MONTE-CARLO SIMULATIONS OF THE ADSORPTION OF POTASSIUM ON A CU(111) SURFACE

Citation
L. Padillacampos et A. Torolabbe, MONTE-CARLO SIMULATIONS OF THE ADSORPTION OF POTASSIUM ON A CU(111) SURFACE, The Journal of chemical physics, 108(15), 1998, pp. 6458-6465
Citations number
19
Categorie Soggetti
Physics, Atomic, Molecular & Chemical
ISSN journal
00219606
Volume
108
Issue
15
Year of publication
1998
Pages
6458 - 6465
Database
ISI
SICI code
0021-9606(1998)108:15<6458:MSOTAO>2.0.ZU;2-4
Abstract
Monte Carlo simulations of the adsorption of potassium on a Cu(111) su rface at 80 K and coverages going from theta=0.13 ' to theta=0.26 mono layer are reported. The particles interact through an adsorbate-substr ate potential previously derived and through a classical adsorbate-ads orbate Morse-type potential. Interesting results concerning the nature of the adsorbed phase have been obtained: (a) We have found that the potassium adlayer is incommensurate under 1 ML coverage (theta=0.25), but it becomes commensurate at 1 ML, forming a p(2X2) adlayer with res pect to the Cu substrate. (b) A procedure to determine the distributio n of potassium on different adsorption sites in terms of theta has bee n developed with the result that top sites are the preferred sites for adsorption, although at low and medium coverages other sites are also occupied. At 1 ML only the top sites are occupied, in good agreement with the available experimental data. (C) 1998 American Institute of P hysics. [S0021-9606(98)00712-0].