OBSERVATION OF 2 DIFFUSION MODES OF A RE-IR DIMER-VACANCY COMPLEX ON THE IR(001) SURFACE AND THEIR DIFFUSION MECHANISMS

Authors
Citation
Cl. Chen et Tt. Tsong, OBSERVATION OF 2 DIFFUSION MODES OF A RE-IR DIMER-VACANCY COMPLEX ON THE IR(001) SURFACE AND THEIR DIFFUSION MECHANISMS, Physical review letters, 72(4), 1994, pp. 498-501
Citations number
16
Categorie Soggetti
Physics
Journal title
ISSN journal
00319007
Volume
72
Issue
4
Year of publication
1994
Pages
498 - 501
Database
ISI
SICI code
0031-9007(1994)72:4<498:OO2DMO>2.0.ZU;2-C
Abstract
A Re-Ir dimer-vacancy complex can be formed on an Ir(001) surface when the surface is heated to approximately 240 K with a Re atom vapor dep osited on it. Above approximately 210 K, the geometrical center of thi s complex can displace by one step of the substrate by an exchange dis placement of its Ir atom with a substrate Ir atom. This mechanism conf ines the movement of the complex to four nearest-neighbor sites of the substrate lattice. Only above approximately 235 K can the complex mov e out of these four sites by a combined hopping-exchange mechanism. Ab ove approximately 280 K, the Re-Ir dimer can dissociate. Upon dissocia tion, the Re atom will combine with the vacancy and self-diffusion of Ir will then occur.