Structure of tin hafnium sulfide and lead hafnium sulfide

SnHfS3, Mr=393.36, orthorhombic, Pnma, a=9.139(1), b=3.694(1), c=13.875(4) A, V=468.4(2) A3, Z=4, Dx=5.578 g cm-3, λ(Mo K anti α)=0.71073 A, μ=284.1 cm-1, F(000)=680, T=298 K, RF=0.036 for 1301 observed reflections with I≥2.5σ(I). PbHfS3, Mr=481.88, orthorhombic, Pnma, a=8.988(2), b=3.739(1), c=13.924(2) A, V=467.9(2) A3, Z=4, Dx=6.840 g cm-3, λ(Mo K anti α)=0.71073 A, μ=593.0 cm-1, F(000)=808, T=298 K, RF=0.036 for 1343 observed reflections with I≥2.5σ(I). The compounds are isostructural with PbZrS3 with modified NH4CdCl3 structure. There are columns running along the b axis of double edgesharing octahedra (Hf2S6)∞; these columns are linked by Sn or Pb with coordinations typical for Sn2+ and Pb2+ with lone-pair s2 electrons. (orig.)