Title :
Ab-initio investigation of a short range order and ionic conductivity in the La-Li-TiO3 system
Author :
Timoshevskii, A.N. ; Kalkuta, S.A.
Author_Institution :
Inst. of Magnetism, Nat. Acad. of Sci., Kiev, Ukraine
Abstract :
We have used ab-initio FLAPW method for the investigation of atomic and electronic structure of La0.5Li0.5TiO3 compound. We have carried out the set of total energy calculations with different Li atom location. It was determined that in this compound, a tetragonal crystal structure in which La atoms are alternated with Li atoms is energetically efficient. It is shown that a total energy minimum has been reached when Li atoms are centered on the faces of the cube formed by Ti atoms. We have derived a new formula describing lanthanum-lithium ionic conductors: La(23-x)/Li3x□3(1-x)TiO3. Dependence of the number of lithium vacancies on La and Li concentration for different ordering of these atoms was determined. We have determined possible Li atoms diffusion ways, and calculated the energy barriers too.
Keywords :
APW calculations; ab initio calculations; band structure; crystal faces; crystal structure; diffusion; ionic conductivity; lanthanum compounds; lithium compounds; short-range order; total energy; vacancies (crystal); La atoms; La concentration; La-Li-TiO3 system; La0.5Li0.5TiO3; Li atom location; Li atoms diffusion; Li concentration; Ti atoms; ab initio full potential linearised APW method; atomic structure; crystal cube faces; electronic structure; energy barriers; ionic conductivity; lanthanum lithium ionic conductors; lithium vacancies; short range order; tetragonal crystal structure; total energy calculations; Atomic layer deposition; Atomic measurements; Conductivity; Conductors; Convergence; Energy barrier; Geometry; Lanthanum; Lithium; Wave functions;
Conference_Titel :
Solid Dielectrics, 2004. ICSD 2004. Proceedings of the 2004 IEEE International Conference on
Print_ISBN :
0-7803-8348-6
DOI :
10.1109/ICSD.2004.1350504
