Molecular Interaction Studies between Methylamine and 2-Nitrobenzoic Acid by Quantum Chemical Calculation (FT-IR, FMO, GCRD, MEP, NLO) and Dielectric Relaxation Analysis

Abstract

The FTIR spectrum of methylamine with 2-nitrobenzoic acid (ma2nba) in liquid phase is recorded and the comprehensive vibrational assignments and PED is attained by the vibrational energy distribution analysis. Ma2cba was theoretically optimized and FMO, nonlinear optical, molecular surfaces and comparison between Mulliken and natural charges were also performed by DFT method with B3LYP/6-311++G(d,p) basis set. The charge transfers in the molecule confirmed by the HOMO and lowest LUMO. Dielectric relaxation parameters like dielectric constant, dielectric loss, average and overall relaxation time, molar free energy of activation for viscous flow and the molar free energy of dielectric relaxation of ma2nba have been calculated over five different molar ratios (1:3, 1:2, 1:1, 2:1, 3:1) at room temperature by Higasi's method. These parameters are inferred in terms of molecular association and dipolar orientation. Moreover, the relaxation time found maximum at 1:1 molar ratio.