Yb₃O(OH)₆Cl·2H₂O: An Anion-Exchangeable Hydroxide with a Cationic Inorganic Framework Structure

The first anion-exchangeable framework hydroxide, Yb₃O(OH)₆Cl·2H₂O, has been synthesized hydrothermally. This material has a three-dimensional cationic ytterbium oxyhydroxide framework with one-dimensional channels running through the structure in which the chloride anions and water molecules are located. The framework is thermally stable below 200 °C and can be reversibly dehydrated and rehydrated with no loss of crystallinity. Additionally, it is able to undergo anion-exchange reactions with small ions such as carbonate, oxalate, and succinate with retention of the framework structure.