Monte Carlo study of linear chain submonolayer structures. Application to Li/W(112)

[摘要] The lattice gas model for adsorption of alkaline elements on W(1 1 2) surface is studied by Monte Carlo simulations. The model includes dipole-dipole interaction as well as long-range indirect interaction. The numerical analysis of ground states shows that truncation of the indirect interaction even at 200 Angstrom may change a phase diagram, i.e., new long-periodic phases might occur. The phase diagram for Li/W(1 1 2) is constructed and chain structures (9 x 1), (6 x 1), (4 x 1), (3 x 1), and (2 x 1) are found to be stable at low temperatures. It is shown that the (4 x 1) phase melts through incommensurate phase. Role of thermal fluctuation is discussed by comparison of Monte Carlo results with mean field calculations. (C) 2003 Published by Elsevier B.V.

[发布日期] 2003-10-01

[关键词] Monte Carlo simulations;surface thermodynamics (including phase transitions);tungsten;low index single crystal surfaces