Generalized skeletal approximation in the analysis of vibrational spectra of polymers

A mathematical procedure is given for analyzing the low-frequency region of the vlbrational spectrum for a defective polymer; this reduces the order of the secular equation to the number of degrees of freedom of the atoms forming the skeleton. As a result, the matrices for the kinetic and potential energies become frequency-dependent, and they describe the vibrations of the skeleton at frequencies near zero, with the nodes bearing lumped masses equal to the masses of the repeating units. © 1979 Plenum Publishing Corporation.