Lithium insertion into In2S3 studied by perturbed γ-γ angular correlation
Résumé
LixIn2S3 was electrochemically prepared with different small amounts x of lithium (0≤x≤0.13) in order to maintain the initial crystallographic structure of the thiospinel In2S 3. About 1012 radioactive 111In ions have been implanted into these samples at 400keV to perform PAC experiments in the temperature range from 10 to 773K. The results are compared to previous experiments with undoped In2S3 samples. According to the structure of In2S3 in the β-phase, which belongs to the I41/amd space group having a unit cell with 32 In and 48 S atoms and the cell parameters α=7.61Å and c=32.28Å, three different electric field gradients were observed. Within two different temperature ranges dynamical EFGs occur, which are clearly influenced by the insertion of Lithium. The strong dependence of one EFG on the Li concentration x can be correlated to the effective charge of the In ions. This correlation is discussed with respect to XRD analyses of the LixIn2S3 samples and to XANES measurements on a similar sample. © 2003 Published by Elsevier Inc.