Terahertz Spectroscopy Studies of Solid-State Salicylic Acid

Abstract

Molecular and lattice vibration frequencies of solid-state salicylic acid were studied in the Terahertz (THz) and Mid-Infrared (Mid-IR) ranges. The calculation of the THz and Mid-IR spectra of salicylic acid which was based on the solid-state density functional theory (DFT) was carried out. Experimental studies were conducted by THz absorbance spectroscopy and Fourier transform infrared spectroscopy (FTIR) methods. Vibrations revealed in “finger-print” spectrum of salicylic acid were compared with the typical vibrations of groups of atoms that make up organic molecules.