μ3-Oxido-tris­{dichlorido[1,3-bis­(1,3,5-trimethyl­phen­yl)imidazol-2-yl­idene]gold(III)} bis­(trifluoro­methane­sulfon­yl)imide–[bis­(trifluoro­methane­sulfon­yl)imide]­silver(I) (1/2)

The unusual trinuclear Au(III) oxide title complex, [Au(3)Cl(6)O(C(21)H(24)N(2))(3)](C(2)F(6)NO(4)S(2))·2[Ag(C(2)F(6)NO(4)S(2))], is the side product of the reaction of [1,3-bis-(1,3,5-trimethyl-phen-yl)imidazol-2-yl-idene]dichloridophenyl-gold(III) with silver bis-(trifluoro-methane-sulfon-yl)imide in the presence of traces of water. In contrast to corresponding Au(I) complexes, the core structure of the title compound is planar. Two silver(I) bis-(trifluoro-methane-sulfon-yl)imide units are loosely bound to the complex cation. Here the silver atoms, disordered over two positions in a 0.870 (2):0.130 (2) ratio, inter-act either with the lone pairs of three chlorine ligands or two chlorine ligands and one edge of the mesityl π-system. The crystal under investigation was a partial racemic twin.