Dithiolenes charge transfer salts

Although most compounds prepared from neutral parent molecules are neutral DA complexes, in some cases an ionic charge-transfer salt results. In addition, there are compounds prepared from D+p and A-q subunits which have been found to be ionic. Many of the ionic crystals involve A q units that are variants on metal bis-ethylene-1,2-dithiolenes, namely [M(tfd)2] and [M(mnt)2]-2. A variety of planar organic cations have been used to prepare such solids TTF+ M5), POZ+ 56 57), PTZ+ 56 57), and NMP+ 59). A... 

All crystals in this class are either insulators or semiconductors, and with a single exception (discussed in Sect. 3.3), they are ionic charge-transfer salts. The cations are generally either planar aromatics, such as TMPD+ and TTT+ (Sect. 3.2) or onium counter ions, such as Et4N+ and MePh3P+ (Sect. 3.3), although some cationic metal complexes are also known. For a majority of the systems, the anionic components are bis-1,2-dithiolene metal complexes, which have been studied and reviewed extensively81-84. ... 

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