Undecanuclear Rh-containing clusters

Controlled cluster growth has been shown in Eq. (8) and in Fig. 19. Related to the structures in Fig. 19 are those of [Rhn(CO)23] and [Pt2Rh9(CO)22] ° (Fig-20) in both of these the metal framework consists of three octahedra which each share a pair of adjacent triangular faces. The Rhu cluster occurs in two isomeric forms, which arise from different carbonyl site occupancies as a result of different crystal packings (Fig. 20b and c) both structures are related to that of the Rh9Pt2 cluster (Fig. 20d). 

Because of the similar energies for different CO-site occupancies (Fig. 20b and c), it is not surprising that both of these isomers have identical NMR spectra in solu- 

An unusual mixed metal nitride [RhioPtN(CO)2i] has been structurally characterized but no NMR data have been reported the metal geometry is unusual and the nitride occupies an unusual cavity in which it is connected to five metal atoms (one Pt and four Rhs). 

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