Investigation on Spectral, Optical, Energy Level Designation of 6-(2-Phenylhydrazono) Tetrahydro-2-Thioxopyrimidin-4(1H)-one using Experimental and Theoretical Methods

Abstract

6 - (2 - phenylhydrazono) tetrahydro – 2-thioxo-pyrimidin – 4(1H)-one was synthesized and characterized using FT-IR, FT-Raman, NMR spectral techniques.  The FT-IR and FT-Raman spectra of 6-(2–phenylhydrazono)–tetrahydro–2–thioxo-pyrimidin-4(1H)-one have been recorded in order to study the normal modes of vibrations.  The theoretical wave number predictions were calculated by the density functional theory using the B3LYP function with 6-31G (d, p) basis set. Vibrational assignments were assigned with the help of potential energy distribution analysis.  The first order hyperpolarizability (β_o) calculation was performed to investigate the optical behaviour of   the compound.  The energy levels designated with respect to transition of electron from lower (σ) to higher level (Ï€).  The UV absorption at 238nm is designated as R-bands due to Ï€ - Ï€*.   Stability of  the molecule arising from hyper-conjugative interactions between donor (i) and acceptor (j) orbitals of the molecule.  Global reactivity descriptors and thermodynamic properties of PHTTO have also calculated based on DFT calculations.