The structure of IrO2 Cl(CO)(P(C6 H5)3)2, which is the oxygen adduct of the synthetic molecular oxygen carrier IrCl(CO)(P(C6 H5)3)2, has been determined from three-dimensional X-ray data collected from a single crystal. The material crystallizes in space group C2 -Pl of the triclinic system with two molecules in a cell of dimensions a = 19.02, b = 9.83, c = 9.93 Å. α = 94.0, β = 64.9, γ = 93.2°; V = 1676 Å.3. The crystal structure consists of the packing of discrete, monomeric molecules. The molecular structure surmised by Vaska from spectroscopic data has been confirmed, and, in addition, details of the attachment of molecular oxygen to iridium have been obtained. The iridium may be described as either five-or six-coordinated: the iridium, the two oxygen atoms, the carbonyl group, and the chlorine atom lie in the basal plane, with phosphorus atoms above and below this plane. The two oxygen atoms are equidistant from the iridium atom, with an average Ir-O distance of 2.07 Å. The O-O bond length of 1.30 ± 0.03 Å. is intermediate between those characteristic of O2 (1.21 Å.) and O2 -2 (1.49 Å.) and corresponds closely to O2 (1.28 Å.).
ASJC Scopus subject areas
- Colloid and Surface Chemistry