Photochemistry of matrix-isolated and thin film acid chlorides: Quantum yields and product structures

Journal Article · Thu Feb 18 04:00:00 EST 1999 · Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory

DOI:https://doi.org/10.1021/jp9837481· OSTI ID:335229

Rowland, B; Hess, W P ^[1]; Winter, P R; Ellison, G B ^[2]; Radziszewski, J G ^[3]

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1. Pacific Northwest National Lab., Richland, WA (United States)
2. Univ. of Colorado, Boulder, CO (United States). Dept. of Chemistry and Biochemistry
3. National Renewable Energy Lab., Golden, CO (United States)

Ultraviolet photoexcitation of matrix-isolated CH{sub 3}COCl, CH{sub 3}CH{sub 2}COCl, and CH{sub 3}CH{sub 2}CH{sub 2}CH{sub 2}COCl produces HCl{center_dot}CH{sub 2}{double_bond}C{double_bond}O, HCl{center_dot}CH{sub 3}CHC{double_bond}C{double_bond}O, and HCl{center_dot}CH{sub 3}CH{sub 2}CH{sub 2}CHC{double_bond}C{double_bond}O complexes. The authors report precursor and matrix dependent reaction quantum yields. Quantum yield values decrease with increasing alkyl chain length due to a reduced number of {alpha} H-atoms available for the elimination reaction and steric considerations. The authors found quantum yields in neat matrixes to be roughly half that in argon or xenon matrixes and assign structures for HCL and ketene complexes in argon and xenon matrixes by comparing IR spectra ab initio electronic structure calculations. In argon matrixes, the product complex HCl frequently is strongly shifted whereas the ketene remains unshifted with respect to matrix-isolated ketene. In xenon matrixes, HCl{center_dot}ketene complexes display absorption bands indicative of two distinct structures. Differences between HCl{center_dot}ketene structures in argon and xenon matrixes are attributed to size differences of the matrix lattice.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 335229
• Journal Information: Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory, Journal Name: Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory Journal Issue: 7 Vol. 103; ISSN 1089-5639; ISSN JPCAFH
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
CHEMICAL REACTION YIELD
ORGANIC ACIDS
ORGANIC CHLORINE COMPOUNDS
PHOTOCHEMISTRY
QUANTUM ELECTRONICS
ULTRAVIOLET RADIATION