Octahedral geometry osmium

The most common oxidation states and the corresponding electronic configurations of osmium ate +2 and + (t5 ), which ate usually octahedral. Stable oxidation states that have various coordination geometries include —2 and 0 to +8 (P] The single most important appHcation is OsO oxidation of olefins to diols. Enantioselective oxidations have also been demonstrated. 

Coordination about the osmium in 47 is best regarded as distorted trigonal bipyramidal with axial triphenylphosphine ligands. The distortion is toward a square pyramidal geometry with an apical nitrosyl ligand. Coordination about Os in the six-coordinate phenylcarbene complex is octahedral, as expected. 

The analysis has subsequently been extended to other Co(L)3 complexes [331] as well as M(bipy)32+ and M(phen)32+ complexes [332]. In the former study, L represents the unsaturated ligands acetylacentonate (acac), oxalate (ox), malonate (mal), and dithioxalate (diox). In the latter study, M represents the metals iron, ruthenium, and osmium. For the cobalt complexes, BP86/TZP computed spectra were in acceptable agreement with their experimental counterparts. The unsaturated ligands cause more complicated spectra due to the presence of both a and % orbitals, and therefore the analysis was somewhat more challenging. The distortions of the geometry away from an idealized octahedral metal environment resulted not... 

Ruthenium(III) and osmium(III) complexes are all octahedral and low-spin with 1 unpaired electron. Iron(III) complexes, on the other hand, may be high or low spin, and even though an octahedral stereochemistry is the most common, a number of other geometries are also found. In other respects, however there is a gradation down the triad, with Ru occupying an intermediate position between Fe and Os . For iron the oxidation state +3 is one of its two most common and for it there is an extensive, simple, cationic chemistry (though the aquo... 

Osmium forms numerous condensed carbonyl clusters because of its ability to readily form Os(CO)4 and Os(CO)3 units which can exhibit different geometries and bonding modes. However, higher-nuclearity osmium clusters with EMc2 (E = Ge, Sn) units usually have an open, planar arrangements of metal atoms. This is because EMe2 is isolobal with Os(CO)4, which adopts an octahedral coordination. ... 

The identity of this complex was subsequently confirmed by X-ray crystallography [127]. The geometry around the osmium ion is octahedral with transphosphine groups, cis-chloro ligands, a carbonyl ligand and the HNO moiety. Structural parameters of the latter (H-N=0.94A, N-0=1.193A and ZH-N-O =99°) compare favorably with those of 1.026 A, 1.211 A and 108.5° observed for... 

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