Cation-deficient thiospinel; Chemical synthesis; Crystal structure and symmetry
Starting from pure metals and sulphur in evacuated silica tubes single crystals of Cu7.38(11)Mn4Sn12S32 and Cu7.07(6)Ni4Sn12S32 have been obtained by quenching from 680 °C. These crystallize in the Fdm space group and have a=10.4145 (7) and 10.305 (1) Å, respectively. The atomic parameters, occupancies and anisotropic thermal parameters were refined to give a final R-value of 0.0209 and 0.0181 for Cu7.38Mn4Sn12S32 and Cu7.07Ni4Sn12S32, respectively. A significant amount of cation deficiency exists at 8a site of the quaternary spinel structure.