Anharmonic effects on monolayer phonons

DSpace/Manakin Repository

Anharmonic effects on monolayer phonons

Show full item record


Title: Anharmonic effects on monolayer phonons
Author: Bruch, L. W.; Novaco, Anthony D.
Abstract: The anharmonic frequency shifts of the phonons in monolayer solids of Ar/Pt(lll) and commensurate Xe/Pt(lll) are calculated with quasiharmonic perturbation theory and with self-consistent-phonon theory. Results from the two methods are in good agreement for Ar/Pt(lll). Uncertainties in the frequency shifts for the Ar/Pt(lll) modes are small compared to present uncertainties in the interaction model and in the experimental data. Anharmonic effects in the commensurate Xe/Pt(lll) solid at 80 K are large, both because of the small adatom-adatom force constants in this dilated lattice and because of the large degree of thermal excitation. A version of the improved self-consistent-phonon approximation is used for comparison to experimental data, and it is found that the anharmonic terms cause changes on the scale of adjustments in Xe-Pt forces previously found necessary to achieve fits of the harmonic theory to the data. The contribution of static adsorption-induced dipole moments to the monolayer lattice dynamics is analyzed and is found to be negligible for Xe/Pt(111).
URI: http://hdl.handle.net/10385/810
Date: 2000-02-15

Files in this item

Files Size Format View
Novaco-PhysicalReviewB-vol61-2000.pdf 94.19Kb PDF View/Open

This item appears in the following Collection(s)

Show full item record

Search LDR


Advanced Search

Browse

My Account