Evaluation of functionals O3LYP, KMLYP, and MPW1K in comparison to B3LYP for selected transition-metal compounds

We have investigated the performance of the hybrid density functionals O3LYP, KMLYP, and MPW1K in comparison to B3LYP for predicting geometrical parameters of selected transition-metal compounds. We used different combinations of ECPs and basis sets (Stuttgart/ Dresden 1997, LANL2DZ, 6-31 G(d), 6-311 ++G(d,p)) to analyze the effect on selected transition-metal compounds. B3LYP is superior to the other three density functionals for the split valence double-xi basis set 6-31G(d), contrary to what was reported for organic reactions. But in combination with the split valence triple-xi basis set 6-311 ++G(d,p) O3LYP was clearly superior to all the other functionals. LANL2DZ performed worse in every case.