Local orientational order in binary liquid Li-In alloys

Abstract

The local orientational order in binary liquid Li-In alloys at a constant temperature has been systematically studied using molecular dynamics simulations combined with potential mapping techniques. The generalized non-local model pseudopotential theory has been chosen as the fundamental theory for our calculation. Both the orientational order parameters and pair analysis approach have been adopted to examine the characterization of structures in binary liquid Li-In alloys. It demonstrates that the mapping procedure produces a significant image enhancement of the short-range order, and the third-order invariant of the spherical harmonics is much more sensitive to the icosahedral symmetry than is the quadratic invariant. In addition, the bonded pairs with various symmetries, icosahedra, defective icosahedra, etc., formed in liquid Li-In alloys are also examined and the relationship between these quantities and compositions are investigated. The results further show that distributions of the attractive part of the potentials play an important role in characterizing liquid structures. Finally, a detailed discussion of the results has been given.