Formation of methoxy and hydroxymethyl free radicals in selected elementary reactions

Dóbé, Sándor; Bérces, T.; Temps, F.; Wagner, H. Gg.; Ziemer, H.

doi:10.1016/s0082-0784(06)80710-1

Cited by 31 publications

(23 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[17][18][19] Besides, both reaction channels are highly exothermic, with À28.40 and À37.74 kcal mol À1 for (R1) and (R2), respectively. 18,19 The measured branching ratios, dened as the ratio of the thermal rate constants k R1 /(k R1 + k R2 ), vary between 0.4 and 0.6, [20][21][22][23][24][25][26][27] and are all greater than the 0.25 value expected from the statistical limit (one H out of four possible ones).…”

Section: Introductionmentioning

confidence: 90%

“…[29][30][31] Therefore, a large number of investigations, in particular experimental ones, have been carried out on the kinetics, branching ratios of the two channels, and dynamics for reactions of F atoms with CH 3 OH and the various deuterated isotopologues, CD 3 OH, CH 3 OD, and CD 3 OD. [17][18][19][20][21][22][23][24][25][26][27]29,[32][33][34][35][36][37][38][39][40][41][42] Considerable attention has also been directed toward measuring product-state or energy distributions. Internal state distributions of the nascent HF product have been measured by infra-red chemiluminescence and laser induced uorescence and found to be inverted in both product channels.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Stereodynamical control of product branching in multi-channel barrierless hydrogen abstraction of CH₃OH by F

Lü

Guo

2019

Chem. Sci.

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 90%

Section: Introductionmentioning

confidence: 99%

Stereodynamical control of product branching in multi-channel barrierless hydrogen abstraction of CH₃OH by F

Lü

Guo

2019

Chem. Sci.

View full text Add to dashboard Cite

show abstract

“…The preferred 298 K value is the unweighted average of the absolute rate coefficients of , , Dóbé et al (1993) and , and the relative rate studies of and . The inclusion of the data of on Cl+CH 3 OD is justified considering the strong body of evidence showing that the H-abstraction proceeds solely at the CH 2 -group at room temperature (see , Radford et al, 1981and Jodkowski et al, 1998.…”

Section: Comments On Preferred Valuesmentioning

confidence: 99%

Evaluated kinetic and photochemical data for atmospheric chemistry: Volume II – gas phase reactions of organic species

et al. 2006

View full text Add to dashboard Cite

Abstract. This article, the second in the series, presents kinetic and photochemical data evaluated by the IUPAC Subcommittee on Gas Kinetic Data Evaluation for Atmospheric Chemistry. It covers the gas phase and photochemical reactions of Organic species, which were last published in 1999, and were updated on the IUPAC website in late 2002, and subsequently during the preparation of this article. The article consists of a summary table of the recommended rate coefficients, containing the recommended kinetic parameters for the evaluated reactions, and eight appendices containing the data sheets, which provide information upon which the recommendations are made.

show abstract

“…It is known that Cl atoms exclusively attack one of the three methyl protons in methanol (Dóbé et al 1994). Formaldehyde was easily detected, and the optimized partial pressure of methanol is slightly below the maximum of formaldehyde detected (observing the J K a ,K c = 3 1,2 ← 2 1,1 line near 225 697.8 MHz).…”

Section: Identification Of the Spectrummentioning

confidence: 98%

Laboratory detection of the rotational-tunnelling spectrum of the hydroxymethyl radical, CH₂OH

Bermúdez

Bailleux

Cernicharo

2017

A&A

View full text Add to dashboard Cite

Context. Of the two structural isomers of CH 3 O, methoxy is the only radical whose astronomical detection has been reported through the observation of several rotational lines at 2 and 3 mm wavelengths. Although the hydroxymethyl radical, CH 2 OH, is known to be thermodynamically the most stable (by~3300 cm −1 ), it has so far eluded rotational spectroscopy presumably because of its high chemical reactivity. Aims. Recent high-resolution (~10 MHz) sub-Doppler rovibrationally resolved infrared spectra of CH 2 OH (symmetric CH stretching a-type band) provided accurate ground vibrational state rotational constants, thus reviving the quest for its millimeter-wave spectrum in laboratory and subsequently in space. Methods. The search and assignment of the rotational spectrum of this fundamental species were guided by our quantum chemical calculations and by using rotational constants derived from high-resolution IR data. The hydroxymethyl radical was produced by hydrogen abstraction from methanol by atomic chlorine. Results. Ninety-six b-type rotational transitions between the v = 0 and v = 1 tunnelling sublevels involving 25 fine-structure components of Q branches (with K a = 1 ← 0) and 4 fine-structure components of R branches (assigned to K a = 0 ← 1) were measured below 402 GHz. Hyperfine structure alternations due to the two identical methylenic hydrogens were observed and analysed based on the symmetry and parity of the rotational levels. A global fit including infrared and millimeter-wave lines has been conducted using Pickett's reduced axis system Hamiltonian. The recorded transitions (odd ∆K a ) did not allow us to evaluate the Coriolis tunnelling interaction term. The comparison of the experimentally determined constants for both tunnelling levels with their computed values secures the long-awaited first detection of the rotational-tunnelling spectrum of this radical. In particular, a tunnelling rate of 139.73 ± 0.10 MHz (4.6609(32) × 10 −3 cm −1 ) was obtained along with the rotational constants, electron spin-rotation interaction parameters and several hyperfine coupling terms. Conclusions. The laboratory characterization of CH 2 OH by millimeter-wave spectroscopy now offers the possibility for its astronomical detection for the first time.

show abstract

Formation of methoxy and hydroxymethyl free radicals in selected elementary reactions

Cited by 31 publications

References 26 publications

Stereodynamical control of product branching in multi-channel barrierless hydrogen abstraction of CH₃OH by F

Stereodynamical control of product branching in multi-channel barrierless hydrogen abstraction of CH₃OH by F

Evaluated kinetic and photochemical data for atmospheric chemistry: Volume II – gas phase reactions of organic species

Laboratory detection of the rotational-tunnelling spectrum of the hydroxymethyl radical, CH₂OH

Contact Info

Product

Resources

About

Formation of methoxy and hydroxymethyl free radicals in selected elementary reactions

Cited by 31 publications

References 26 publications

Stereodynamical control of product branching in multi-channel barrierless hydrogen abstraction of CH3OH by F

Stereodynamical control of product branching in multi-channel barrierless hydrogen abstraction of CH3OH by F

Evaluated kinetic and photochemical data for atmospheric chemistry: Volume II – gas phase reactions of organic species

Laboratory detection of the rotational-tunnelling spectrum of the hydroxymethyl radical, CH2OH

Contact Info

Product

Resources

About

Stereodynamical control of product branching in multi-channel barrierless hydrogen abstraction of CH₃OH by F

Stereodynamical control of product branching in multi-channel barrierless hydrogen abstraction of CH₃OH by F

Laboratory detection of the rotational-tunnelling spectrum of the hydroxymethyl radical, CH₂OH