Product study of the reaction of CH 3 with OH radicals at low pressures and temperatures of 300 and 612 K

Christopher Fockenberg, Ralph E. Weston, James Muckerman

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The product distribution for the title reaction was studied using our time-of-flight mass spectrometer (TOFMS) connected to a tubular flow reactor. The methyl and hydroxyl radicals were produced by an excimer laser pulse (λ = 193 nm) photolyzing acetone and nitrous oxide in the presence of excess water or hydrogen. Helium was used as the bath gas; the total density was held constant at 1.2 × 10 17 cm -3. At 300 K the observations were consistent with singlet methylene ( 1CH 2) and water as the main product channel with a small contribution of methanol. In contrast, at about 610 K three channels - formaldehyde isomers and methanol in addition to 1CH 2 + H 2O - are formed with similar yields. When acetone-d 6 was used, the production of both CHDO and CD 2O was observed, indicating that two different formaldehyde-producing channels are operating simultaneously. These experimental results are compared with RRKM and master equation calculations on the basis of the properties of the methanol potential energy surface from a recent ab initio study.

Original languageEnglish
Pages (from-to)8415-8427
Number of pages13
JournalJournal of Physical Chemistry B
Volume109
Issue number17
DOIs
Publication statusPublished - May 5 2005

Fingerprint

Methanol
methyl alcohol
low pressure
methylidyne
Acetone
formaldehyde
Formaldehyde
acetone
products
Helium
Potential energy surfaces
Water
nitrous oxides
Nitrous Oxide
hydroxyl radicals
Excimer lasers
Mass spectrometers
methylene
Isomers
Hydroxyl Radical

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

Product study of the reaction of CH 3 with OH radicals at low pressures and temperatures of 300 and 612 K. / Fockenberg, Christopher; Weston, Ralph E.; Muckerman, James.

In: Journal of Physical Chemistry B, Vol. 109, No. 17, 05.05.2005, p. 8415-8427.

Research output: Contribution to journalArticle

@article{6b542bde639b4a44aaaa361e1ae98d24,
title = "Product study of the reaction of CH 3 with OH radicals at low pressures and temperatures of 300 and 612 K",
abstract = "The product distribution for the title reaction was studied using our time-of-flight mass spectrometer (TOFMS) connected to a tubular flow reactor. The methyl and hydroxyl radicals were produced by an excimer laser pulse (λ = 193 nm) photolyzing acetone and nitrous oxide in the presence of excess water or hydrogen. Helium was used as the bath gas; the total density was held constant at 1.2 × 10 17 cm -3. At 300 K the observations were consistent with singlet methylene ( 1CH 2) and water as the main product channel with a small contribution of methanol. In contrast, at about 610 K three channels - formaldehyde isomers and methanol in addition to 1CH 2 + H 2O - are formed with similar yields. When acetone-d 6 was used, the production of both CHDO and CD 2O was observed, indicating that two different formaldehyde-producing channels are operating simultaneously. These experimental results are compared with RRKM and master equation calculations on the basis of the properties of the methanol potential energy surface from a recent ab initio study.",
author = "Christopher Fockenberg and Weston, {Ralph E.} and James Muckerman",
year = "2005",
month = "5",
day = "5",
doi = "10.1021/jp045792o",
language = "English",
volume = "109",
pages = "8415--8427",
journal = "Journal of Physical Chemistry B Materials",
issn = "1520-6106",
publisher = "American Chemical Society",
number = "17",

}

TY - JOUR

T1 - Product study of the reaction of CH 3 with OH radicals at low pressures and temperatures of 300 and 612 K

AU - Fockenberg, Christopher

AU - Weston, Ralph E.

AU - Muckerman, James

PY - 2005/5/5

Y1 - 2005/5/5

N2 - The product distribution for the title reaction was studied using our time-of-flight mass spectrometer (TOFMS) connected to a tubular flow reactor. The methyl and hydroxyl radicals were produced by an excimer laser pulse (λ = 193 nm) photolyzing acetone and nitrous oxide in the presence of excess water or hydrogen. Helium was used as the bath gas; the total density was held constant at 1.2 × 10 17 cm -3. At 300 K the observations were consistent with singlet methylene ( 1CH 2) and water as the main product channel with a small contribution of methanol. In contrast, at about 610 K three channels - formaldehyde isomers and methanol in addition to 1CH 2 + H 2O - are formed with similar yields. When acetone-d 6 was used, the production of both CHDO and CD 2O was observed, indicating that two different formaldehyde-producing channels are operating simultaneously. These experimental results are compared with RRKM and master equation calculations on the basis of the properties of the methanol potential energy surface from a recent ab initio study.

AB - The product distribution for the title reaction was studied using our time-of-flight mass spectrometer (TOFMS) connected to a tubular flow reactor. The methyl and hydroxyl radicals were produced by an excimer laser pulse (λ = 193 nm) photolyzing acetone and nitrous oxide in the presence of excess water or hydrogen. Helium was used as the bath gas; the total density was held constant at 1.2 × 10 17 cm -3. At 300 K the observations were consistent with singlet methylene ( 1CH 2) and water as the main product channel with a small contribution of methanol. In contrast, at about 610 K three channels - formaldehyde isomers and methanol in addition to 1CH 2 + H 2O - are formed with similar yields. When acetone-d 6 was used, the production of both CHDO and CD 2O was observed, indicating that two different formaldehyde-producing channels are operating simultaneously. These experimental results are compared with RRKM and master equation calculations on the basis of the properties of the methanol potential energy surface from a recent ab initio study.

UR - http://www.scopus.com/inward/record.url?scp=18844422755&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=18844422755&partnerID=8YFLogxK

U2 - 10.1021/jp045792o

DO - 10.1021/jp045792o

M3 - Article

C2 - 16851988

AN - SCOPUS:18844422755

VL - 109

SP - 8415

EP - 8427

JO - Journal of Physical Chemistry B Materials

JF - Journal of Physical Chemistry B Materials

SN - 1520-6106

IS - 17

ER -