TY - JOUR
T1 - UV absorption spectra and kinetics for alkyl and alkyl peroxy radicals originating from di-tert-butyl ether
AU - Nielsen, O.J.
AU - Sehested, J.
AU - Langer, S.
AU - Ljungström, E.
AU - Wängberg, I.
PY - 1995
Y1 - 1995
N2 - Alkyl, (CH3)(3)COC(CH3)(2)CH2, and alkyl peroxy, (CH3)(3)COC(CH3)(2)CH2O2, radicals from di-tert-butyl ether (DTBE), have been studied in the gas phase at 296 K. A pulse radiolysis UV absorption technique was used to measure the spectra and kinetics. Absorption cross sections were quantified over the wavelength range 220-330 nm. At 240 nm, sigma((CH3)3COC(CH3)2CH2) = (3.6 +/- 0.4) X 10(-18) cm(2) molecule(-1) and at 260 nm, sigma((CH3)3COC(CH3)2CH2) = (3.8 +/- 0.3) X 10(-18) cm(2) molecule(-1) have been obtained. The observed rate constants for the self-reaction of (CH3)(3)COC(CH3)(2)CH2 and (CH3)(3)COC(CH3)(2)CH2O2 radicals were found to be (2.9 +/- 0.2) X 10(-11) cm(3) molecule(-1) s(-1) and (2.7 +/- 0.2) X 10(-12) cm(3) molecule(-1) s(-1), respectively. For the reaction of the alkyl radical with O-2 in 1 atm pressure of SF6 a rate constant of (7.2 +/- 1.1) X 10(-13) cm(3) molecule(-1) s(-1) was found. The rate constants for the reaction of the alkyl peroxy radicals with NO and NO2 were determined to be (1.8 +/- 0.2) X 10(-12) and (9.9 +/- 1.3) X 10(-12) cm(3) molecule(-1) s(-1), respectively. As a part of the work the rate constants k(F + DTBE) and k(OH + DTBE) were determined to be (2.6 +/- 0.6) X 10(-10) and (4.0 +/- 0.9) X 10(-12) cm(3) molecule(-1) s(-1), respectively.
AB - Alkyl, (CH3)(3)COC(CH3)(2)CH2, and alkyl peroxy, (CH3)(3)COC(CH3)(2)CH2O2, radicals from di-tert-butyl ether (DTBE), have been studied in the gas phase at 296 K. A pulse radiolysis UV absorption technique was used to measure the spectra and kinetics. Absorption cross sections were quantified over the wavelength range 220-330 nm. At 240 nm, sigma((CH3)3COC(CH3)2CH2) = (3.6 +/- 0.4) X 10(-18) cm(2) molecule(-1) and at 260 nm, sigma((CH3)3COC(CH3)2CH2) = (3.8 +/- 0.3) X 10(-18) cm(2) molecule(-1) have been obtained. The observed rate constants for the self-reaction of (CH3)(3)COC(CH3)(2)CH2 and (CH3)(3)COC(CH3)(2)CH2O2 radicals were found to be (2.9 +/- 0.2) X 10(-11) cm(3) molecule(-1) s(-1) and (2.7 +/- 0.2) X 10(-12) cm(3) molecule(-1) s(-1), respectively. For the reaction of the alkyl radical with O-2 in 1 atm pressure of SF6 a rate constant of (7.2 +/- 1.1) X 10(-13) cm(3) molecule(-1) s(-1) was found. The rate constants for the reaction of the alkyl peroxy radicals with NO and NO2 were determined to be (1.8 +/- 0.2) X 10(-12) and (9.9 +/- 1.3) X 10(-12) cm(3) molecule(-1) s(-1), respectively. As a part of the work the rate constants k(F + DTBE) and k(OH + DTBE) were determined to be (2.6 +/- 0.6) X 10(-10) and (4.0 +/- 0.9) X 10(-12) cm(3) molecule(-1) s(-1), respectively.
KW - Atmosfæriske processers betydning for miljøet
U2 - 10.1016/0009-2614(95)00401-O
DO - 10.1016/0009-2614(95)00401-O
M3 - Journal article
SN - 0009-2614
VL - 238
SP - 359
EP - 364
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 4-6
ER -