Direct observation of conformational change of adipate dianions encapsulated in water clusters

Two novel hydrated adipate dianions including (adip)aaa·(H2O)16 and (adip)gag·(H2O)20 (adip = dianion of adipic acid, aaa = anti–anti–anti and gag = gauche–anti–gauche) were observed in two silver-based cationic hosts. They not only reveal the precise arrangement of water clusters around the carboxylate groups and aliphatic chains of adipate dianions, but show the conformational change of adipate dianions in water clusters, for the first time.