Quantum mechanical study of the structure and spectroscopic (FT-IR, FT-Raman), first-order hyperpolarizability, NBO and HOMO–LUMO analysis of S-S-2 methylamino-1-phenyl propan-1-ol

Abstract

The experimental and theoretical vibrational spectra of S-S-2 methylamino-1-phenyl propan-1-ol (SSMPL). Fourier transform infrared (FTIR) and FT Raman spectra of SSMPL in the solid phase were recorded and analyzed. The molecular geometry, vibrational frequencies, infrared intensities, Raman activities and atomic charges were calculated using density functional theory calculation (B3LYP) with standard 6-31G(d,p) and high level 6-311++G(d,p) basis sets. Complete vibrational assignment and analysis of the fundamental modes of the compound were carried out using the observed FTIR and FT Raman data. The thermodynamic functions of the title compound were also performed by B3LYP with two basis sets 6-31G(d,p) and 6-311++G(d,p). Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. Using the method B3LYP, the dipole moment (μ), polarizability (α) and the hyperpolarizability (β) values of the investigated molecule has been computed. Total energy distribution (TED) was used for the assignment of Unambiguous vibrational fundamental modes. Finally, Simulated FTIR and FT Raman spectra of SSMPL showed good agreement with the observed spectra.