Variation of equation of state parameters in the Mg2(Si 1-xSnx) alloys

Pulikkotil, Jiji Thomas Joseph; Alshareef, Husam N.; Schwingenschlögl, Udo

Variation of equation of state parameters in the Mg2(Si 1-xSnx) alloys

Type

Article

Authors

Pulikkotil, Jiji Thomas Joseph
Alshareef, Husam N.

Schwingenschlögl, Udo

KAUST Department

Computational Physics and Materials Science (CPMS)
Functional Nanomaterials and Devices Research Group
Material Science and Engineering Program
Physical Science and Engineering (PSE) Division

Online Publication Date

2010-08-03

Print Publication Date

2010-09-08

Date

2010-08-03

Abstract

Thermoelectric performance peaks up for intermediate Mg2(Si 1-x:Snx) alloys, but not for isomorphic and isoelectronic Mg2(Si1-xGex) alloys. A comparative study of the equation of state parameters is performed using density functional theory, Green's function technique, and the coherent potential approximation. Anomalous variation of the bulk modulus is found in Mg2(Si1-xSn x) but not in the Mg2(Si1-xGex) analogs. Assuming a Debye model, linear variations of the unit cell volume and pressure derivative of the bulk modulus suggest that lattice effects are important for the thermoelectric response. From the electronic structure perspective, Mg2(Si1-xSnx) is distinguished by a strong renormalization of the anion-anion hybridization. © 2010 IOP Publishing Ltd.

Citation

Pulikkotil, J. J., Alshareef, H. N., & Schwingenschlögl, U. (2010). Variation of equation of state parameters in the Mg2(Si1 −xSnx) alloys. Journal of Physics: Condensed Matter, 22(35), 352204. doi:10.1088/0953-8984/22/35/352204