RB[RE3BR10] - THE 1ST TERNARY RHENIUM(III) HALIDE WITH A CHAIN STRUCTURE

Rb[Re3Br10] crystallizes one evaporation of a hydrobromic acid solution of rhenium tribromide and rubidium bromide as dark red-brown single crystals. The crystal structure (monoclinic; C2/m; a = 1469.09(10); b = 1085.75(8); c = 1019.15(8) pm; beta = 91.81(1)-degrees; V(m) = 245.1(2) cm3mol-1; Z = 4) is built up of chains along [010] of [Re3Br12] units that are connected via two edges. The anionic chains are held together by rubidium ions. Each cation is surrounded by eight bromide ions at distances between 332 and 368 pm with four additional bromide ions at 401 to 427 pm. This is the first example of a ternary rhenium halide with a chain structure. Only salts with isolated cluster anions [Re3X12-y(H2O)y](3-y)- (X = Cl, Br; y = 0-3) have been known so far.