E. Grigiotti,a F. Laschi,a P. Zanello,a,*M. Arca,b C. Denotti, b F.A. Devillanovab
a Dipartimento di Chimica, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy.
b Dipartimento di Chimica Inorganica ed Analitica, Università degli Studi di Cagliari, S.S. 554 bivio per Sestu, 09042 Monserrato, Cagliari, Italy
Received 30 September 2003
Abstract
]]> The electrochemical properties of a series of [M(R,R’timdt)2] dithiolenes (M = Ni, Pd, Pt; R,R’timdt = monoanion of disubstituted imidazolidine-2,4,5-trithione) have been studied by cyclic voltammetry, controlled potential coulometry, and EPR spectroscopy. All the compounds undergo two separate one-electron reductions and one two-electron oxidation, which proceed through a single step in the case of nickel complexes, and through two separate steps in the case of palladium and platinum complexes. Inductive effects played by the R and R’ substituents influence the formal electrode potentials of the electron transfer processes. EPR spectroscopy has proved that the unpaired electron in monoanions [M(R,R’timdt)2]- is located on a SOMO, which, even if mainly ligand centred, is significantly contributed by the metal.
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*Corresponding author. E-mail address: zanello@unisi.it
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