Präparative und röntgenographische Untersuchungen über Cäsium-Silber-Gold(III)-Chlorid

Abstract

Cesium silver gold(III) chloride has been prepared from hydrochloric acid solutions. The composition of the preparations is variable and depends on the ratio [Au(III)]/[Ag(I)] in solution. It corresponds to the formula Cs2Ag1-xAu1+x/3Cl6. In the range 0 ≤ x ≤ 0,64 six crystallographically different phases have been observed. Above x = 0,42 a cubic phase is obtained. The stoichiometric compound Cs2AgAuCl6 is obtained only from solutions with [Au(III)]/[Ag(I)] < 1. Reports in the literature which claim the stoichiometric compound Cs2AgAuCl6 to exist in a cubic and in a tetragonal form cannot be confirmed. Cs2AgAuCl6 crystallizes orthorhombically with the lattice constants a = 15,21 Å, b = 15,16 Å and c = 10,32 Å (Z = 8).