Accession Number : ADA185222

Title :   Pure Dephasing of a Vibrational Adbond.

Descriptive Note : Technical rept.,

Corporate Author : STATE UNIV OF NEW YORK AT BUFFALO DEPT OF CHEMISTRY

Personal Author(s) : Van Smaalen, Sander ; George, Thomas F

PDF Url : ADA185222

Report Date : Aug 1987

Pagination or Media Count : 45

Abstract : A theoretical study of the vibrational relaxation of the adbond between a physisorbed molecule and a crystalline substrate is presented. The bond between the admolecule and substrate is described as a one-dimensional Morse-oscillator. Using standard perturbation theory, expressions for the relaxation of the vibrational adbond due to its interaction with the substrate lattice vibrations are derived. Both energy relaxation and pure dephasing are considered. A numerical evaluation of the resulting expressions for the relaxation constants is given for a Debye spectrum for the phonons and for a surface phonon spectrum. The relative importance of pure dephasing and energy relaxation in determining the absorption linewidth is derived as a function of the fundamental frequency of the active mode.

Descriptors :   *MOLECULAR SPECTROSCOPY, *MOLECULAR VIBRATION, PHONONS, ADSORPTION, MORSE POTENTIAL, ABSORPTION SPECTRA, RELAXATION TIME, PERTURBATION THEORY, EIGENVECTORS, SURFACE CHEMISTRY

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE