The crystal structure of potassium nitridopentachloroosmate(VI), K2OsNCl5, has been determined from three-dimensional X-ray data collected by counter methods and has been refined by least-squares techniques to a final R factor, based on F, of 3.3% for the 687 reflections above background. The material crystallizes in space group D2h 16-Pnma of the orthorhombic system in a cell with dimensions a = 13.27 (2) Å, b = 9.85 (1) Å, and c = 6.84 (1) Å. The density of 3.45 g/cm3 calculated for four formula units in the unit cell agrees with the observed density of 3.4 ± 0.1 g/cm3. The OsNCL5 2- ion is required crystallographically to possess m symmetry. The coordination about the Os atom is distorted octahedral. The Cl atoms cis to the nitrido ligand are bent away from the N atom. The Os-N distance, is 1.614 (13) Å. The three independent Os-Cl distances cis to the N atom do not differ significantly from one another and average 2.362 (2) Å, but the Os-Cl distance trans to the N atom is considerably longer at 2.605 (4) Å. This contradicts the results from a previously reported structure of K2OsNCl5 in which the trans Os-Cl distance was reported to be much shorter than the cis distances. The results on a number of compounds with metal-nitrogen multiple bonding are intercompared and trends are rationalized in terms of nonbonded interactions.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry