Multistep π dimerization of tetrakis(n-decyl)heptathienoaceneradical cations: a combined experimental and theoretical study (original) (raw)

Radical cations of a heptathienoacene a,b-substituted with four n-decyl side groups (D4T7C + ) form exceptionally stable p-dimer dications already at ambient temperature (Chem. Comm. 2011, 47, 12622). This extraordinary p-dimerization process is investigated here with a focus on the ultimate [D4T7C + ] 2 p-dimer dication and yet-unreported transitory species formed during and after the oxidation. To this end, we use a joint experimental and theoretical approach that combines cyclic voltammetry, in situ spectrochemistry and spectroelectrochemistry, EPR spectroscopy, and DFT calculations. The impact of temperature, thienoacene concentration, and the nature and concentration of counteranions on the p-dimerization process is also investigated in detail.