Synthesis, Characterization, Non-Linear Optical, Molecular Electrostatic Potential and HOMO-LUMO Analysis Using DFT Study of Novel Chiral Symmetric Schiff Bases

摘要

Three new chiral diimine Schiff bases, 5,5'-methyIene-bis-salicylidene-α-rnethylbenzy]amine (2), 5,5'-methylenebis(2-((Z)-((1-(4-methoxyphenyl)ethyl)imino)methyl)phenol)(3), 5,5'-methylenebis(2-((Z)-((3,3-dirnethylbutan-2-yl)imino)methyl)phenol) (4) including symmetric imine type have been synthesized. The 5,5'-methylenebis-salicylaldehyde (1) used as the starting material for the obtained Schiff bases was confirmed by single crystal X-ray diffraction. Characterization of novel symmetric diimine Schiff bases have been done by means of elemental analysis, FT-IR, ~1H and ~(13)C NMR spectral studies. Theoretical electronic structure calculations of the B3LYP/6-311+g(d,p) level were performed to optimize the molecular geometry. The non-linear optical properties such as dipole moment, polarizability and first order hyperpolarizability of 1, 2, 3 and 4 were determined. The HOMO and LUMO energy gaps revealed that the energy gaps reflected the chemical activity of me molecules. To obtain chemical reactivity of the molecules, the molecular electrostatic potential surface maps were plotted over the optimized geometry of the molecules.