The complexes Ni(dmeds)(dmit), Ni(dmedt)(dmit), Ni(dpedt)(dsit), Ni(dpedt)(dmit), and Ni(dcdt)(dmit) (where dmeds is dimethylethylenediselenolate, dmedt is dimethylethylenedithiolate, dpedt is diphenylethylenedithiolate, dcdt is 1,2-bis-decylsulfanyl-ethene-1,2-dithiolate, dmit is 1,3-dithiol-2-thione-4,5-dithiolate, and dsit is 1,3-dithiol-2-thione-4,5-diselenolate) were prepared and characterized. The new complexes exhibit semiconducting behavior, with band gap values around 0.8 eV.
The air-stable unsymmetrical complexes Ni(dt)(dmit), Ni(dt)(dmio), Ni(tmdt)(dmit), Ni(tmdt)(dmio), Ni(etdt)(dmit), Ni(etdt)(dmio), Ni(ptdt)(dmit), and Ni(ptdt)(dmio) (where dmit is 1,3-dithiol-2-thione-4,5-dithiolate, dmio is 1,3-dithiol-2-one-4,5-dithiolate, dt is tetrathiafulvalendithiolate, tmdt is trimethylenetetrathiafulvalenedithiolate, etdt is ethylenedithiotetrathiafulvalenedithiolate, and ptdt is propylenedithiotetrathiafulvalenedithiolate) were prepared and characterized analytically, electrochemically and spectroscopically. In the solid state, the compounds exhibit optical absorption edges between 0.70 and 0.82 eV. Their LUMO and HOMO levels occur at ca. 4.5 and 5.3 eV, respectively.