Molecular Orbital Interpretation on the Inhibitory Effect of the Ni(II) Complexes with Polyamines and Imidazole Derivatives

Quantum chemical quantities, enthalpy of formation(), HOMO and LUMO energy, and dipole moment() were acquired by AM1, PM3, and ZINDO/1 methods for polyamines and imidazole derivatives. The investigation of the inhibitory activity on some Ni(II) complexes with polyamines and imidazole derivatives is performed by ZINDO/1 calculations. It was found that experimental inhibitory activity(IA) appeared when the value of net charge and enthalpy of formation were over 0.03 and -300 eV, respectively for Ni(II) complexes. These results showed that the Ni(II) complexes have exception on the following very unstable compounds: square pyramidal [Ni(dpt)(tn)])](dpt=3,3'-diaminodipropylamine)(tn=1,3-diaminopropane) and distorted tetrahedral [Ni(N-PropIm))(NCS))](N-PropIm=N-Propylimidazole).