Destabilization and diffusion of two-dimensional close-packed Pt clusters on Pt(111) during film growth from the vapor phase
1998 (English)In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 318, no 1-2, 57-60 p.Article in journal (Refereed) Published
Cluster migration is known to be an important process during film growth at elevated temperatures, but relatively little quantitative data is available. We have used molecular dynamics simulations to follow the dynamics of small two-dimensional Pt clusters on Pt(lll) at 1000 K. While close-packed Pt-7 heptamers are extremely stable structures, the addition of a single-cluster vacancy or an on-top adatom immediately results in intracluster bond breaking, reconfigurations, rotations, the introduction of stacking faults, and greatly enhanced cluster-diffusion rates. Mapping center-of-mass motion for total simulation times > 145 ns revealed increases in cluster velocities by more than an order of magnitude with cluster migration occurring primarily by concerted motion and a novel diffusion mechanism involving double shearing of dimers/trimers. Contrary to some previous reports, edge-atom diffusion plays only a minor role. (C) 1998 Elsevier Science S.A.
Place, publisher, year, edition, pages
1998. Vol. 318, no 1-2, 57-60 p.
destabilization; diffusion; Pt clusters
IdentifiersURN: urn:nbn:se:liu:diva-105976DOI: 10.1016/S0040-6090(97)01138-3OAI: oai:DiVA.org:liu-105976DiVA: diva2:712835
Symposium B on Epi-taxial Thin Film Growth and Nanostructures at the ICAM/EMRS Spring Conference,STRASBOURG, FRANCE, JUN 16-20, 1997.