Molecular orbital study of the dithiocyanate tetraamine nickel(II) complex

Abstract

The equilibrium geometry and the electronic structure of the high-spin and low-spin forms of Ni(NH 3) 4(NCS) 2 have been studied using the CNDO-UHF type of MO-LCAO-SCF method. The adiabatic potential surface was considered as a function of equatorial and axial interatomic distances in the NiN′ 4N″ 2 chromophore. The equilibrium geometry, taking into account these degrees of freedom, and the harmonic force constants were obtained for this complex as well as for the dissociation limit cases, namely for Ni(NH 3) 4 2+ and Ni(NCS) 2 complexes. The electronic structure is discussed in terms of molecular orbitals, the values of Wiberg indices, charge distributions, spin densities and the energy partitioning.