CONFORMATIONAL STUDY OF ALPHA-POLY(L-VALINE) - A VIBRATIONAL APPROACH

In continuation to our work on the oligomapping of the dispersion curv es of poly(L-valine) in beta form, the present work, is a study or nor mal modes and their dispersion in the alpha form. The Urey Bradley for ce field used in Wilson's GF matrix method has been transferred from t he beta form and refitted to explain the FTIR spectra. The characteris tic features or the dispersion curves involve repulsion with character exchange and tendency of certain pair of modes involving the motion o r C-alpha atom to come closer near the helix angle. Predictive value o f heat capacity is obtained from the density-of-states. It is observed that the mixed modes make the maximum contribution.