THEORETICAL AB-INITIO STUDY OF O-H VIBRATIONAL BAND IN GAS-PHASE GLYCINE CONFORMERS

The O-H vibrational band has been theoretically studied for the two mo st stable glycine conformers utilizing our variable effective mass app roach. The stretching frequencies of the O-H bond of the most stable g as-phase glycine conformers were predicted. Analytical expressions for the Hamiltonian matrix elements of the vibrational problem were deriv ed. A functional fit to the potential energy term was obtained based o n the electronic energies calculated at different O-H bond distances a t the MP2 level of theory. The calculated O-H stretching frequencies a re in good agreement with the low-temperature IR spectroscopic data. ( C) 1998. Published by Elsevier Science B.V. All rights reserved.