MODEL POTENTIAL IN SPECTRAL REPRESENTATION FORM - ITS FIDELITY TO THEFROZEN-CORE OPERATOR AND COMPARISON WITH OTHER MODEL POTENTIALS

The model potential, in which the Coulomb and exchange core operators are converted to the matrix elements by use of the spectral representa tion technique, should be equivalent to the frozen-core operator, if t he basis set of the spectral representation is complete. Its fidelity to the frozen-core operator is examined in this paper through a thorou gh study of basis set convergence in both the spectral space and the a tomic orbital space, along with comparison with the Sakai-Huzinaga and the Huzinaga-Seijo-Barandiaran-Klobukowski model potentials. The RHF molecular calculations on N-2, P-2, As-2, Sb-2, PN, and AsN show that the present model potential can approximate, with reliable accuracy, t he results obtained from the frozen-core calculations.