STATISTICAL THERMODYNAMIC APPROACH TO VIBRATIONAL SOLITARY WAVES IN ACETANILIDE

We analyze the behavior of the macroscopic thermodynamic state of poly mers, centering on acetanilide. The nonlinear equations of evolution f or the populations and the statistically averaged field amplitudes of CO-stretching modes are derived. The existence of excitations of the s olitary wave type is evidenced. The infrared spectrum is calculated an d compared with the experimental data of Careri et al. [Phys. Rev. Let t. 51, 104 (1983)], resulting in a good agreement. We also consider th e situation of a nonthermally highly excited sample, predicting the oc currence of a large increase in the lifetime of the solitary wave exci tation. [S0031-9007(98)05407-6].