Study of interatomic potential and thermal structural properties of β-Zn4Sb3

Highlights: ► The multi-body interatomic potentials of various models of β-Zn4Sb3 have been developed to describe atomic interactions. ► The radial distribution function shows that the 10% vacancy of Zn site leads to the disorder of β-Zn4Sb3. ► The 10% vacancy of Zn site is the main cause of the exceptional low thermal conductivity. -- Abstract: Previous experimental research shows that the disordered Zn atoms in β-Zn4Sb3 may have an important influence on its exceptionally low thermal conductivity and easily occurred phase transition. So the present work aims to study the influence of disordered Zn atoms on thermodynamics properties of β-Zn4Sb3 by using molecular dynamics (MD) method. Firstly, based on first principles calculation and experimental results, the interatomic potentials of β-Zn4Sb3 and MD analysis method are established, and the feasibility is verified. Then, the influence of disordered Zn atoms on thermal conductivity of β-Zn4Sb3 is studied in detail. The simulation results indicate that the 10% vacant Zn atoms is the main reason for the exceptionally low thermal conductivity of β-Zn4Sb3, and it seems that the interstitial Zn atoms have little effect on its thermal conductivity.