Cluster Complexes

A compound having a triangular or bigger closed polyhedron of metal atoms is the best classification for a cluster compound. Therefore, compounds containing electrons 66 (chain compound), 68, 70, and 72 (cubane-like or cage compound) are not considered clusters; yet, as previously indicated, these compounds are included in this study due to their inherent importance. The chemistry of the transition metals is given a dimension of nearly limitless variation by metal cluster complexes. Transition metal NMR will make it much easier to examine the chemistry that exists at the boundary between complexes of single metal atoms and those of tiny metal particles. From Rh4(CO)12 and Rh6(CO)16, rhodium forms a number of clearly defined clusters that have served as the foundation for the majority of the cluster chemistry of rhodium so far. Heaton and coworkers have published more than 30 publications presenting 103Rh data, by far the most of any group to contribute to the study of tiny rhodium-containing clusters by 103Rh NMR.26,27,136,142-171.