Comparison of convetional and hybrid density functional approaches. Cationic hydrides of first-row transition metals as a case study

A parallel study by different conventional and hybrid density functional methods has been performed for the whole series of binary cationic hydrides of first row transition metals. The results show that hybrid methods represent a significant improvement over standard density functionals, reaching an accuracy comparable to that of the most sophisticated post-Hartree-Fock approaches. among the different hybrid methods, the B3LYP variant seems to provide the most balanced results. In all cases converged results are obtained with basis sets small enough to be applied in the study of large systems.