On the prediction of 51V hyperfine coupling constants in V(IV)O complexes through DFT methods.

Density functional theory (DFT) calculations of the (51)V hyperfine coupling constants for 22 representative V(IV)O complexes with different donor set, electric charge and geometry were performed with Gaussian 03 software. The prediction of A tensor was carried out with five functionals (B3LYP, B3P86, B3PW91, BHandHLYP and BHandH) and four basis sets (6-31g, 6-311g, 6-311+g and 6-311g(d,p)). An excellent agreement with the experimental A(z) value (A(z)(exptl)) was obtained using half-and-half hybrid functionals, such as BHandHLYP or BHandH. They, coupled with the 6-311g(d,p) basis set, yield deviations from |A(z)|(exptl) lower than 5% and, in most of the cases, lower than 3%.