Electronic Structure and Hydration of Tetramine Cobalt Hydride Complexes

In this work we have studied two hydridotetraminecobalt(III) complexes using a mixture of computational techniques. These species were chosen as simple and computationally tractable models of the Co(III)–hydrido compounds that are known to be important intermediates in the catalytic cycles of hydrogen evolution mediated by the cobaloxime complexes. We have performed both static density functional theory (DFT) calculations of the complexes in implicit solvent and adaptive hybrid DFT/molecular mechanical (MM) molecular dynamics (MD) simulations in explicit solvent and compared our results to the experimental structural and spectral data that are available for one of the compounds. A principal aim of the study has been to provide a benchmark for future work on cobaloxime and other hydrogen-evolving catalysts using adaptive DFT/MM MD methods.