Phonon dispersion and heat capacity of poly(l-aspartic acid)

Abstract Normal modes and their dispersion are reported for the α-helical form of poly( l -aspartic acid) which is an important polypeptide used in the sustained release of drugs. Characteristic features of dispersion curves such as bunching and repulsion are discussed. Heat capacity is derived from the dispersion curves via density-of-states and compared with the available experimental data on sodium salt of the polymer.

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