The electronic structure of octahedral transition metal halides as calculated by the multiple scattering method

The multiple scattering formalism with Xα exchange and muffin-tin potentials is used in a study of the electronic structure of several octahedral transition metal complexes. The calculated orbital energies are ordered in agreement with the traditional opinion with antibonding orbitals of ee and t2g symmetry as highest occupied molecular orbitals. The splittings in orbital energies agree well with measured 10Dq values. Calculated spin densities are in fair agreement with experiments. The role of spin polarization is found to be greater than believed previously. The 3s splitting in the x-ray photoelectron spectra has been examined. For d5 systems a larger reduction of the splitting for more covalent bonding was obtained in agreement with experiments, whereas for d3 systems the opposite result was found, contrary to experimental evidence. Mössbauer isomer shifts have been studied. The pressure shift is found to be crucially dependent on the choice of muffin-tin sphere radii. The shifts between Fe3+, Fe2+, and Fe+ agree with other calculations and with experiments, provided a calibration constant α = 0.35a30, mm/sec is used.