Preparation of New Ba4M3S10 Phases (M = Zr, Hf) and Single Crystal Structure Determination of Ba4Zr3S10

Two new Ruddlesden-Popper Ban+1Mn S3n+1 compounds where M = Zr, Hf and n = 3 have been prepared in good yield from BaS, M, and S in a BaCl2 flux at 1050°C. The structures comprise triple layer perovskite slabs separated by double BaS layers. The single crystal structure of Ba4Zr3S10 revealed Zr-S distances of 2.493(3) Å (average) with one long Zr-S contact of 2.562(5) Å for the distal bond of the ZrS6 octahedron at the perovskite/double BaS interface. The Ba-S contacts average 3.52(1) Åinside the perovskite blocks and range between 3.084(5) and 3.552(1) Å in the double BaS layers. Crystal data for Ba4Zr3S10 (25°C) are a 7.0314(5) Å, b = 7.0552(7) Å, c = 35.544(7) Å, Z = 4, Dcalc = 4.038 g/cm3, orthorhombic, space group Fmmm, R(F) = 0.038, Rw (F) = 0.058. Single crystals of Ba4Hf3S10 were indexed on an orthorhombic cell with a = 6.989(3) Å, b = 7.022(2) Å, and c = 35.428(8) Å but the structure was not refined due to poor quality data.