DENSITY-FUNCTIONAL APPROACH TO THE STRUCTURES AND EPR PARAMETERS OF OPEN-SHELL SYSTEMS - THE CASE OF FLUOROVINYL RADICALS

The structures and EPR parameters of fluorinated vinyl radicals have been investigated by the density functional approach. Comparison with conventional post-Hartree-Fock methods shows that DF results are competitive with MP2 results for geometries and harmonic frequencies and with coupled cluster computations of hyperfine couplings. The results are in good agreement with experimental data and offer a comprehensive picture of substituent effects on geometric and electronic characteristics. The accuracy of the results and the feasibility of this kind of computation for large systems indicate that DF methods can be particularly useful to those researchers seeking cogent relationships between structure and spectroscopy.