A ®rst principles study of Rh on Mo(1 1 1) and W(1 1 1) surfaces
نویسندگان
چکیده
Using local density functional calculations, we studied the morphological changes of Mo(1 1 1) and W(1 1 1) upon the adsorption of an ultrathin ®lm of Rh. The unusual relaxations induced by Rh on Mo(1 1 1) and W(1 1 1) surfaces should be caused by competing several factors such as Smoluchowski smoothing eect, change of atomic interactions, and charge transfer between overlayer and substrate. It was found that both Rh/Mo(1 1 1) and Rh/W(1 1 1) can facet to f211g when the Rh coverage reaches one physical monolayer. The f211g facets should coexist with the (1 1 1) planar surfaces, which is substantially due to thermodynamic eects, and the onset annealing temperature for inducing facets of Rh/Mo(1 1 1) and Rh/W(1 1 1) should be higher than that for some other metal overlayers such as Pd. Ó 2001 Elsevier Science B.V. All rights reserved.
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