Very low pressure reactor chemiluminescence studies on N atom reactions with CHCl sub 3 and CDCl sub 3

Journal Article · Thu Sep 19 00:00:00 EDT 1991 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100172a035· OSTI ID:5260470

Benson, S W ^[1]

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1. Univ. of Southern California, Los Angeles (United States)

Ground-state (N(S{sup 4})) nitrogen atom reactions with chloroform-h and chloroform-d were studied by using the VLPR technique at room temperature. Relative N atom concentrations were monitored via mass spectrometry, and their absolute values were determined by the chemical titration reaction with nitric oxide. It was possible to obtain a more accurate constant for the bimolecular reaction: N + NO {yields} N{sub 2} + O, k{sub NO} = (2.4 {plus minus} 0.2) {times} 10{sup {minus}11} cm{sup 3} molecule{sup {minus}1} s{sup {minus}1} at 298 {Kappa}. N atom decay in the presence of CHCl{sub 3} and CDCl{sub 3} was found to have an apparent induction period and to have a large isotope effect. Chemiluminescence signals emitted from the reactor in the range of 300-600 nm were also observed, and identified as coming from the excited CN radical. The detailed study of reaction products, intermediates, N atom decay kinetics, and chemiluminescence signals are interpreted by a slow reaction of C1 atoms with CHCl{sub 3} followed by fast branching chain reactions of N atoms with the intermediate radicals. A successful numerical simulation of the experimental results supports the suggested chain branching mechanism. The following rate constants were estimated from the experimental results: k{sub 1}(N + CHCl{sub 3} {yields} NCl + CHCl{sub 2}), 1.00 {times} 10{sup {minus}16}, k{sub 2}(N + NCl {yields} N + Cl), 2.57 {times} 10{sup {minus}11}, K{sub 3}(Cl + CHCl{sub 3} {yields} HCl + CCl{sub 3}), 3.70 {times} 10{sup {minus}14}, k{sub 3D}(Cl + CDCl{sub 3} {yields} DCl + CCl{sub 3}), 0.95 {times} 10{sup {minus}14}, and k{sub 7}(N + CCl {yields} CN(B{sup 2}{Sigma}{sup +}{sub u}) + Cl), 5.70 {times} 10{sup {minus}13}, all in the units of cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}.

• OSTI ID: 5260470
• Journal Information: Journal of Physical Chemistry; (United States), Vol. 95:19; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CHLOROFORM
CHEMILUMINESCENCE
NITRIFICATION
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DEUTERIUM
EXPERIMENTAL DATA
GROUND STATES
HIGH VACUUM
ISOTOPE EFFECTS
LABELLED COMPOUNDS
MASS SPECTROSCOPY
MATHEMATICAL MODELS
NITRIC OXIDE
NITROGEN
QUANTITATIVE CHEMICAL ANALYSIS
QUANTITY RATIO
RADICALS
THEORETICAL DATA
TITRATION
ULTRAVIOLET RADIATION
VISIBLE RADIATION
CHALCOGENIDES
CHEMICAL ANALYSIS
CHLORINATED ALIPHATIC HYDROCARBONS
DATA
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY LEVELS
HALOGENATED ALIPHATIC HYDROCARBONS
HYDROGEN ISOTOPES
INFORMATION
ISOTOPES
KINETICS
LIGHT NUCLEI
LUMINESCENCE
NITROGEN COMPOUNDS
NITROGEN OXIDES
NONMETALS
NUCLEI
NUMERICAL DATA
ODD-ODD NUCLEI
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
RADIATIONS
REACTION KINETICS
SPECTROSCOPY
STABLE ISOTOPES
400201* - Chemical & Physicochemical Properties