A theoretical investigation of the ground and a few excited states of the lithium cobalt-Schiff base complexes

Abstract

RHF-plus-correlation calculations have been performed on the ground and a few excited states of the complex Co(foracim)2Li, chosen as a model of the Co(Schiff base)Li complexes. The wave functions thus obtained have been subjected to Mulliken population analysis and analyzed in terms of the orbitals of the separate constituent fragments to bring out effects of electronic o-donation and a-back-donation between the cobalt atom and the ligand. The ground state of the isolated complex corresponds to an open-shell configuration of the Co/Li type and of AI symmetry, with the triplet and singlet components practically degenerate. A permanent magnetic moment of the order of at least 1.9 pB is predicted for the ground state of the complex. States corresponding to the configurations of the charge-transfer Col/Li+ type are higher in energy by more than 1 eV.