Li4SnS4: Simulations of Its Structure and Electrolyte Properties

First principles simulations show that the ground state crystal structure of Li4SnS4 is isomorphous to Li4GeS4, in agreement with experiment, and having interstitial sites in void channels along the c axis. The simulations also show that a slightly meta-stable structure (Li4SnS4*) is formed by moving Li ions from their central sites to the interstitial positions, consistent with X-ray patterns resulting from relatively low temperature synthesis methods. The simulations suggest that the Li4SnS4* material has favorable ion conducting properties.