Crystallographic analysis of sulfides related to bismuthinite Bi2S3

Resumo

The crystallographic analysis of Bi₂S₃, CuPbBi₅S₉, CuPbBi₃S₆, and CuPbBiS₃ compounds, representing a series with a successive replacement of a part of Bi atoms by Pb+Cu, shows that they are characterized by a stable combination of a pseudotetragonal cation framework with a pseudohexagonal anion one, which is common for all structures, within orthorhombic unit cells with n sizes of 11.2 Å, 4 Å, and 11.5 Å. The Bi₂S₃ cation framework is retained for the heavy Bi+Pb, and additional light Cu fill the available vacant sites without changing its geometry but varying the crystallographic symmetry within the orthorhombic crystal symmetry and unit cells of n standard blocks (11.2×4×11.5 ų).