First-principles investigations on structural and elastic properties of CaX (X=S, Se and Te) under high pressure

Abstract

An investigation on structural and elastic properties of CaX (X=S, Se and Te) under high pressure is conducted using first-principles calculations based on density functional theory with the plane wave basis set as implemented in the CASTEP code. Our results demonstrate that the sequence of the pressure-induced phase transition of the three compounds is the NaCl-type to the CsCl-type structure. The calculated structural and elastic parameters of CaX (X=S, Se and Te) agree well with the available experimental results and the previous theoretical data.

Keywords:

• ab initio calculations
• high pressure
• elastic property
• phase transition

Acknowledgements

This work was supported by China Postdoctoral Science Foundation (Grant No. 20090450924), the Doctoral Foundation of Hebei Normal University of Science and Technology (Grant No. 2008YB001), the National Natural Science Foundation of China (Grant Nos. 50771090 and 50821001), the State Key Program for Basic Research of China (Grant No. 2005CB724404) and the Program for Changjiang Scholars and Innovative Team (Grant No. IRT0650).