Osmiamate ion

The osmiamate ion, Os03N, is isoelectronic with Os04. The yellow potassium salt is the most convenient one to prepare other, less soluble, salts, can be made by metathesis ... 

There are now a substantial number of nitrido complexes of osmium(VI) and osmium(IV) as well as the osmiamate ion [OsVII 03N]. In addition to the ammine and ethylenediamine complexes, much recent work has been carried out on the bipy, phen and terpy complexes, often in connection with research into the photodissociation of water. The nitrosyl chemistry of the element, though seemingly not as extensive as that of ruthenium, has received much attention, and there has been considerable work on the phosphine, arsine and stibine complexes. 

The osmiamate ion, [Os03N] , was the first example to be prepared of complex ions in which nitrogen is bound to a transition metal by a multiple bond. 

Although the osmiamate ion is stable in alkaline solution, it is readily reduced by HC1 or HBr, and from the resulting red solutions red crystals of salts such as K2[OsvlNCl5] can be obtained.43 This chloronitrido anion is... 

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