Metallo-dithiolenes

Let us now pass to metallo-dithiolene complexes, which constitute a relatively old class of compounds,68 which are a matter of great renewed interest in the field of superconduction just because of their extended redox propensity.69... 

The Electronic Structure and Spectroscopy of Metallo-Dithiolene Complexes... 

The numerous properties of metallo-dithiolene complexes are a direct consequence of the fantastic redox interplay between the redox-active metal and the dithiolene ligand. A considerable amount of experimental evidence over the last 40 years has pointed to the fact that dithiolenes are highly noninnocent ligands (20, 86, 110, 113, 280-282). That is, they may be viewed in a valence bond description as existing somewhere between the extremes of neutral (dithione/dithiete) and dianionic (dithiolate) forms (Fig. 1). This variable formal... 

The most detailed spectroscopic and electronic structure studies of metallo-mono(dithiolenes) have focused on the nature of ligand-to-ligand charge transfer (LLCT) excitations in [M(diimine)(dithiolene)] complexes (112, 250-257, 262, 264, 295-301) and in monooxo molybdenum dithiolenes (19, 20, 22, 23) as models for pyranopterin molybdenum enzymes such as sulfite oxidase (SO). Since metallo-mono(dithiolenes) generally possess little or no symmetry, detailed spectrosopic and electronic structure studies of this class of metallo-dithiolenes have only recently begun to appear. The analysis of the spectroscopic data has been aided by the fact that the dithiolene-to-metal charge... 

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