Theory of the Anomalous Rayleigh Dispersion at H/W(110) Surfaces

Claudia Bungaro; Stefano de Gironcoli; Stefano Baroni

doi:10.1103/PhysRevLett.77.2491

Theory of the Anomalous Rayleigh Dispersion at H/W(110) Surfaces

Claudia Bungaro, Stefano de Gironcoli, and Stefano Baroni

Phys. Rev. Lett. 77, 2491 – Published 16 September 1996

Abstract

The nature of the anomalies observed in the helium-atom scattering (HAS) and electron energy-loss (EELS) spectra of hydrogenated W(110) surfaces is investigated by calculating the full dispersion of the Rayleigh mode, using density-functional perturbation theory. We find excellent agreement between our calculations and the upper anomalous branch which is observed with both HAS and EELS. The lower branch—which is only detected by HAS—is instead not predicted. A hitherto unrecognized mechanism possibly responsible for the appearance of the second branch is proposed.

Received 16 May 1996

DOI:https://doi.org/10.1103/PhysRevLett.77.2491

Authors & Affiliations

Claudia Bungaro¹, Stefano de Gironcoli¹, and Stefano Baroni^1,2

¹INFM—Istituto Nazionale di Fisica della Materia and SISSA—Scuola Internazionale Superiore di Studi Avanzati, Via Beirut 2-4, 34014 Trieste, Italy
²CECAM—Centre Européen de Calcul Atomique et Moléculaire, ENS-Lyon, 46 Allée d'Italie, 69007 Lyon, France