Inclusion of the Coulomb Interaction in the Embedded-Atom Model: Lithium–Lead System

Resumo

A scheme is proposed for the incorporation of a screened Coulomb interaction into an embedded-atom model, which allows one to describe two- and multicomponent solutions with strong component interaction by the molecular dynamics method. The effective particle charges satisfy the electroneutrality condition and are determined via minimization of the total energy. The potentials of the pure components and fitted cross pair potentials are used in the calculations, with allowance for the electronic contributions to energy and pressure. For pairs of 1–2 in Li–Pb solutions (1 is for Li, and 2 is for Pb), a pair potential of the form 8–4 is proposed. Calculations were performed for several Li–Pb melts at zero pressure and temperatures up to 1000 K, as well as for a Li₁₇Pb₈₃ solution under shock compression at temperatures up to 25 000 K and pressures up to 470 MPa. The thermodynamic properties of the Li₁₇Pb₈₃ solution are presented in tabular form. The diffusion and structural properties of this and other solutions, the Grüneisen coefficients, and the Hugoniot adiabat are also calculated.