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Title: Ab initio studies of hydrocarbon peroxyl radicals

Abstract

Extensive ab initio molecular orbital calculations have been performed for the importance series of peroxyl radicals (O/sub 2//sup .-/), HO/sub 2//sup ./, CH/sub 3/O/sub 2//sup ./, (CH/sub 3/)/sub 2/CHO/sub 2//sup ./, and (CH/sub 3/CH/sub 2/)/sub 2/CHO/sub 2//sup ./. Parameters calculated include equilibrium geometries, harmonic vibrational frequencies, dipole moments, and isotropic and anisotropic hyperfine couplings. Equilibrium geometries were of primary interest. In the two large hydrocarbon peroxyl radicals the carbon atoms and appropriate hydrogen atoms were constrained to be coplanar and the O-O group was forced to be perpendicular to the carbon chain in order to stimulate the presence of a peroxyl radical site in a polyethylene chain. Calculations were performed with large Gaussian basis sets (up to 6-311 ++G(d,p)). Calculations for HO/sub 2//sup ./ including electron correlation utilizing Moeller-Plesset perturbation theory were performed at the following levels: MP2(6-31G(d)) and 6-311G(d,p), MP3(6-311G(d,p)) and MP4SDTQ(6-311(d,p)). Calculated values are compared against the highly accurate experimental data for HO/sub 2//sup ./ known from microwave, laser magnetic resonance, and diode laser studies in order to determine the level of calculation necessary for accurate predictions. Comparison of the various calculations shows that MP2(6-31G(d)) compares favorably with MP4SDTQ(6-311G(d,p)) at a considerable savings in computation time.

Authors:
; ;
Publication Date:
Research Org.:
Oakland Univ., Rochester, MI
OSTI Identifier:
6953033
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Phys. Chem.; (United States); Journal Volume: 90:24
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 54 ENVIRONMENTAL SCIENCES; ORGANIC COMPOUNDS; HYPERFINE STRUCTURE; MOLECULAR STRUCTURE; PEROXY RADICALS; COUPLING; DIPOLE MOMENTS; MOLECULAR ORBITAL METHOD; PERTURBATION THEORY; THEORETICAL DATA; VIBRATIONAL STATES; DATA; ENERGY LEVELS; EXCITED STATES; INFORMATION; NUMERICAL DATA; RADICALS; 400201* - Chemical & Physicochemical Properties; 500200 - Environment, Atmospheric- Chemicals Monitoring & Transport- (-1989)

Citation Formats

Besler, B.H., Sevilla, M.D., and MacNeille, P. Ab initio studies of hydrocarbon peroxyl radicals. United States: N. p., 1986. Web. doi:10.1021/j100282a009.
Besler, B.H., Sevilla, M.D., & MacNeille, P. Ab initio studies of hydrocarbon peroxyl radicals. United States. doi:10.1021/j100282a009.
Besler, B.H., Sevilla, M.D., and MacNeille, P. Thu . "Ab initio studies of hydrocarbon peroxyl radicals". United States. doi:10.1021/j100282a009.
@article{osti_6953033,
title = {Ab initio studies of hydrocarbon peroxyl radicals},
author = {Besler, B.H. and Sevilla, M.D. and MacNeille, P.},
abstractNote = {Extensive ab initio molecular orbital calculations have been performed for the importance series of peroxyl radicals (O/sub 2//sup .-/), HO/sub 2//sup ./, CH/sub 3/O/sub 2//sup ./, (CH/sub 3/)/sub 2/CHO/sub 2//sup ./, and (CH/sub 3/CH/sub 2/)/sub 2/CHO/sub 2//sup ./. Parameters calculated include equilibrium geometries, harmonic vibrational frequencies, dipole moments, and isotropic and anisotropic hyperfine couplings. Equilibrium geometries were of primary interest. In the two large hydrocarbon peroxyl radicals the carbon atoms and appropriate hydrogen atoms were constrained to be coplanar and the O-O group was forced to be perpendicular to the carbon chain in order to stimulate the presence of a peroxyl radical site in a polyethylene chain. Calculations were performed with large Gaussian basis sets (up to 6-311 ++G(d,p)). Calculations for HO/sub 2//sup ./ including electron correlation utilizing Moeller-Plesset perturbation theory were performed at the following levels: MP2(6-31G(d)) and 6-311G(d,p), MP3(6-311G(d,p)) and MP4SDTQ(6-311(d,p)). Calculated values are compared against the highly accurate experimental data for HO/sub 2//sup ./ known from microwave, laser magnetic resonance, and diode laser studies in order to determine the level of calculation necessary for accurate predictions. Comparison of the various calculations shows that MP2(6-31G(d)) compares favorably with MP4SDTQ(6-311G(d,p)) at a considerable savings in computation time.},
doi = {10.1021/j100282a009},
journal = {J. Phys. Chem.; (United States)},
number = ,
volume = 90:24,
place = {United States},
year = {Thu Nov 20 00:00:00 EST 1986},
month = {Thu Nov 20 00:00:00 EST 1986}
}
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