p轨道占位库仑排斥对Mg2Sn电学性质的影响
Effects of p-Orbital On-Site Coulumb Repulsion on the Electronic Properties of Mg2Sn
DOI: 10.12677/CMP.2014.34006, PDF, HTML, 下载: 3,169  浏览: 12,165  国家自然科学基金支持
作者: 张 钰, 孔龙娟, 刘光华：天津工业大学理学院，天津；强 凌：北京大学物理学院，北京
关键词: GGA + U；占位库仑排斥；电学性质；GGA + U； On-Site Coulumb Repulsion； Electronic Properties
摘要: 利用基于密度泛函理论的广义梯度近似方法计算了Mg2Sn的能带结构、能态密度、差分电荷密度和介电函数。为了考虑Sn中5p轨道的强电子关联效应，我们采用GGA + U的方法计算Mg2Sn的电学性质。当有效U值为0 eV时，Mg2Sn带隙为负，与实验值相差较大。当有效U值为1.88eV时，间接带隙为0.30 eV，与实验值吻合较好。差分电荷密度的计算表明Mg2Sn中Sn-Sn键相对于Sn-Mg键有着较强的共价性，符合实际情况，介电函数的计算结果也与实验结果基本一致。这些证实p轨道占位库仑排斥对Mg2Sn的电学性质有着较大的影响。
Abstract: The band structure, density of states, electron density difference and dielectric function of Mg2Sn are investigated systematically by using the generalized gradient approximation based on density functional theory. To describe the strong electron correlation in the Sn 5p states, the GGA plus on-site repulsion method (GGA+U) is used in the electrical properties calculation of Mg2Sn. It is found that the band gap is negative with the effective U value of 0 eV, which is quite different from the experimental result. As the effective U value of 1.88 eV is considered, the compound is a semi-conductor with an indirect band gap of 0.30 eV, which agrees with the previous experimental ob-servation satisfactorily. The calculations of electron density difference show that the covalent bond between Sn-Sn is stronger than the covalent bond between Sn-Mg, which is accordant with the practical situation. The calculation of dielectric function agrees well with the experimental result, too. The important influence of the p-orbital on-site Coulumb repulsion for the electronic properties of Mg2Sn is confirmed.
文章引用：张钰, 孔龙娟, 强凌, 刘光华. p轨道占位库仑排斥对Mg2Sn电学性质的影响[J]. 凝聚态物理学进展, 2014, 3(4): 39-45. http://dx.doi.org/10.12677/CMP.2014.34006

参考文献

[1] Bougreios, J., Tobola, J., Wiendlocha, B., Chaput, L., Zwolenski, P., Recour, Q. and Scherrer, H. (2013) Study of elec-tion, phonon and crystal stability versus thermoelectric properties in Mg2X(X = Si, Sn) compounds and their alloys. Functional Materials Letters, 6, 1340005.
[2] Noda, Y., Kon, H., Furukawa, Y., Otsuka, N., Nishida, I.A. and Ma-sumoto, K. (1992) Temperature dependence of thermoelectric properties of Mg2Si0.6Ge0.4. Materials Transactions. JIM, 33, 851-855.
[3] Snyder, J.G. and Toberer, E.S. (2008) Complex thermoelectric materials. Nature Materials, 7, 105-114.
[4] Daniel, K., Bed, P., Hsien-Ping, F., Caylor, J.C., Yu, B., Yan, X., Ma, Y., Wang, X.W., Wang, S.Z., Muto, A., Kenneth, M., Matteo, C., Ren, Z.F. and Chen, G. (2011) High-performance flat-panel solar thermoelectric generators with high thermal concentration. Nature Materials, 10, 532-538.
[5] Yu, F., Sun, J.X. and Chen, T.H. (2011) High-pressure phase transitions of Mg2Ge and Mg2Sn: First-principles calculations. Physica B, 406, 1789-1794.
[6] Kutorasinski, K., Wiendlocha, B., Tobola, J. and Kaprzyk, S. (2014) Importance of relativistic effects in electronic structure and thermopower calculations for Mg2Si, Mg2Ge, Mg2Sn. Physical Review B, 89, 115205.
[7] Stella, A., Brothers, A.D., Hopkins, R.H. and Lynch, D.W. (1967) Pressure coefficient of the band gap in Mg2Si, Mg2Ge, and Mg2Sn. physica Status Solidi, 23, 697-702.
[8] Premlata, P. and Sankar, P.S. (2011) First prin-ciples study of electronic,elastic and lattice dynamical properties of Mg2X (X = Si, Ge and Sn) compounds. Indian Journal of Pure & Applied Physics, 49, 692-697.
[9] Buchenauer, C.J. and Cardona, M. (1971) Raman Scattering in Mg2Si, Mg2Ge, and Mg2Sn. Physical Review B, 3, 2504-2507.
[10] Scouler, W.J. (1969) Optical properties of Mg2Si, Mg2Ge and Mg2Sn from 0.6 to 11.0 eV at 77 degK. Physical Review, 178, 1353-1357.
[11] Blunt, R.F., Frederikse, H.P.R. and Hosler, W.R. (1955) Electrical and optical properties of intermetallic compounds IV magnesium stannide. Physical Review, 100, 663-666.
[12] Karazhanov, S.Z., Ravindran, P., Kjekshus, A., Fjellvag, H., Grossner, U. and Svensson, B.G. (2006) Coulomb correlation effects in zinc monochalcogenides. Journal of Applied Physics, 100, Article ID: 043709.
[13] Droghetti, A., Pemmaraju, C.D. and Sanvito, S. (2008) Predicting d0 magnetism: Self-interaction correction scheme. Physical Review B, 78, Article ID: 140404(R).
[14] Vladimir, I.A., Jan, Z. and Ole, K.A. (1991) Band theory and Mott insulators: Hubbard U instead of Stoner I. Physical Review B, 44, 943-954.
[15] Ylvisaker, E.R., Singh, R.R.P. and Picktt, W.E. (2010) Orbital order, stacking defects, and spin fluctuations in the p-electron molecular solid RbO2. Physical Review B, 81, Article ID: 180405(R).
[16] Coey, J.M.D. (2005) d0 ferromagnetism. Solid State Sciences, 7, 660-667.
[17] Kovacik, R. and Ederer, C. (2009) Correlation effects in p-electron magnets: Electronic structure of RbO2 from first principles. Physical Review B, 80, Article ID: 140411.
[18] Mim, K., Kim, B.H., Choi, C.H. and Min, B.I. (2009) Antiferromagnetic and structural transitions in the superoxide KO2 from first principles: A 2p-electron system with spin-orbital-lattice coupling. Physical Review B, 81, Article ID: 100409(R).
[19] Deng, X.Y., Liu, G.H., Jing, X.P. and Tian, G.S. (2014) On-site correlation of p-electron in d10 semiconductor zinc oxide. International Journal Quantum Chemistry, 114, 468-472.
[20] Duman, S., Tutuncu, H.M., Bagci, S. and Srivastava, G.P. (2007) Ab initio determination of structural and dynamical properties of Mg2Sn. AIP Conference Proceedings, 899, 247-248.
[21] Segall, M.D., Lindan, P.L.D., Probert, M.J., Pickard, C., Hasnip, P.J., Clark, S.J. and Payne, M.C. (2002) First-prin- ciples simulation: Ideas, illustrations and the CASTEP code. Journal of Physics-Condensed Matter, 14, 2717- 2744.
[22] 李鹏博, 潘荣凯, 马丽, 王明辉, 卞楠, 唐壁玉, 彭立明, 丁文江 (2014) Mg2Sn的弹性性能和电子结构的第一性原理计算. 广西大学学报(自然科学版), 3, 479-483.
[23] Wang, J.Y. and Zhou, Y.C. (2004) Polymorphism of Ti3SiC2 ceramic: First-principles investigations. Physical Review B, 69, Article ID: 144108.
[24] Ravindran, P., Fast, L., Korzhavyi, P.A., Johansson, B., Wills, J. and Eriksson, O. (1998) Density functional theory for calculation of elastic properties of orthorhomcic crystals: Applications to TiSi. Journal of Applied Physics, 84, 4891- 4904.
[25] 沈学础 (2002) 半导体光谱和光学性质. 科学出版社，北京.
[26] 方容川 (2001) 固体光谱学. 中国科学技术大学出版社，合肥.
[27] Au-Yang, M.Y. (1969) Electronic structure and optical properties of Mg2Si, Mg2Ge, and Mg2Sn. Physical Review, 178, 1358-1364.

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