Nitride-bridged cluster

For nitrido clusters, open butterfly structures with a RU4 core are observed in (38) and the precursor molecules (35) or (37), where one nitride or isocyanate ligand bridges the open wings of the butterfly. RusN cores, exemplified by [RusN(CO)i4] (41), are of a similar square pyramidal arrangement as RusC clusters. The nitrido atom in the former is displaced out of the basal plane by as much as 0.21 A (i.e. about twice as much as the carbon atom in (30)) making the transition to a distorted octahedron. The decanuclear complex... 

The presence of one or several nitrides is effective at modifying the metal cluster structure. Face bridging naked nitrides are not known but a nitrogen atom with a T-shaped coordination has been found in [Mo3(N )(0)(C0)4(C5H5)3]. Semi-exposed nitrides have been found in the species with four or five metal atoms they are invariably encapsulated into clusters of higher nuclearity. All the tetranuclear... 

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