A CHARGE-ITERATIVE HAMILTONIAN FOR MOLECULAR ELECTRONIC-SPECTRA

A complete charge-dependent INDO model Hamiltonian appropriate for the calculation of molecular spectra is developed and examined. A procedure for the acquisition of atomic and molecular parameters is presented that makes use of readily available experimental data. Simplified parameter functions, allowing more information to be incorporated into the model with less effort than is the case for previous parametrization strategies, are suggested. The charge-iterative model forwarded here surpasses the current spectroscopic INDO Hamiltonian in the quantitative prediction of n-pi-* excitation energies for carbonyls without loss of accuracy in the prediction of pi-pi-* excitation energies.