistry

IS - 38

ER -

Atmospheric chemistry of HFC-143a: Spectrokinetic investigation of the CF3CH2O2• radical, its reactions with NO and NO2, and the fate of CF3CH2O

Abstract

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Fingeraftryk

Citationsformater

Atmospheric chemistry of HFC-143a: Spectrokinetic investigation of the CF₃CH₂O₂^• radical, its reactions with NO and NO₂, and the fate of CF₃CH₂O