Structural Stabilities and Optical Properties of BaX (X=S, Se and Te) under High Pressure
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摘要: 利用基于密度泛函的第一性原理,计算了高压下钡的硫化物(BaS、BaSe和BaTe)的结构相变和光学性质。计算结果表明,这些化合物的压致结构相变是从NaCl型结构转变为CsCl型结构;对于结构转变压力和金属化转变压力,BaS为8.57 GPa和45.4 GPa,BaSe为7.44 GPa和36.5 GPa,BaTe则分别为5.67 GPa和16.7 GPa。光学性质计算结果显示:随着压力的增加,静态介电常数0不断增加,介电常数虚部2的峰值向高能方向移动(蓝移)。Abstract: An investigation on the structural stabilities and optical properties of BaX (X=S, Se and Te) under high pressure was conducted using first-principles calculations based on density functional theory. The results show that the sequence of the pressure-induced phase transition of these compounds is from the NaCl-type (B1) to the CsCl-type (B2) structure. The structural transition pressure and the metallization pressure are 8.57 and 45.4 GPa for BaS, 7.44 and 36.5 GPa for BaSe, 5.67 and 16.7 GPa for BaTe, respectively. The calculation of the optical properties showed that almost all peaks of the imaginary part of dielectric constant (2) in the B1 and B2 structures shift towards high-energy region with increasing pressure (blue shift), and the static dielectric constant increases as the pressure increases.
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Key words:
- first-principles /
- structural transition /
- optical property /
- high pressure /
- dielectric constant
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Khenata R, Baltache H, Rrat M, et al. First-Principle Study of Structural, Electronic and Elastic Properties of SrS, SrSe and SrTe under Pressure [J]. Physica B: Condens Matter, 2003, 339(4): 208-215. Pandey R, Sivaraman S. Spectroscopic Properties of Defects in Alkaline-Earth Sulfides [J]. J Phys Chem Solids, 1991, 52(1): 211-225. Yamaoka S, Shinomura O, Nakazawa H, et al. Pressure-Induced Phase Transformation in BaS [J]. Solid State Commun, 1980, 33(1): 87-89. Grzybowski T A, Ruoff A L. High-Pressure Phase Transition in BaSe [J]. Phys Rev B, 1983, 27(10): 6502-6503. Grzybowski T A, Ruoff A L. Band-Overlap Metallization of BaTe [J]. Phys Rev Lett, 1984, 53(5): 489-492. Minomura S. Solid State Physics under Pressure [M]. 1st ed. Tokyo: Terra Scientific Press, 1985: 57-61. Weir S T, Vohra Y K, Ruoff A L. Pressure-Induced Metallization of BaSe [J]. Phys Rev B, 1987, 35(2): 874-876. Ross M, McMahan A K. Systematics of the sd and pd Electronic Transition at High Pressure for the Elements I through La [J]. Phys Rev B, 1982, 26(8): 4088-4093. Pourghazi A, Dadsetani M. Electronic and Optical Properties of BaTe, BaSe and BaS from First Principles [J]. Physica B: Condens Matter, 2005, 370(1-4): 35-45. Bouhemadou A, Khenata R, Zegrar F, et al. Ab Initio Study of Structural, Electronic, Elastic and High Pressure Properties of Barium Chalcogenides [J]. Comput Mater Sci, 2006, 38(2): 263-270. Charifi Z, Baaziz H, Hassan F E H, et al. High Pressure Study of Structural and Electronic Properties of Calcium Chalcogenides [J]. J Phys Condens Matter, 2005, 17(26): 4083-4092. Tuncel E, Colakoglu K, Deligoz E, et al. A First-Principles Study on the Structural, Elastic, Vibrational, and Thermodynamical Properties of BaX (X=S, Se, and Te) [J]. J Phys Chem Solids, 2009, 70(2): 371-378. Perdew J P, Burke K, Ernzerhof M. Generalized Gradient Approximation Made Simple [J]. Phys Rev Lett, 1996, 77(18): 3865-3868. Francis G P, Payne M C. Finite Basis Set Corrections to Total Energy Pseudopotential Calculations [J]. J Phys Condens Matter, 1990, 2(19): 4395-4404. Birch F. Finite Strain Isotherm and Velocities for Single-Crystal and Polycrystalline NaCl at High-Pressures and 300 Degrees K [J]. J Geophys Res, 1978, 83(4): 1257-1268. Ma Y, Eremets M, Oganov A R, et al. Transparent Dense Sodium [J]. Nature, 2009, 458(7235): 182-185. Ma Y, Oganov A R, Li Z, et al. Novel High Pressure Structures of Polymeric Nitrogen [J]. Phys Rev Lett, 2009, 102(6): 065501. Kalpana G, Palanivel B, Rajagopalan M. Electronic Structure and Structural Phase Stability in BaS, BaSe, and BaTe [J]. Phys Rev B, 1994, 50(17): 12318-12325. Weir S T, Vohra Y K, Ruoff A L. High-Pressure Phase Transitions and the Equations of State of BaS and BaO [J]. Phys Rev B, 1986, 33(6): 4221-4226. Kaneko Y, Morimoto K, Koda T. Optical Properties of Alkaline-Earth Chalcogenides. II. Vacuum Ultraviolet Reflection Spectra in the Synchrotron Radiation Region of 4~40 eV [J]. J Phys Soc Jpn, 1983, 52(12): 4385-4396. Zimmer H G, Winzen H, Syassen K. High-Pressure Phase Transitions in CaTe and SrTe [J]. Phys Rev B, 1985, 32(6): 4066-4070. Hamann D R, Schlter M, Chiang C. Norm-Conserving Pseudopotentials [J]. Phys Rev Lett, 1979, 43(20): 1494-1497. Saha S, Sinha T P. Electronic Structure, Chemical Bonding, and Optical Properties of Paraelectric BaTiO3 [J]. Phys Rev B, 2000, 62(13): 8828-8834.
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