P. Mayorga Burrezo, N-T. Koji, K. Nakabayashi, S. Ohkoshi, E.M. Calzado, P.G. Boj, M. Díaz García, C. Franco, C. Rovira, J. Veciana, M. Moos, C. Lambert, J.T. López Navarrete, H. Tsuji, E. Nakamura, J. Casado.
Angew. Chem. Int. Ed. 2017, 56, 2898 –2902

Carbon-bridged bis(aminoaryl) oligo(para-phenylenevinylene)s have been prepared and their optical, electrochemical, and structural properties analyzed. Their radical cations are class III and class II mixed-valence systems, depending on the molecular size, and they show electronic couplings which are among the largest for the self- exchange reaction of purely organic molecules. In their dication states, the antiferromagnetic coupling is progressively tuned with size from quinoidal closed-shell to open-shell biradicals. The data prove that the electronic coupling in the radical cations and the singlet–triplet gap in the dications show similar small attenuation factors, thus allowing charge/spin transfer over rather large distances.

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