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Z. Naturforsch. 69a, 52 – 60
(2014)
doi:10.5560/ZNA.2013-0069
First-Principles Investigations on Structural, Elastic, and Thermodynamic Properties of Ce-La Alloys Under High Pressure
1 Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, College of Physical Science and Technology, Sichuan University, Chengdu 610064, China
2 Department of Physics and Electronic Information, Huaibei Normal University, Huaibei 235000, China
3 National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics, Chinese Academy of Engineering Physics, Mianyang 621900, China
Received April 30, 2013 / revised September 16, 2013 / published online November 21, 2013
Reprint requests to: Y. C.; E-mail:
ycheng@scu.edu.cn
The structural stability, thermodynamic, elastic, and electronic properties of cerium (Ce)-lanthanum (La) alloys were investigated for different Ce/La ratios under pressure by first-principles calculations using on-the-fly (OTF) pseudopotential and general gradient approximation (GGA). The ground-state properties of lanthanum and cerium obtained by minimizing the total energy agree favourably with other work. We derived the elastic constants, bulk modulus, and shear modulus of the La-Ce alloys for different Ce/La ratios. Using the quasi-harmonic Debye model, the thermodynamic properties of the La-Ce alloys including the thermal expansion coefficient α and heat capacity Cv are successfully obtained in the temperature range from 0 K to 1000 K. Furthermore, the electronic properties such as density of states and charge densities were also studied.
Key words: Ce-La Alloys; Elastic Properties; Thermodynamics Properties; Density Functional Theory.
PACS numbers: 71.15.Mb; 64.70.kd; 65.40-b; 65.40.De