A modified parametrization scheme for the complete neglect of differential overlap method with relativistic correction of orbital exponents and energy levels with particular applications to rare earth compounds

Wu, G. S.; Ma, H.; Lin, S. H.
March 1992
Journal of Chemical Physics;3/15/1992, Vol. 96 Issue 6, p4518
Academic Journal
A new unified parametrization scheme for the complete neglect of differential overlap method, applicable to heavy atom systems is formulated. The exponents ζμ and electronegativities X(μ) of atomic orbitals are corrected by the relativistic Dirac–Fock expectation values of atomic orbital radii and energy levels. This leads to the possibility of calibrating the β0 parameters directly by the equilibrium geometric configuration of molecules. The parametrization for hydrogen, halides, and rare earth series, as well as some test calculations for compounds of these elements, have been carried out to show the utility of the scheme. The results demonstrate that the present scheme can give satisfactory MO levels and ionization potentials as well as correct molecular geometry.


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