Theoretical Study of the Ionized Electronic Structure of the Octahedral Complex MoF₆

The SAC (symmetry adapted cluster) and SAC-CI (SAC-configuration interaction) theories were used to calculate the ground and ionized states of MoF₆. Compared with the results of previous theoretical studies, the present SAC-CI results are in good agreement with experimental data. We clearly show the effects of the electron correlation and ligand-polarization functions. In this molecule, the ligand polarization even affects the HF orbitals. These polarization functions make the electron density of the ligands expand toward the central metal, which leads not only to a stabilization of the total energy, but also to a destabilization of the valence orbital energies. These changes can be explained by changes in the one- and two-electron integrals. On the other hand, the correlation effect makes the electron density of the ligands expand outwards. This is an inverse effect of the polarization functions.