Molecular investigation and Vibrational analysis of some Pharmacological compounds Experimental and theoretical Approach

Abstract

In scientific research and technology, the growth of single crystals has enormous importance and many organic and inorganic materials are used in growth of crystals. Nicotinic acid (NIC), a vitamin B compound used for normal growth and maintenance of the body. It is found to posses many pharmaceutical applications mainly in the treatment of niacin deficiency. The presence of pyridine N atom and carboxylic acid groups in NIC tends to form organic crystals through non-covalent interactions. The present thesis work is focused on the growth and characterisation of derivative of the heterocyclic aromatic compound, nicotinic acid. Also, density functional (DFT) theory calculations were carried out by quantum chemical analysis with B3LYP/6-311++G(d,p) bais set. The experimental data obtained from solid crystalline state are compared with the calculated values. The solubility and antibacterial studies were done to enhance the physico chemical properties of the compound. Thesis comprises of four chapters. newlineFirst chapter gives the introduction of the compound and its applications. Also, the fundamentals of crystal growth method and the structure of crystal obtained through single crystal XRD are discussed. The procedure for structure determination and refinement are discussed. The precise study of intermolecular interactions and bonding between the atoms which control the property of the material are briefly discussed. Apart from XRD, the quantum chemical calculations are explained for optimization of structures and analyses the vibrational spectrum of the crystals. Hydrogen bondings and its rules are presented with necessary notations. Hirshfeld surface formations and its analyses are briefed. Vibrations of molecules and its spectral measurements are fundamentally described. The antibacterial activity by classical method like agar diffusion method is briefly discussed newline