SEARCH Articles Figures Tables Charge-localized and -delocalized Valence Tautomeric Forms of Cyclic Oxocarbon Dianions Croconate oxocarbons Cyclic Oxocarbon Acids Deltate oxocarbons Oxocarbon anions Oxocarbon dianions Oxocarbon ligands dianionic Oxocarbons Oxocarbons Oxocarbons and coordination chemistry Pseudo-oxocarbons Squarate oxocarbons Trapping Cyclic Oxocarbon Dianions in the Crystalline State