UV/Vis/NIR spectral properties of triarylamines and their corresponding radical cations

Abstract: The one-electron oxidation potential of 10 triarylamines 1–10 with all permutations of chloro-, methoxy- and methyl-substituents in the three para-positions were determined by cyclic voltammetry. The half wave potential E 1/2(I) of the first oxidation wave correlates linearly with the number of chloro- and methoxy-substituents. A high long-term stability of the first oxidation wave for all triarylamines was observed by multi-cycle thin-layer measurements. AM1-CISD derived values of the absorption energies are in good agreement with the experiments but differ strongly for the oscillator strengths as well as for neutral compounds 1–10 and their corresponding mono radical cations. The small solvent dependence of the experimental UV/Vis spectra in CH2Cl2 and MeCN reflects a minor charge transfer (CT) character of the electronic transitions of neutral and cationic compounds. [Copyright &y& Elsevier]