Libronndash;phonon coupling effect on the infrared absorption spectra of molecules trapped in matrices

摘要

The libronndash;phonon coupling (LPC) model is used to calculate the IR absorption coefficient of diatomic molecules trapped in solid matrices at low temperatures. The coupling between the collective motions of the crystal and the molecule librationhyphen;type motion is at the basis of the LPC model. This coupling results in temperature dependent shifts and broadening of the spectral lines even in the low temperature regime. The near IR experimental spectra of CO in Ne, Ar, Kr, and Xe matrices are successfully interpreted with the present theory. The strength of the libronndash;phonon coupling and other constants pertaining to the theory are reported. The far IR spectra is predicted as well.