Polynuclear compounds bridging ligands

Figure 2 Carbonato-bridged polynuclear compounds of varying nuclearity with different terminal ligands.

Locants for bridging ligands are cited in the same manner as in dinuclear compounds. Central atom locants will at times be necessary for monoatomic bridges in more complicated polynuclear compounds. For these compounds the locants are cited on the line before the ligand indicator k and are separated by a colon, e.g. tri- i-chloro-l 2KC/,l 3icC/,2 3KC/-. For examples see Table 20. 

In the case of the sulfate anion SO, complexes are described in which the ligand performs a terminal (104) or chelating (105) function in mononuclear compounds, but the same ligand behaves as a bridge ligand system (106) in di- and polynuclear structures [(3,13,128-131] ... 

Formation of polynuclear compounds with chalcogen atoms as bridging ligands between metal atoms is a characteristic feature of chalcogen metal carbonyl complexes. Such polynuclear complexes, in which often an additional metal-metal bond is assumed so as to account for the diamagnetism, have become known in increasing numbers because of the work of various research groups, and it is neither possible nor is it within the scope of this article to review this subject here. Only a few of our own results will be mentioned herein. 

The complexes with pincers, like Pt(dippy)L, can be used as starting materials for polynuclear compounds, if L is a bridging ligand ... 

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