Preparation and crystal structures of new barium zirconium sulfides, Ba2ZrS4 and Ba3Zr2S7

New barium zirconium sulfides, Ba2ZrS4 and Ba3Zr2S7, have been prepared by the reaction of CS2 with mixture of BaCO3 and BaZrO3. The crystal structures of the compounds were refined on the powder X-ray diffraction data. The result showed that Ba2ZrS4 [tetragonal, I4/mmm, a = 4.7852(1) Å and c = 15.9641(3) Å] crystallizes in the K2NiF4 type structure, and Ba3Zr2S7 [orthorhombic, Cccm, a = 7.0697(2) Å, b = 25.4923(7) Å and c = 7.0269(2) Å] has a distorted variant of the X3Y2Z7 type structure which is closely related to the perovskite structure.