Inorganic Chemistry, Vol.33, No.9, 1733-1734, 1994
Synthesis of New Low-Dimensional Quaternary Compounds, Kcu2Ass3 and Kcu4Ass4, in Supercritical Amine Solvent - Alkali-Metal Derivatives of Sulfosalts
The reaction of KAsS2, copper powder, and elemental sulfur in supercritical ethylenediamine (300-350-degrees-C and 3500 psi) leads to formation or two new quaternary solids having the formulas KCu2AsS3 and KCu4AsS4. Both products are orange crystalline solids having complex low-dimensional structures of Cu(I) linked by AsS33- groups, forming layers (for KCu2AsS3) or channels (for KCu4-AsS4). The KCu4AsS4 compound also contains lone sulfide ions, which help to cross-link layers. Both solids can be considered alkali metal derivatives of sulfosalts.