Strong electron correlation-induced Mott-insulating electrides of Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)  

作　　者：Ya Xu Lu Zheng Yunkun Zhang Zhuangfei Zhang QianQian Wang Yuewen Zhang Liangchao Chen Chao Fang Biao Wan Huiyang Gou 

机构地区：[1]Key Laboratory of Material Physics of Ministry of Education,School of Physics and Laboratory of Zhongyuan Light,Zhengzhou University,Zhengzhou 450052,China [2]School of Mechanical and Equipment Engineering,Hebei University of Engineering,Handan 056038,China [3]Center for High Pressure Science and Technology Advanced Research,Beijing 100094,China

出　　处：《Matter and Radiation at Extremes》2024年第3期74-82,共9页极端条件下的物质与辐射（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(Grant Nos.12204419 and 12074013)。

摘　　要：The presence of interstitial electrons in electrides endows them with interesting attributes,such as low work function,high carrier concentration,and unique magnetic properties.Thorough knowledge and understanding of electrides are thus of both scientific and technological significance.Here,we employ first-principles calculations to investigate Mott-insulating Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)electrides with Mn_(5)Si_(3)-type structure,in which half-filled interstitial electrons serve as ions and are spin-polarized.The Mott-insulating property is induced by strong electron correlation between the nearest interstitial electrons,resulting in spin splitting and a separation between occupied and unoccupied states.The half-filled antiferromagnetic configuration and localization of the interstitial electrons are critical for the Mott-insulating properties of these materials.Compared with that in intermetallic electrides,the orbital hybridization between the half-filled interstitial electrons and the surrounding atoms is weak,leading to highly localized magnetic centers and pronounced correlation effects.Therefore,the Mott-insulating electrides Ae_(5)X_(3)have very large indirect bandgaps(0.30 eV).In addition,high pressure is found to strengthen the strong correlation effects and enlarge the bandgap.The present results provide a deeper understanding of the formation mechanism of Mott-insulating electrides and provide guidance for the search for new strongly correlated electrides.

关 键 词：INTERMETALLIC FILLED occupied 

分 类 号：TN60[电子电信—电路与系统]