Multiple Ion Cores in Anthracene Anion Clusters

Spreading the charge: Anion clusters of anthracene, (An) n − , with n values of up to 6 were studied and found to contain a distinctly monomeric, dimeric, or trimeric ion core with a delocalized electronic charge (see figure). Coexistence of dimeric and trimeric ion cores was observed in (An) 4 − , but the ion core reverts to a monomeric one in (An) 5 − , with the completion of a solvation shell around the monomer anion.