Self consistent Shaw Optimized Model Potential Application to the determination of structural and atomic transport properties of liquid alkaline metals by molecular dynamics simulations.

Nadra Harchaoui (1) , Slimane Hellal (1) , Jean-Georges Gasser (2) , Benoit Grosdidier (2)

1 Laboratoire de Physique et Chimie Quantique
2 LPMD - Laboratoire de Physique des Milieux Denses

In this paper, we develop the "first-principle" Shaw full-nonlocal and energy-dependent Optimized Model Potential (OMP) Phys. Rev. 174, 1968. Contrarily to the original paper, we obtain the OMP parameters in selfconsistent manner that doesn't ask for the knowledge of experimental values of the ionization and cohesive energies. To our knowledge it is the first time that this method is used for effective potential calculations. As an application to Li, Na, and K alkaline metals, we used OMP pseudopotential-based interactions between ions to carry out standard molecular-dynamics simulation. In these calculations, we first check the ionic structure for the liquid state at temperature near the melting point. Same accurate calculations, but for the atomic transport properties, predict the temperature dependence of the self-diffusion coefficients. Our theoretical results are in overall agreement with the available experimental measurements. Thus, one can have some confidence in the ability of the Optimized Model Potential to give a good representation of the physical properties of these alkaline ions in liquid environment.

Mots clés: Physical Sciences

Nadra Harchaoui, Slimane Hellal, Jean-Georges Gasser, Benoit Grosdidier. Self consistent Shaw Optimized Model Potential Application to the determination of structural and atomic transport properties of liquid alkaline metals by molecular dynamics simulations.. Philosophical Magazine, 2010, 90 (10), pp.1307-1326. ⟨10.1080/14786430903520757⟩. ⟨hal-00581010⟩