Raman Spectra of Glycine and Their Modeling in Terms of the Discrete–Continuum Model of Their Water Solvation Shell

Abstract

Raman spectra of glycine in a crystalline form and in a water environment have been obtained. B3LYP/6-311++G(3df,2p) quantum-chemical calculations have shown that an adequate description of the Raman spectra of glycine is achieved using the discrete–continuum model of its water solvation shell. A model is proposed for the stabilization of the zwitterionic state of glycine involving the inclusion of a single water molecule that is hydrogen-bonded with the –СOO– and –NH $$_{3}^{ + }$$ groups. Calculations of the Raman spectra of glycine complexes Gly + nH2O (where n = 1–3), as well as of a glycine dimer, yield good agreement with experiment.