Vibrational spectra and thermodynamic analysis of metformin

Abstract

Metformin is one of the important anti-diabetic drugs to treat non-insulin dependent diabetes mellitus (NIDDM). Fourier transform infrared (FTIR) and Fourier transform Raman (FTR) spectra of metformin have been used for the molecular study. A satisfactory band assignment has been made on the fundamental modes of vibration. Employing the molecular mechanics method using MM3 force field, the theoretical vibrational frequencies and geometry parameters like bond lengths, bond angles etc are calculated and compared with the experimental frequencies. The observed frequencies are used to compute the thermodynamic functions, namely, the enthalpy, entropy, heats of formation, heat capacity using standard expressions at temperature 298 K and one atmospheric pressure.