Hybridized nearly-free-electron tight-binding-bond approach to interatomic forces in disordered transition-metal alloys. II. Modeling of metallic glasses.

Abstract

We present an atomistic simulation of the structure of transition-metal glasses based on inter-atomic forces derived from quantum theory. Using the inter-atomic potentials calculated within the hybridized nearly-free-electron tight-binding-bond theory introduced in the preceding paper, we construct models for Ni-Y, Ni-Zr, Ni-Nb, Ni-Ti, and Ni-V glasses using a molecular-dynamics quench. The results are in good agreement with the most accurate diffraction data. The analysis of the simulation data demonstrates a clear trend from trigonal-prismatic to polytetrahedral local order and from strong to moderate chemical order in the series Ni-Y, Ni-Zr, and Ni-Nb. Within a given system, the trend is from trigonal prismatic to polytetrahedral, and towards increasing chemical order with increasing Ni content. The correlation of the structural trend with the characteristic variation in the electronic structure is established.