Lattice contraction of cerium hydrides from first-principles LDA + U calculations
Ce can be loaded with H forming complicated continuous solid solution and compounds,and causing remarkable electronic-structure changes.First-principles pseudopotential plane wave method with adding a Hubbard parameter U for considering the strong Coulomb correlation between localized 4f electron is employed to investigate the electronc and structural properties of stoichiometric and nonstoichiometric face-centered cubic (fcc) Ce hydrides (CeHx,x =2,2.25,2.5,2.75 and 3,respectively.).The most remarkable result is the decreasing trend of the calculated lattice parameters with increasing H composition,which is resulted from the associated effects of the enhanced chemical bonding owing to the participation of Ce 5d electron and,the size effects owing to the small H atomic radius and the large volume of octahedral interstice thus in favor of reducing the atomic distance for the formation of chemical bonding between Ce and octahedral H atoms.
Cerium hydride Density functional theory Strongly-correlated electron system Crystal structure
B.Y.Ao X.L.Wang P.Shi P.H.Chen X.Q.Ye X.C.Lai J.J.Ai T.Gao
Science and Technology on Surface Physics and Chemistry Laboratory, P.O.Box 718-35, Mianyang 621907, Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
国际会议
南京
英文
320-325
2012-05-13（万方平台首次上网日期，不代表论文的发表时间）