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Title: Impacts of vacancy-induced polarization and distortion on diffusion in solid electrolyte Li 3 OCl
Lithium-rich oxychloride antiperovskites are promising solid electrolytes for enabling next-generation batteries. Here, we report a comprehensive study varying Li + concentrations in Li 3 OCl using ab initio molecular dynamics simulations. The simulations accurately capture the complex interactions between Li + vacancies ( V Li ′ ), the dominant mobile species in Li 3 OCl . The V Li ′ polarize and distort the host lattice, inducing additional non-vacancy-mediated diffusion mechanisms and correlated diffusion events that reduce the activation energy barrier at concentrations as low as 1.5% V Li ′ . Our analyses of discretized diffusion events in both space and time illustrate the critical interplay between correlated dynamics, polarization and local distortion in promoting ionic conductivity in Li 3 OCl . This article is part of the Theo Murphy meeting issue ‘Understanding fast-ion conduction in solid electrolytes’.  more » « less
Award ID(s):
1710630
PAR ID:
10302694
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Date Published:
Journal Name:
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
Volume:
379
Issue:
2211
ISSN:
1364-503X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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