Two-phonon resonances and bound-states in molecular crystals. II. Absorption coefficient

Abstract

For pt.I see ibid., vol.11, p.1283 (1978). Using the Green function obtained in pt.I, the author obtains explicit expression for the two-phonon absorption coefficient of internal modes of molecular crystals. This expression is compared with the IR transmission spectra of CO2, N2O and OCS crystals and excellent agreement is found, in terms of two-phonon bound-states and resonances, for both shape and intensity of the bands under consideration.