Electronic Structure of Molecules, Clusters and Surfaces Using Ab Initio Relativistic Effective Core and Core/Valence Polarization Potentials

摘要: One of the most difficult problems that must be addressed in ab initio calculations many-electron, multi-center wavefunctions is prediction accuracy. All procedures based on linear combinations atomic orbitals to form molecular (LCAO-MO) context Hartree-Fock (HF) and subsequent post-HF such as configuration interaction (CI), many-body perturbation theory (MBPT) its varients, face an assement.1 This particularly true for commonly used methods, which involve choosing a basis set finite size define LCAO-MOs. The use Slater-type (STO) or primitive Cartesian Gaussian-type (GTO), often incorporating some level contraction (CGTOs) self-consistent field (SCF) has been extensively studied.1,2 importance sets are both carefully optimized contain sufficient number functions cannot overstated. Furthermore, once this established, address additional concern quality one-electron SCF multi-configuration (MCSCF) MO electron configurations (in CI) excitations MBPT) many-electron wavefunction desired electronic state.