Stability of lithium in {alpha}-rhombohedral boron
- Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)
The stability of lithium atoms in {alpha}-rhombohedral boron was studied by the density functional theory and Car-Parrinello molecular dynamics (MD) simulations. At a low Li concentration (1.03 at%), a Li atom at the center of the icosahedral B{sub 12} site (the I-site) was found to be metastable, and the potential barrier was estimated at 775{+-}25 K (=67{+-}25 meV). Over 800 K, Li atoms began to escape from the B{sub 12} cage and settled at the tetrahedral site (the T-site) or at the octahedral site (the O-site). Li at the T-site was also metastable below 1400 K, and Li at the O-site was energetically the most favorable. At a high Li concentration (7.69 at%), the I-site changed to an unstable saddle point. The T-site was still metastable, and the O-site was the most stable. Regardless of concentration, MD simulations showed that Li atoms at the O-site never jumped to other sites below 1400 K. The migration of Li would be very slow below this temperature.
- OSTI ID:
- 20905446
- Journal Information:
- Journal of Solid State Chemistry, Vol. 179, Issue 9; Conference: 15. international symposium on boron, borides and related compounds, Hamburg (Germany), 21-26 Aug 2005; Other Information: DOI: 10.1016/j.jssc.2006.01.026; PII: S0022-4596(06)00030-2; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
Similar Records
Electronic structures, total energies, and optical properties of. alpha. -rhombohedral B sub 12 and. alpha. -tetragonal B sub 50 crystals
First-principles study of the electronic structures of alpha-rhombohedral boron codoped with lithium and oxygen