Ab initio molecular dynamics studies of the structure and dynamics of molten SexTe1-x alloys

Abstract

We calculate the microscopic structure and dynamics of molten SexTe1-x alloys (x=0.3, 0.5, 0.7) at 748 K by means of ab initio molecular dynamics. We present results for the static and dynamic structure factors, diffusion coefficients, and frequency spectra, in addition to the electronic density of states. Both the results for the structural and dynamic properties are in relatively good agreement with the available experimental data, despite the known shortcomings of ab initio techniques for the limiting case x=0. The results also indicate that, as expected, the increase in the number of Te atoms augments the metallic character of the sample in close connection with a corresponding disruption of the Se chain network that dominates the structure of the condensed phases of pure selenium. © 2005 The American Physical Society.