Ab initio calculations of the elastic, electronic, optical, and vibrational properties of PdGa compound under pressure

doi:10.1088/1674-1056/21/9/097102

摘要/Abstract

摘要： The structural, elastic, electronic, optical, and vibrational properties of cubic PdGa compound are investigated using the norm-conserving pseudopotentials within the local density approximation (LDA) in the frame of density functional theory. The calculated lattice constant has been compared with the experimental value and has been found to be in good agreement with experimental data. The obtained electronic band structures show that PdGa compound has no band gap. The second-order elastic constants have been calculated, and the other related quantities such as the Young's modulus, shear modulus, Poisson's ratio, anisotropy factor, sound velocities, and Debye temperature have also been estimated. Our calculated results of elastic constants show that this compound is mechanically stable. Furthermore, the real and imaginary parts of the dielectric function and the optical constants such as the electron energy-loss function, the optical dielectric constant and the effective number of electrons per unit cell are calculated and presented in the study. The phonon dispersion curves are also derived using the direct method.

关键词: PdGa, vibrational properties, optical properties, elastic constants

Abstract: The structural, elastic, electronic, optical, and vibrational properties of cubic PdGa compound are investigated using the norm-conserving pseudopotentials within the local density approximation (LDA) in the frame of density functional theory. The calculated lattice constant has been compared with the experimental value and has been found to be in good agreement with experimental data. The obtained electronic band structures show that PdGa compound has no band gap. The second-order elastic constants have been calculated, and the other related quantities such as the Young's modulus, shear modulus, Poisson's ratio, anisotropy factor, sound velocities, and Debye temperature have also been estimated. Our calculated results of elastic constants show that this compound is mechanically stable. Furthermore, the real and imaginary parts of the dielectric function and the optical constants such as the electron energy-loss function, the optical dielectric constant and the effective number of electrons per unit cell are calculated and presented in the study. The phonon dispersion curves are also derived using the direct method.

Key words: PdGa, vibrational properties, optical properties, elastic constants

中图分类号: (Density functional theory, local density approximation, gradient and other corrections)

71.15.Mb

71.20.-b (Electron density of states and band structure of crystalline solids) 63.20.D- (Phonon states and bands, normal modes, and phonon dispersion)

H. Koc, A. Yildirim, E. Deligoz. Ab initio calculations of the elastic, electronic, optical, and vibrational properties of PdGa compound under pressure[J]. 中国物理B, 2012, 21(9): 97102-097102.

H. Koc, A. Yildirim, E. Deligoz. Ab initio calculations of the elastic, electronic, optical, and vibrational properties of PdGa compound under pressure[J]. Chin. Phys. B, 2012, 21(9): 97102-097102.

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