Structure and properties of dimer, trimer and tetramer aggregates of methyltrioxorhenium (MTO): An ab initio study

We have performed ab initio Hartree-Fock self-consistent field calculations on the electronic and geometric structure of methyltrioxorhenium (MTO) and its dimers, trimer and tetramer. This latter hypothetic compound has many features in common with the recently discovered polymeric form of MTO, poly-MTO, and the present results show that the tetramer provides a model for the interpretation of the IR and Raman spectra. Based on the tetramer, we also predict some unknown geometrical parameters of poly-MTO. The Re atoms in poly-MTO exhibit an electronic structure which closely resembles that of the Re atom in the monomer. The tetramer results suggest that the negatively charged bridging oxygen atoms in the polymeric form are the best candidates for binding the excess protons present in poly-MTO.