Structural and electrical properties of Ga–Te systems under high pressure  

作　　者：Youchun Wang Fubo Tian Da Li Defang Duan Hui Xie Bingbing Liu Qiang Zhou Tian Cui 王友春;田夫波;李达;段德芳;谢慧;刘冰冰;周强;崔田(State Key Laboratory of Superhard Materials, College of Physics, Jilin University)

机构地区：[1]State Key Laboratory of Superhard Materials, College of Physics, Jilin University

出　　处：《Chinese Physics B》2019年第5期210-215,共6页中国物理B（英文版）

基　　金：Project supported by the National Key R&D Program of China(Grant Nos.2018YFA0305900 and 2016YFB0201204);the National Natural Science Foundation of China(Grant Nos.51632002,51572108,11574109,91745203,and 11634004);Program for Changjiang Scholars and Innovative Research Team in University,China(Grant No.IRT 15R23);National Fund for Fostering Talents of Basic Science,China(Grant No.J1103202)

摘　　要：First-principles evolutionary calculation was performed to search for all probable stable Ga–Te compounds at extreme pressure. In addition to the well-known structures of P6_3/mmc and Fm-3 m Ga Te and I4/m Ga_2 Te_5, several new structures were uncovered at high pressure, namely, orthorhombic I4/mmm GaTe_2 and monoclinic C2/m Ga Te_3, and all the Ga–Te structures stabilize up to a maximum pressure of 80 GPa. The calculation of the electronic energy band indicated that the high-pressure phases of the Ga–Te system are metallic, whereas the low-pressure phases are semiconductors. The electronic localization functions(ELFs) of the Ga–Te system were also calculated to explore the bond characteristics. The results showed that a covalent bond is formed at low pressure, however, this bond disappears at high pressure, and an ionic bond is formed at extreme pressure.First-principles evolutionary calculation was performed to search for all probable stable Ga–Te compounds at extreme pressure. In addition to the well-known structures of P6_3/mmc and Fm-3 m Ga Te and I4/m Ga_2 Te_5, several new structures were uncovered at high pressure, namely, orthorhombic I4/mmm GaTe_2 and monoclinic C2/m Ga Te_3, and all the Ga–Te structures stabilize up to a maximum pressure of 80 GPa. The calculation of the electronic energy band indicated that the high-pressure phases of the Ga–Te system are metallic, whereas the low-pressure phases are semiconductors. The electronic localization functions(ELFs) of the Ga–Te system were also calculated to explore the bond characteristics. The results showed that a covalent bond is formed at low pressure, however, this bond disappears at high pressure, and an ionic bond is formed at extreme pressure.

关 键 词：DENSITY FUNCTIONAL theory Ga–Te system electronic PROPERTY 

分 类 号：O521[理学—高压高温物理]