What is "tricarbonate"

In organic chemistry, a tricarbonate is a compound containing the divalent [–O–(C=O)–O–(C=O)–O–(C=O)–O–] functional group, which consists of three carbonate groups in tandem, sharing two oxygen atoms. These compounds can be viewed as double esters of a hypothetical tricarbonic acid, HO–(C=O)–O–(C=O)–O–(C=O)–OH. An important example is di-tert-butyl tricarbonate (HC–)C–CO–C(–CH), a chemical reagent (colorless prisms that melt at 62–63 °C with decomposition, soluble in pentane).

The term "tricarbonate" is sometimes used for salts that contain three carbonate anions in their stoichiometric formula, such as cerium tricarbonate Ce(CO).