SEMIEMPIRICAL CALCULATION TECHNIQUE FOR TRANSITION-METAL COMPOUNDS INLOW OXIDATION-STATES

The feasibility of employing the semiempirical MC SCF method to model chemical processes is analyzed with the aid of transition metal compou nds in the lowest oxidation states. Using the nickel compounds Ni-2, N iCO, Ni-4, NiO, and Ni(CO)(4) as examples, it is shown that with the m ulticonfiguration INDO method it is possible to give an accurate descr iption of the molecular wavefunction form over a broad range of intera tomic distances and to convey the relative order of the lowest molecul ar terms and the shape of potential curves. Parametrization of the tra nsition metals M is proposed on the basis of spectroscopic data on the lowest term energies of the M(O) atoms and the M(+) ions.