Crystal structures of the Ln4−xIn5−yS13 (Ln=La, Ce, Pr and Nd; x=0.08–0.12, y=0.21–0.24), La3In1.67S7, Gd3InS6 and La4Ag2In4S13 compounds

The orthorhombic crystal structures of the series of Ln4−xIn5−yS13 (Ln=La, Ce, Pr and Nd; x=0.08–0.12, y=0.21–0.24) compounds were investigated by means of X-ray crystal diffraction. The crystals of La3In1.67S7 and Gd3InS6 were also obtained unexpectedly from the La–In–S and Gd–In–S systems and no respective Gd4−xIn5−yS13 was obtained. In the structures of the orthorhombic Ln4−xIn5−yS13 series and hexagonal La3In1.67S7 indium atoms occupy disordered positions in the octahedral and trigonal antiprismatic arrangement of the sulphur atoms. The crystal structure of the La4Ag2In4S13 is also given and discussed as an example of quaternary sulphide related to a ternary La–In sulphide.