First principles study of the magnetism driven by cation defects in CeO_2:the important role of O2p states  

作　　者：路战胜 马东伟 张静 徐国亮 杨宗献 

机构地区：[1]College of Physics and Information Engineering and Henan Key Laboratory of Photovoltaic Materials,Henan Normal University,Xinxiang 453007,China [2]School of Mathematics and Information Science,North China University of Water Resources and Electric Power,Zhengzhou 450011,China

出　　处：《Chinese Physics B》2012年第4期537-542,共6页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 11174070, 10947001, and 11004066);the Innovation Scientists and Technicians Troop Construction Projects of Henan Province, China (Grant No. 104200510014);the Foundation for University Young Core Instructors of Henan Province, China (Grant No. 2009GGJS-044)

摘　　要：The magnetism driven by cation defects in undoped CeO2 bulk and thin films is studied by the density functional theory corrected for on-site Coulomb interactions （DFT＋U） with U = 5 eV for the Ce4f states and U = 7 eV for the O2p states. It is found that the Ce vacancies can induce a magnetic moment of the -4 gB/supercell, which arises mainly from the 2p hole state of the nearest neighbouring O atom （-1μB on per oxygen） to the Ce vacancy. The effect of the methodology is investigated, indicating that U = 7 eV for the O2p state is necessary to obtain the localized O2p hole state in defective ceria with cation vacancies.The magnetism driven by cation defects in undoped CeO2 bulk and thin films is studied by the density functional theory corrected for on-site Coulomb interactions （DFT＋U） with U = 5 eV for the Ce4f states and U = 7 eV for the O2p states. It is found that the Ce vacancies can induce a magnetic moment of the -4 gB/supercell, which arises mainly from the 2p hole state of the nearest neighbouring O atom （-1μB on per oxygen） to the Ce vacancy. The effect of the methodology is investigated, indicating that U = 7 eV for the O2p state is necessary to obtain the localized O2p hole state in defective ceria with cation vacancies.

关 键 词：MAGNETISM cation defect CEO2 density functional theory 

分 类 号：O472.5[理学—半导体物理]