Schiff bases, an aldehyde- or ketone-like compounds in which the carbonyl group is replaced by an imine or azomethine, are some of the most widely used organic compounds. In this study, the quantum mechanics calculations were performed on M(Chel) where M=Ni(II) and Chel= BAE (bis-acetylacetoneethylenediimine), BBE=bis(benzoyl acetone)ethylenediimine, BFE= bis(1,1,1-triflouroacetylacetone) ethylenediimine and BCE = bis(3-chloroacetylacetone) ethylenediimine) ligands using Gaussian 03 and hartree-fock theory (HF) at B3LYP/6-311G level in the gas phase and solution phase. The polarized continuum model (PCM) is used to calculate salvation energies. After optimizing, various parameters such as electrode potentials, energy gap, chemical hardness, chemical potential and electrophilicity in solvent (DMSO) have been calculated. It was found to be planar and four coordinate. Reduction potentials toward a given M(II) according to the Schiff base ligands changed in the trend: BAE >BCE >BFE.