The structure of trimethylphenylammonium nonachlorodirhodate(III) and a survey of metal-metal interactions in confacial bioctahedra

摘要: Abstract The structure of the Rh2Cl93− ion has been determined by X-ray crystallographic study [(CH3)3C6H5N]3 Rh2Cl9. crystals are orthorhombic with dimensions a = 32.487(14), b 9.274(5), and c 36.451 (14), observed density (1.70 g/ml) requires Z 12 (which gives ϱ 1.69 g/ml). Systematic absences were consistent space groups Pmma, Pma2 Pmc21; latter (in form P21ma) was selected on basis Patterson function. Difficulties caused disorder cation orientations. In end, refined in group Pnma, axis 1 3 length P21ma. reflections l ≠ 3n P21ma thus all omitted; these almost entirely very weak ones, omitting them virtually necessity order to reduce computing tractable proportions. For final refinement asymmetric unit consisted one ion, ordered cation, atoms which at full weight, partially disordered single orientation 2 weight third nitrogen methyl carbon while each two ring orientations 6 weight. virtual D3h symmetry shows symmetry-preserving distortions from ideal bioctahedron indicative RhRh repulsion. distance is 3.121(5) A RhClRh angles have an average value 81.3 (3)°. When as well those 13 other M2X9 bioctahedra analyzed terms various parameters reflect magnitude sense (i.e., attractive or repulsive) MM interactions, systematic correlations electronic structures position periodic table found.