Hartree-Fock crystal field theory

Historically, crystal field theory was the first theoretical model (11, 86, 101, 123) used to explain d-d transition energies in metal complexes. Its usefulness is restricted to those complexes whose bonding is largely ionic, and its mqjor deficiency arises from its inability to account for charge transfer transitions. The iterative extended Hiickel and the ab initio, limited basis set, Hartree-Fock calculations are capable of de-... 

The investigation of the response of macromolecules to external mechanical forces or to electromagnetic fields may basically contribute to our understanding of the structural and functional properties of these systems. The starting point of all studies of this kind is the proper description of the equilibrium (ground) state of the molecule without external fields. In our a priori calculations, the ground state energy is obtained in two steps as a zeroth order approximation the Hartree-Fock (HF) contribution is calculated by the ab initio crystal orbital method (1,2) and electronic correlation effects are included by perturbation theory afterwards. 

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