Theoretical study of hyperfine coupling constants in ethyl radical
- 15 May 1991
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 94 (10) , 6632-6637
- https://doi.org/10.1063/1.460290
Abstract
Spin densities that determine hyperfine splitting constants are calculated for ethyl radical from ab initio electronic wave functions. The most important direct and spin polarization contributions are obtained from single‐excitation configuration interaction wave functions, in conjunction with recently developed contracted Gaussian basis sets designed specifically for spin density determination. Facile out‐of‐plane bending at the α‐carbon center leads to a significant vibrational correction and temperature dependence for the α‐carbon splitting. Coupling of torsion about the CC bond with bending at the α‐carbon is found to have only a small effect on the hyperfine constants. For isotropic Fermi contact interactions, agreement with experiment is better than 10% for both carbons and for the α‐hydrogens. The larger 28% error found for the β‐hydrogens is attributed primarily to the missing effects of electron correlation. Anisotropic dipolar hyperfine constants are also evaluated and agree well with experiment wherever comparison is possible.Keywords
This publication has 30 references indexed in Scilit:
- On the interpretation of muon spin rotation and level-crossing resonance observations on the muonic ethyl radicalChemical Physics Letters, 1988
- Angular dependence of the β-proton hyperfine coupling constant in β-substituted ethyl radicalsChemical Physics Letters, 1987
- Structures and conformational analysis of the fluorinated ethyl radicals of CF3CH2., CH3CF2., and CF3CF2.: an ab initio SCF MO studyJournal of Molecular Structure: THEOCHEM, 1987
- Comment on ab initio calculation of spin densities in hydrocarbon radicalsThe Journal of Chemical Physics, 1983
- A b i n i t i o calculation of hyperfine splitting constants of moleculesThe Journal of Chemical Physics, 1980
- A b i n i t i o calculation of spin densities in hydrocarbon radicalsThe Journal of Chemical Physics, 1979
- AB initio MO LCAO UHF calculations of magnetic hyperfine interactions in π-radicals. Isotropic and anisotropic couplings of ·CH3, ·NH3+, ·C2H5 and ·N2H4+Chemical Physics, 1975
- Ab initio unrestricted Hartree–Fock calculations. Part 9.–Hyperfine coupling constants in the ethyl radicalJournal of the Chemical Society, Faraday Transactions 2: Molecular and Chemical Physics, 1974
- Ab initio calculations on large molecules using molecular fragments. Initial studies on open shell systemsChemical Physics Letters, 1973
- Interplay of direct and indirect coupling contributions in proton hyperfine splitting constants of alkyl radicalsChemical Physics Letters, 1971