Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5424129 | Surface Science | 2010 | 10 Pages |
Abstract
We present vibrational dynamics and thermodynamics for the (1Â 0Â 0) surfaces of Cu, Ag, Pd, Pt and Au using a real space approach. The force field for these systems is described by density functional theory. The changes in the vibrational dynamics and thermodynamics from those in bulk are confined mostly to the first-layer. A substantial enhancement of the low-frequency end of the acoustic branch was found and is related to a loosening of the bond at the surface. The thermodynamics of the first-layer also show significant differences (higher heat capacity, lower free energy and higher mean vibrational square amplitudes) from what obtains in bulk. Comparing these results with those calculated using embedded-atom method potentials, we discovered that for Ag(1Â 0Â 0) and Cu(1Â 0Â 0), the two methods yield very similar results while for Pd(1Â 0Â 0), Pt(1Â 0Â 0) and Au(1Â 0Â 0) there are substantial differences.
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
Handan Yildirim, Abdelkader Kara, Talat S. Rahman, Rolf Heid, Klaus-Peter Bohnen,