Oxalate complexes, osmium

Ruthenium, iridium and osmium Baths based on the complex anion (NRu2Clg(H20)2) are best for ruthenium electrodeposition. Being strongly acid, however, they attack the Ni-Fe or Co-Fe-V alloys used in reed switches. Reacting the complex with oxalic acid gives a solution from which ruthenium can be deposited at neutral pH. To maintain stability, it is necessary to operate the bath with an ion-selective membrane between the electrodes . 

Os forms many complexes with nitnte. oxalate, carbon monoxide, amines, and thio ureas. The latter arc important analytically Osmium forms the interesting aromatic sandwich" compound, osmocene. A metallocene is described under Ruthenium. See also Chemical Elements and Platinum and Platinum Group. 

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... 

The product of the corresponding reaction with acetaldehyde is oxalate, the rate-determining process in this instance being considered to derive from the reaction of an osmium(vm)-enolate complex in a two-electron step, the resulting Os being re-oxidized to its original oxidation state by reaction with Fe(CN)6 "-... 

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