CO Formation in the 254 nm Gas Phase Photolysis of Nitrosobenzene-Oxygen Mixtures at Room Temperature
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Abstract
Large CO yields were detected in the gas phase photolysis of nitrosobenzene at 254 nm in the presence of O2 and N2 by long-path IR absorption in a 200 L photoreactor made of quartz. CO yields were measured at 298 K for partial pressures of O2 between 1 μbar and 1 bar and total pressures from 10 μbar to 1 bar. Depending on reaction conditions, the CO yield varied between ≤ 1 % (at pN2 = 1 bar, pO2 ≤ 120 μbar) and ≈ 100 % (for pO2 = 20 μbar, pN2 = 0). The dependencies of the CO yield (i) from the O2 partial pressure in O2-N2-mixtures at a total pressure of 1 bar, (ii) from the O2 pressure in the absence of N2, and (iii) from the total pressure at constant O2 pressures show very different behaviour. They can be reproduced well by a mechanism involving vibrationally excited phenyl (C6H5*), phenylperoxy (C6H5O2*) and phenoxyl (C6H5O*) radicals where collisional relaxation of the excited radicals competes with O2 addition for C6H5* and with both unimolecular decomposition and reaction with O2 for C6H5O2* and/or C6H5O*. The measured CO yields allow to select reaction conditions where nearly exclusively either highly vibrationally excited C6H5, C6H5O2 and/or C6H5O radicals (for CO yields ≈ 1) or thermally distributed C6H5, C6H5O2 and/or C6H5O radicals (for CO yields ≤ 1 %) are formed.
© by Oldenbourg Wissenschaftsverlag, München, Germany
Articles in the same Issue
- Preface
- Towards Simplified Thermal and Specific Rigidity Factors for Ion-Molecule Reactions and Ion Fragmentations
- Chemistry and Microphysics of Atmospheric Aerosol Surfaces: Laboratory Techniques and Applications
- The Products of the Reactions of o-Benzyne with Ethene, Propene, and Acetylene: A Combined Mass Spectrometric and Quantum Chemical Study
- CH2Cl and CHCl2 Radical Chemistry: The Formation by the Reactions CH3Cl + F and CH2Cl2 + F and The Destruction by the Reactions CH2Cl + O and CHCl2 + O
- Formation of H-atoms in the Pyrolysis of 1,3-butadiene and 2-butyne: A Shock Tube and Modelling Study
- High-level Ab-initio Calculations for Astrochemically Relevant Polyynes (HC2nH), their Isomers (C2nH2) and their Anions (C2nH−)
- Investigation of the Hierarchical Structure of Kinetic Models in Ignition Problems
- Laser Diagnostics for the Model Development in Turbulent Premixed Flames
- Sampling Probe Influences on Temperature and Species Concentrations in Molecular Beam Mass Spectroscopic Investigations of Flat Premixed Low-pressure Flames
- Shock-Tube Study of the Reactions of Hydrogen Atoms with Benzene and Phenyl Radicals
- The Generation of a Compact n-Heptane / Toluene Reaction Mechanism Using the Chemistry Guided Reduction (CGR) Technique
- Modeling of Rich Premixed C2H4/O2/Ar and C2H4/Dimethoxymethane/O2/Ar Flames
- Conformation and Aggregation of Proline Esters and Their Aromatic Homologs: Pyramidal vs. Planar RR´N-H in Hydrogen Bonds
- A Two-equation Model to Simulate Soot Formation under Shock-tube Conditions
- CO Formation in the 254 nm Gas Phase Photolysis of Nitrosobenzene-Oxygen Mixtures at Room Temperature
- Experimental and Numerical Investigation of Fe(CO)5 Addition to a Laminar Premixed Hydrogen/Oxygen/Argon Flame
- Structures of Laminar Methane/Nitrogen/Oxygen, Methane/Oxygen and Methane/Liquid Oxygen Counterflow Flames for Cryogenic Conditions and Elevated Pressures
Articles in the same Issue
- Preface
- Towards Simplified Thermal and Specific Rigidity Factors for Ion-Molecule Reactions and Ion Fragmentations
- Chemistry and Microphysics of Atmospheric Aerosol Surfaces: Laboratory Techniques and Applications
- The Products of the Reactions of o-Benzyne with Ethene, Propene, and Acetylene: A Combined Mass Spectrometric and Quantum Chemical Study
- CH2Cl and CHCl2 Radical Chemistry: The Formation by the Reactions CH3Cl + F and CH2Cl2 + F and The Destruction by the Reactions CH2Cl + O and CHCl2 + O
- Formation of H-atoms in the Pyrolysis of 1,3-butadiene and 2-butyne: A Shock Tube and Modelling Study
- High-level Ab-initio Calculations for Astrochemically Relevant Polyynes (HC2nH), their Isomers (C2nH2) and their Anions (C2nH−)
- Investigation of the Hierarchical Structure of Kinetic Models in Ignition Problems
- Laser Diagnostics for the Model Development in Turbulent Premixed Flames
- Sampling Probe Influences on Temperature and Species Concentrations in Molecular Beam Mass Spectroscopic Investigations of Flat Premixed Low-pressure Flames
- Shock-Tube Study of the Reactions of Hydrogen Atoms with Benzene and Phenyl Radicals
- The Generation of a Compact n-Heptane / Toluene Reaction Mechanism Using the Chemistry Guided Reduction (CGR) Technique
- Modeling of Rich Premixed C2H4/O2/Ar and C2H4/Dimethoxymethane/O2/Ar Flames
- Conformation and Aggregation of Proline Esters and Their Aromatic Homologs: Pyramidal vs. Planar RR´N-H in Hydrogen Bonds
- A Two-equation Model to Simulate Soot Formation under Shock-tube Conditions
- CO Formation in the 254 nm Gas Phase Photolysis of Nitrosobenzene-Oxygen Mixtures at Room Temperature
- Experimental and Numerical Investigation of Fe(CO)5 Addition to a Laminar Premixed Hydrogen/Oxygen/Argon Flame
- Structures of Laminar Methane/Nitrogen/Oxygen, Methane/Oxygen and Methane/Liquid Oxygen Counterflow Flames for Cryogenic Conditions and Elevated Pressures
