Thorium Group 16 compounds and complexes

Zachariasen [1949ZAC], [1949ZAC3] unambiguously identified four phases in the range S/Th = 0.8??????2.0 and elucidated their structures. From powder data, ThS(cr) is reported as cubic (NaCl type, Fm3m ), with a = (5.682??????0.002) Å and isomorphous with CeS and US, while ThS2(cr) is orthorhombic (PbCl2 type, Pnmb– 16 2h D ), with a??=??(4.267??????0.002), b = (7.264??????0.003), and c = (8.617??????0.003) Å. Using single crystal data, Zachariasen also reported Th2S3(cr) as orthorhombic (Sb2S3 type, Pbnm) with a??=??(10.99??????0.05), b = (10.85??????0.05), and c = (3.96??????0.03) Å, isomorphous with U2S3, and Th7S12(cr) hexagonal (P63/m), with a = (11.063??????0.001) and c = (3.991??????0.001) Å. It was also noted, at the time, that the homogeneity range for that phase extends from S/Th??= 1.71 to 1.76. 