New compounds of the Li2MSn3S8 type
The substitution of Cu/Ag by lithium in complex thiospinels with the general formula AI2BIICIV3XVI8 was achieved by ball milling and a subsequent annealing step in an atmosphere of H2S. Four hitherto unknown compounds Li2MSn3S8 with M = Mg, Mn, Fe, Ni were obtained without side phases and have been structurally investigated. From X-ray powder diffraction experiments, space group Fd¯3m and a spinel-type structure are suggested. In these so-called normal spinels, lithium occupies one eighth of the tetrahedral voids (Wyckoff position 8a) of the cubic closest packing of the sulfide ions whereas M and Sn can be found on one half of the octahedral voids (Wyckoff position 16d).
Published in: Zeitschrift für Naturforschung B, 10.1515/znb-2020-0050, De Gruyter