Trigonal bipyramid trinuclear complexes

Last but not least, mention should be made of the use of redox active organometallic clusters for the formation of CT complex. An early example was reported by Eisenberg, Miller and co-workers who exploited the trinuclear niobium cluster [Nb3(/i-Cl)6(>7 -C6Me6)3] and prepared the [TCNQ] salt, upon oxidation to the dicationic form. This material was found to be paramagnetic and to display a relatively modest conductivity (urt = 0.001 Scm , semiconductor) [75]. Finally, the pentanuclear trigonal bipyramidal vanadium cluster [(MeCp)5V5(/r -S)6] was shown to undergo CT complex formation with TCNQ affording [(MeCp)5V5(/i -S)6] [(TCNQ)2] [76]. This material, which was structurally characterized, is an n-type semiconductor with a band gap of 0.25 eV. 

Triclinic crystal system, 75, 78 Trigonal bipyramidal (TBP) structure, 480-483 Trigonal crystal system, 75, 78 Trigonal hybrid, 150-153 Trigonal prism, 489-491 Trimethylborane, 205 Trinegative ions, 332-333 Trinuclear clusters, 813-815 Tropylium complexes, 683-684 Tutankhamen, 458 Twist angles, 490... 

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