Science and Education Publishing Physics and Materials Chemistry 2372-7101 3 1 2015 07 15 Synthesis, X­Ray Crystallography and DFT Studies of Ni(II) Complex with Tetradentate 7 11 EN Salem El-t. Ashoor Chemistry Department, Faculty of Science, Misurata University, LIBYA Hana B. Shawish PMC2015312 10.12691/pmc-3-1-2 2015 05 24 2015 06 26 2015 07 15 The paper presents a combined experimental and computational study of new compound {Bis(2R)-2-hydroxy-3-(iminomethyl)cyclohexaol}benzene Nickel(II) complex. The structure of consists of isolated neutral molecules in which the nickel (II) center atom is situated in a slightly distorted square-planar surrounding, the complex was found as monoclinic space group P-1 with a = 12.133 (6), b=15.017 (7), c =15.393(7)Å, α = 74.17, β = 70.92 (5), γ = 70.08 and Z = 4. The complex has been characterized via single-crystal X-ray diffraction and then the conformation of the molecular structure in the ground state has been calculated using the density functional theory (DFT) methods with generalised gradient approximation (Becke)(LeeèCYang-Parr) GGA BLYP level of theory often being used to obtain more exact results and TZP basis sets, frontier molecular orbitals (FMO) were investigated theoretically. By using Dewar-Chatt-Duncanson model, as a basis of the molecular orbital (MO) analysis shown the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital LUMO.