The formation energy and stability
of radical anions in a series
of 12 phenyl- and 2-thienyl-ended linear, symmetric azomethines and
azines were investigated by cyclic voltammetry. Replacing 1,4-phenylene
with 2,5-thienylene cores and substitution with cyano or methyl moieties
have allowed the lowering of lowest unoccupied molecular orbital energy
levels even by 1 eV. Methyl capping stabilizes electron carriers (radical
anions) toward dimerization, and the mechanism of such radical anion
dimerization has been clarified by cyclic voltammetric kinetic analysis.
The results have been compared with optical parameters and supported
by density functional theory calculations.