The crystal and molecular structure of ammonium µ-nitrido-bis[aquotetrachlororuthenate(IV)]

Abstract

The crystal and molecular structure of ammonium µ-nitrido-bis[aquotetrachlororuthenate(IV)], (NH₄)₃[Ru₂NCl₈–(H₂O)₂], has been determined from X-ray diffractometer data (MoK-α radiation, R= 0·071 for 1054 reflections). Unit cell dimensions are a= 15·910 Å, b= 7·642 Å, c= 8·399 Å, γ= 121·09° with two molecules per unit cell, in space group B2/m. The compound contains ammonium cations and complex [Ru₂NCl₈(H₂O)₂]^3– anions. The co-ordination about the two metal atoms in the anion is approximately octahedral. The two octahedra are joined by a bridging nitrogen atom, which is at a centre of symmetry. The Ru–N distances are very short, 1·725 Å, indicating multiple bonding. The two independent Ru–Cl distances are 2·370 Å and 2·391 Å. The Ru–O(water) distance of 2·20 Å is long by comparison with previously reported values.