Vibrational Spectral Studies of Nicotinium Picrate

This article describes the vibrational spectra of nicotinium picrate. The Infrared and Raman Spectra were recorded at room temperature for nicotinium picrate and the observed bands were assigned. In nicotinium picrate compound nicotinium is the cation and picrate forming the anion. The N−H···O and O−H···N hydrogen bonds were observed in both infrared and Raman spectra. The structure is also stabilized by C−H···O hydrogen bonding. These hydrogen bonds link the layers of cation with the layers of anions. Nicotinic acid is also known as 3-pyridine carboxylic acid. Picrate being the trinitrophenolate has the characteristic bands of phenol. The nitro group and the phenoxy group stretching are observed in both infrared and Raman spectra. These suggest that the picrate ion is unaffected by the presence of the cations. Factor group analysis has been made and the numbers of vibrational modes have been calculated. The tentative assignments of the observed bands are given.