Ab initio molecular orbital calculations of the cobalt porphine complex. I. LCAO SCF MO calculation of low-spin, high-spin, and π-ionized states of Co-porphine

摘要: Ab initioLCAO SCF MO calculations are carried out on planar Co-porphine with a basis set of roughly double zeta quality for Co and N single C H. The net charge the overlap population between them 1.78, −0.57, 0.06, respectively, in 2A1g, state, which is known to be ground state by experiment. bonding this complex thus largely ionic. first second calculated ionization potentials 6.51 6.77 eV, reasonable agreement observed 6.44 6.62 eV Ni-tetraphenylporphine. CI within framework ligand field theory also performed. order five lowest states 4B2g ≈ 4Eg, 4A2g, 4Eg from below not semiempirical 2A1g 4B2G, 2Eg, determined Lin.