Pressure behaviour and thermal expansion of NiMnSb from first principles calculations

• Published in: Solid state communications Vol. 140; no. 5; pp. 251 - 255
• Main Author: Pugaczowa-Michalska, M.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.11.2006; Elsevier
• Subjects: A. Magnetically ordered materials; Condensed matter: structure, mechanical and thermal properties; D. Anharmonicity; D. Equation of states; D. Thermal expansion; Exact sciences and technology; Physics; Thermal expansion; thermomechanical effects and density; Thermal properties of condensed matter; Thermal properties of crystalline solids; D. Equation of states; 67.80.Gb; 74.62.Fj; 64.40.De; A. Magnetically ordered materials; 71.20.Lp; D. Anharmonicity; D. Thermal expansion; Nickel alloys; Antimony alloys; Grueneisen constant; Debye approximation; Lattice parameters; Thermal expansion; Electronic structure; Equations of state; Manganese alloys; A. Magnetically ordered materials; D. Equation of states; D. Anharmonicity; D. Thermal expansion; Thermal expansion coefficient; Density functional method; Bulk modulus; 71.20.Lp; 74.62.Fj; 64.40.De; 67.80.Gb
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2006.07.029

A computational study of the pressure and thermal behaviour of NiMnSb within the framework of density functional theory and the Debye–Grüneisen model is reported. The theoretical values of equilibrium lattice parameter, bulk modulus, its pressure derivative, Debye temperature, Grüneisen constant and coefficient of thermal expansion are estimated from electronic structure calculated by the full-potential nonorthogonal local-orbital minimum basis method (FPLO). The bulk modulus and its pressure derivative have been computed using the Murnaghan form of the equation of states. The volume–temperature dependence was obtained by minimisation of the free energy as a sum of the total energy of the rigid lattice and the free energy of the vibration lattice. The thermal expansion coefficient for the studied NiMnSb, obtained within the Debye theory including anharmonicity, is in good agreement with experimental results.