Abstract
The formation and mobility of Li point defects in Li2B 4O7 are investigated theoretically with periodic quantum chemical calculations. Calculated defect formation energies obtained with a density functional theory/Hartree-Fock hybrid method and with the Perdew-Wang density functional method are compared. The basis set effect is investigated by comparison of results obtained with atom-centered basis functions and plane waves. With both methods only a moderate relaxation is observed for the atoms surrounding the Li defect position. The defect-induced change of electronic properties is investigated by calculating the density of states for the stoichiometric and defective supercells. The activation energy for the movement of a Li+ ion along the (001) direction is calculated. It is observed that Li+ ion migrates through a one-dimensional channel formed by the five-vertex lithium-oxygen (LiO5) polyhedra. The calculated activation energies are in excellent accord with experiment.
Original language | English |
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Pages (from-to) | 17518-17523 |
Number of pages | 6 |
Journal | Journal of Physical Chemistry B |
Volume | 110 |
Issue number | 35 |
Early online date | 15 Aug 2006 |
DOIs | |
Publication status | Published - 1 Sept 2006 |
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry