LAPBCUS3 - CU(I) INSERTION INTO THE ALPHA-LA2S3 FRAMEWORK

The compound LaPbCuS3, lanthanum lead copper sulfide, has been prepared and characterized from single crystal X-ray data. LaPbCuS3 crystallizes in space group D162h-Pnma of the orthorhombic system, a = 8.091(3), b = 4.093(1), and c = 15.996(5) Å, V = 529.7 Å3 (T = 293 K), Z = 4, Mr = 505.84, Dx = 6.341 g/cm3, λ(MoKα1) = 0.7093 Å, μ = 448.8 cm-1, and R(Fo) = 0.030 and Rw(Fo) = 0.042 for 732 unique data with F2o > 3σ(F2o). The structure, which is related to that of α-La2S3, has 7-coordinate La and Pb atoms disordered unequally over two sites, with MS bond lengths in the range from 2.864(3) to 3.168(3) Å. The Cu atoms are in tetrahedral sites that form corner-sharing chains along the b direction, with CuS distances ranging from 2.336(4) to 2.385(4) Å. © 1992.