First-principles calculations of Mg2X (X = Si, Ge, Sn) semiconductors with the calcium fluorite structure*

The electronic structures of Mg2X (X = Si, Ge, Sn) have been calculated by using generalized gradient approximation, various screened hybrid functionals, as well as Tran and Blaha's modified Becke and Johnson exchange potential. It was found that the Tran and Blaha's modified Becke and Johnson exchange potential provides a more realistic description of the electronic structures and the optical properties of Mg2X (X = Si, Ge, Sn) than else exchange-correlation potential, and the theoretical gaps and dielectric functions of Mg2X (X = Si, Ge, Sn) are quite compatible with the experimental data. The elastic properties of Mg2X (X = Si, Ge, Sn) have also been studied in detail with the generalized gradient approximation, including bulk modulus, shear modulus, Young's modulus, Poisson's ratio, sound velocities, and Debye temperature. The phonon dispersions of Mg2X (X = Si, Ge, Sn) have been calculated within the generalized gradient approximation, suggesting no structural instability, and the measurable phonon heat capacity as a function of the temperature has been also calculated.

[1]  S. Pugh XCII. Relations between the elastic moduli and the plastic properties of polycrystalline pure metals , 1954 .

[2]  C. Rigaux Electronic Structure and Optical Properties , 1986 .

[3]  D. Lynch,et al.  Infrared Absorption in Mg2Ge , 1966 .

[4]  W. Kohn,et al.  Self-Consistent Equations Including Exchange and Correlation Effects , 1965 .

[5]  G. Scuseria,et al.  Hybrid functionals based on a screened Coulomb potential , 2003 .

[6]  D. G. Pettifor,et al.  Theoretical predictions of structure and related properties of intermetallics , 1992 .

[7]  Antonio Maria Cazzani,et al.  Extrema of Young’s modulus for cubic and transversely isotropic solids , 2003 .

[8]  M. Y. Au-Yang,et al.  Electronic structure and dielectric function of Mg2Si , 1968 .

[9]  W. Zhou,et al.  Structural, elastic and electronic properties of intermetallics in the Pt–Sn system: A density functional investigation , 2009 .

[10]  Robert G. Morris,et al.  Semiconducting Properties of Mg 2 Si Single Crystals , 1958 .

[11]  N. O. Folland Self-Consistent Calculations of the Energy Band Structure ofMg2Si , 1967 .

[12]  E. A. Gurieva,et al.  Highly effective Mg2Si1- xSnx thermoelectrics , 2006 .

[13]  D. Lynch,et al.  Pressure Coefficient of the Band Gap in Mg2Si, Mg2Ge, and Mg2Sn , 1967, October 1.

[14]  K. Burke,et al.  Rationale for mixing exact exchange with density functional approximations , 1996 .

[15]  R. D. Redin Semiconducting properties of Mg2Ge single crystals , 1957 .

[16]  A. Kahan,et al.  INFRARED ABSORPTION OF MAGNESIUM STANNIDE , 1964 .

[17]  J. Tani,et al.  Lattice dynamics of Mg2Si and Mg2Ge compounds from first-principles calculations , 2008 .

[18]  E. A. Gurieva,et al.  Highly effective Mg 2 Si 1 − x Sn x thermoelectrics , 2006 .

[19]  Peter M. H. Lee Electronic Structure of Magnesium Silicide and Magnesium Germanide , 1964 .

[20]  David J. Singh Electronic structure calculations with the Tran-Blaha modified Becke-Johnson Density Functional , 2010, 1009.1807.

[21]  J. Robertson,et al.  Screened exchange density functional applied to solids , 2010 .

[22]  M. Y. Au-Yang,et al.  Electronic Structure and Optical Properties of Mg 2 Si, Mg 2 Ge, and Mg 2 Sn , 1969 .

[23]  David J. Singh,et al.  Optical properties of ferroelectric Bi4Ti3O12 , 2010 .

[24]  Banggui Liu,et al.  Electronic structures and optical dielectric functions of room temperature phases of SrTiO3 and BaTiO3 , 2011 .

[25]  F. Aymerich,et al.  Pseudopotential band structures of Mg2Si, Mg2Ge, Mg2Sn, and of the solid solution Mg2(Ge, Sn) , 1970 .

[26]  Gustavo E. Scuseria,et al.  Erratum: “Hybrid functionals based on a screened Coulomb potential” [J. Chem. Phys. 118, 8207 (2003)] , 2006 .

[27]  R. Hill The Elastic Behaviour of a Crystalline Aggregate , 1952 .

[28]  Robert G. Morris,et al.  Semiconducting properties of Mg2Si single crystals , 1957 .

[29]  A. Reuss,et al.  Berechnung der Fließgrenze von Mischkristallen auf Grund der Plastizitätsbedingung für Einkristalle . , 1929 .

[30]  W. Scouler Optical Properties of Mg 2 Si, Mg 2 Ge, and Mg 2 Sn from 0.6 to 11.0 eV at 77°K , 1969 .

[31]  L. C. Davis,et al.  Elastic constants and calculated lattice vibration frequencies of Mg2Sn , 1966 .

[32]  The optical—electrical properties of doped β-FeSi2 , 2013 .

[33]  J. Walecka,et al.  Fundamentals of Statistical Mechanics: Manuscript and Notes of Felix Bloch , 2000 .

[34]  Burke,et al.  Generalized Gradient Approximation Made Simple. , 1996, Physical review letters.

[35]  R. Bechmann,et al.  Numerical data and functional relationships in science and technology , 1969 .

[36]  Haiyan Chen,et al.  Eutectic Microstructure and Thermoelectric Properties of Mg2Sn , 2010 .

[37]  Svane,et al.  Theoretical investigation of the isomer shifts of the 119Sn Mössbauer isotope. , 1987, Physical review. B, Condensed matter.

[38]  Matt Probert,et al.  First principles methods using CASTEP , 2005 .

[39]  P. Hohenberg,et al.  Inhomogeneous Electron Gas , 1964 .

[40]  Cohen,et al.  Structural, bonding, and electronic properties of IIA-IV antifluorite compounds. , 1993, Physical review. B, Condensed matter.

[41]  D. Wallace,et al.  Thermodynamics of Crystals , 1972 .

[42]  P. Blaha,et al.  Accurate band gaps of semiconductors and insulators with a semilocal exchange-correlation potential. , 2009, Physical review letters.

[43]  W. Qi,et al.  First principles calculations of electronic and optical properties of GaN 1- x Bi x alloys , 2014 .

[44]  B. Bouhafs,et al.  First‐principles calculations of the structural, electronic and optical properties of IIA–IV antifluorite compounds , 2005 .