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Burbano, M., Carlier, D., Boucher, F., Morgan, B. J. & Salanne, M. (2016) Sparse Cyclic Excitations Explain the Low Ionic Conductivity of Stoichiometric Li7La3Zr2O12. Phys. Rev. Lett. 116 135901.
Added by: Richard Baschera (2016-04-26 07:37:34) |
| Type de référence: Article DOI: 10.1103/PhysRevLett.116.135901 Numéro d'identification (ISBN etc.): 0031-9007 Clé BibTeX: Burbano2016 Voir tous les détails bibliographiques  |
Catégories: INTERNATIONAL, ST2E Mots-clés: 1st-principles, conductors, dynamics, garnet-type li7la3zr2o12, liquid, phase-transition, polarization, simulation, systems, transport Créateurs: Boucher, Burbano, Carlier, Morgan, Salanne Collection: Phys. Rev. Lett. |
Consultations : 1/573
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We have performed long time scale molecular dynamics simulations of the cubic and tetragonal phases of the solid lithium-ion electrolyte Li7La3Zr2O12 (LLZO), using a first-principles parametrized interatomic potential. Collective lithium transport was analyzed by identifying dynamical excitations: persistent ion displacements over distances comparable to the separation between lithium sites, and stringlike clusters of ions that undergo cooperative motion. We find that dynamical excitations in c-LLZO (cubic) are frequent, with participating lithium numbers following an exponential distribution, mirroring the dynamics of fragile glasses. In contrast, excitations in t-LLZO (tetragonal) are both temporally and spatially sparse, consisting preferentially of highly concerted lithium motion around closed loops. This qualitative difference is explained as a consequence of lithium ordering in t-LLZO and provides a mechanistic basis for the much lower ionic conductivity of t-LLZO compared to c-LLZO.
Added by: Richard Baschera |