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A model of linear chain submonolayer structures. Application to Li/W(112) and Li/Mo(112)

F. Bagehorn·J. Lorenc·Cz. Oleksy
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Abstract

We propose a lattice gas model to account for linear chain structures adsorbed on (112) faces of W and Mo. The model includes a dipole-dipole interaction as well as a long-ranged indirect interaction. We have explicitly demonstrated that the periodic ground states depend on a competition between dipole-dipole and indirect interaction. The effect of temperature is studied within the molecular-field approximation. The numerical results show that for dipole-dipole interaction only, all long periodic linear chain phases are suppressed to low temperatures. However, when the long-range indirect interaction becomes important, the long-periodic linear chain phases start to fill up the phase diagram and develop a high thermal stability. Model parameters are chosen to reconstruct a sequence of long-periodic phases as observed experimentally for Li/Mo(112) and Li/W(112).

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F. Bagehorn, J. Lorenc, Cz. Oleksy. 1995-11-10. A model of linear chain submonolayer structures. Application to Li/W(112) and Li/Mo(112). https://doi.org/10.1016/0039-6028(95)01058-0

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