Ab-initio calculations of elastic constants and thermodynamic properties of LuAuPb and YAuPb half-heusler compounds

• Sukhwinder Singh^, , 
• Rajesh Kumar 

• Department of Physics, Panjab University, Chandigarh 160014, India

Received 31 March 2017, Revised 8 June 2017, Accepted 12 June 2017, Available online 13 June 2017

Abstract

In this work, density functional theory plane-wave pseudo potential method with generalized gradient approximation is used to investigate the elastic, mechanical, phonon and thermodynamic properties of LuAuPb and YAuPb compounds. The physical properties such as elastic constants, bulk modulus, shear modulus, Young's modulus, Poisson's ratio and shear anisotropy factor of both the compounds are calculated. The elastic properties of these compounds reveal that these compounds are mechanically stable. Further, the phonon dispersion curves prove that these compounds are also dynamically stable. The study of shear anisotropic factor gives purely anisotropic nature of these compounds. Pugh's and Frantsevich's ratio shows that both these compound exhibits ductile nature. The sound velocities and Debye temperature of these compounds are also estimated from elastic constants. Using the slack equation, the lattice thermal conductivity of these compounds is also estimated. At room temperature, LuAuPb attains low thermal conductivity as compared to YAuPb. At 300 K, the calculated values of specific heat capacity per atom at constant volume for LuAuPb and YAuPb compounds are 24.37 Jmol⁻¹ K⁻¹ and 23.95 Jmol⁻¹ K⁻¹ respectively. This is the first quantitative theoretical estimation of these properties.

To download the article click on the link below:


http://www.sciencedirect.com.sci-hub.cc/science/article/pii/S0925838817321308