Synthesis, spectroscopic characterization and DFT calculations on N-(Phenylsulfonyl)-l-asparagine (NPLAS): A potential nonlinear optical material

Abstract

The N-(Phenylsulfonyl)-l-asparagine (NPLAS), which is a potential nonlinear optical material, was synthesized and its geometric structure was optimized to obtain its geometric parameters, vibration frequencies and electronic structures at Hartree-Fock (HF) and B3LYP level of density functional theory (DFT) with 6–311++G(d,p) basis set, using Gaussian 09W program. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the title molecule were calculated by using the gauge independent atomic orbital (GIAO), continuous set of gauge transformations (CSGT) and individual gauges for atoms in molecules (IGAIM) methods and were also compared with experimental values. The electronic properties HOMO and LUMO energies were calculated and analyzed. Potential energy surface scan, natural population analysis (NPA) and Mulliken’s atomic charges were also investigated using DFT and HF models. A detailed molecular picture and intermolecular interactions arising from hyperconjugative interactions and charge delocalization of the molecule were analyzed using natural bond orbital (NBO) analysis.