Spectroscopic investigations, quantum chemical calculations, HOMO-LUMO and NBO/NLMO analysis of 4-pyridinecarbohydrazide.

The FT-IR and FT-Raman spectra of 4-pyridinecarbohydrazide have been recorded. The complete vibrational assignment and analysis of the fundamental modes was carried out using the experimental data and quantum chemical studies. The observed vibrational data were compared with the wavenumbers derived theoretically for the optimized geometry of the compound from the DFT-B3LYP gradient calculations employing 6-311++G(d,p) basis set. The (1)H and (13)C NMR chemical shifts have been simulated. Thermodynamic properties have been calculated at different temperatures. HOMO-LUMO energy gap has been calculated. The intramolecular contacts have been interpreted using Natural Bond Orbital (NBO) and Natural Localized Molecular Orbital (NLMO) analysis.