Ab initio molecular dynamics simulations on the structural change of liquid eutectic alloy Si15Te85 from 673 to 1373 k

Using ab initio molecular dynamics simulations and inherent structure formalism, the local atomic structure and electronic properties of liquid Si15Te85 alloy were studied at eight different temperatures from 673 to 1373 K. In comparison with available experimental data, our calculated structure factors are acceptable. With increasing temperature from 773 to 1173 K, the calculated total coordination number NTotal increases gradually in contrast to the behavior of a classical isotropic fluid. Our results of pair-correlation functions, bond-angle distribution functions and angular limited triplet correlation functions suggest that the temperature-dependence of the preserved sp3 hybridization of Si atoms and Peierls-type distorted local structure around Te atoms both play important roles in the structural change of Si15Te85 characterized by thermodynamic anomalies.