Crystal Structures of the Y3CuSiS7 and Y3CuSiSe7 Compounds.

Abstract The crystal structures of the compounds Y3CuSiS7 and Y3CuSiSe7 (La3CuSiS7 structure type, space group P63, Pearson symbol hP24) were determined by means of X-ray single crystal diffraction: a = 0.9854(1) nm, c = 0.5656(1) nm, R1 = 0.0267 (Y3CuSiS7); a = 1.0269(1) nm, c = 0.5954(1) nm, R1 = 0.0346 (Y3CuSiSe7). The packing of the Y-centered distorted trigonal prisms, Cu-centered triangles and Si-centered tetrahedra along the c direction in the structures of Y3CuSiS7 and Y3CuSiSe7 compounds exists.