Main group-transition metal cluster open compounds

Figure 3 Isomeric possibilities for structures for E Mx-n, n = (x — 1) — l,x = 4-6. Only the geometry of highest total vertex connectivity (usually denoted as closo but note the ambiguity for x = 4) and that of next highest (usually denoted as nido) are shown for economy of space. Likewise, only the binary E and M clusters are enumerated. Clearly, many more structures are possible if more open structures are allowed or more than one type of main group or transition metal element is used in the compound...

Metallacarboranes are cluster compounds in which the cluster vertices comprise one or more metal atoms (main group metal, transition metal or rare earth [lanthanide or actinide] metal), one or more (most often two) carbon atoms, and boron atoms, the last usually in the majority. The total number of cluster vertices may vary but the vast majority of metallacarboranes have between 6 and 14 vertices moreover, the cluster may be either open or closed. However, the single largest group of metallacarboranes has 12 vertices and is structurally based on the closed icosahedron, 1. 

After having received his PhD in 1985 at KU Leuven, Marc F. A. Hendrickx was the second researcher to join the theoretical chemistry group of this university as a permanent member of the academic staff. Since then, the main focus of his research activities has been on the study of properties of a wide variety of transition metal compounds. His recent research activity is mainly directed toward applying quantum chemical methods on small transition metal-containing clusters. Their frequently complicated open-shell electronic structures are studied in relation to their magnetic and spectroscopic properties. 

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