@article{oai:repo.qst.go.jp:00080579,
author = {Morita, Kenji and Hoshino, Tsuyoshi and Kenji, Morita and Tsuyoshi, Hoshino},
journal = {Solid State Ionics},
month = {Sep},
note = {We investigate isotope effects of lithium-ion diffusion in Lithium-ion conductors using ab initio computational methods in light of recently proposed novel lithium isotope separation technology based on ionic conductors. Using ab initio molecular dynamics simulations, we compute the diffusion coefficients D6(7) of 6Li+ (7Li+) in tetragonal Li7La3Zr2O12 and Li10GeP2S12 as a slow Li+-ion conductor and a fast Li+-ion conductor, respectively. We note that careful uncertainty estimations in the molecular dynamics simulations would be necessary to extract many-body effects on the diffusion coefficient ratio D6/D7 beyond the canonical value given by the transition-state theory. Numerical results for Li10GeP2S12 indicate that the isotope effect depends on the migration path. Specifically, the faster diffusion path along the c−axis exhibits a stronger isotope effect that is also temperature dependent, whereas the diffusion on the ab−plane shows a relatively weaker and temperature-independent effect. We introduce the probability distribution of the ionic displacement to reveal distinct differences in the ion-diffusion mechanism.},
title = {Ab initio molecular dynamics study of isotope effects in lithium-ion conductors},
volume = {355},
year = {2020}
}