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 b een investigated by the density functional approach. Comparison with c onventional post-Hartree-Fock methods shows that DF results are compet itive with MP2 results for geometries and harmonic frequencies and wit h coupled cluster computations of hyperfine couplings. The results are in good agreement with experimental data and offer a comprehensive pi cture of substituent effects on geometric and electronic characteristi cs. The accuracy of the results and the feasibility of this kind of co mputation for large systems indicate that DF methods can be particular ly useful to those researchers seeking cogent relationships between st ructure and spectroscopy.