Vibrational spectra and quantum chemical investigations on nicotinium nitrate monohydrate single crystal for anti bacterial studies

Nicotinium Nitrate Monohydrate (NNM) was grown by slow evaporation method. The arrangment of the molecules and hydrogen bonding intractionsin the grown crystal were analyzed using single crystal XRD. The structure, functional groups (vibrational analysis) and electronic properties (Mulliken and HOMO-LUMO analysis) were calculated by the density functional theory (DFT)/B3LYP/wB97XD method using 6–311++G (d,p) basis set. Also, the binding energy and the effect of basis set superposition error (BSSE) on the ring motifs have been investigated. The intermolecular interactions and charge delocalization density of NNM crystal have been analyzed using NBO 3.1 program. The strength of intermolecular interaction was further analyzed by 3D Hirshfeld surface analysis using fingerprint plot. Improved solubility of the title crystal NNM shows an enhanced physio-chemical activity compared to pure vitamin B3 (Nicotinic acid). The antibacterial activity of NNM crystal increased against Staphylococcus aureus a gram-positive bacteria when compared with pure nicotinic acid.