GeO32

GeO32, commonly written GeO3^2−, denotes the germanate(IV) oxoanionic species composed of one germanium atom bonded to three oxide groups and bearing an overall 2− charge. It is the conjugate base of germanic acid (H4GeO4) and is encountered in basic aqueous solutions as well as in the anionic units of various germanate salts.

In solution, the GeO3^2− ion is influenced by pH and concentration. Under strongly basic conditions it tends to be the predominant species, while closer to neutral pH it can form hydroxo- and polymeric germanate species. The GeO3^2− unit can also participate in condensation reactions to give higher-order germanate frameworks.

Preparation and occurrence: GeO2 reacts with alkali hydroxides to form germanates, for example GeO2 + 2 NaOH → Na2GeO3 + H2O. Salts such as Na2GeO3 and K2GeO3 are common examples, typically isolable as solids or stabilizable in solution. In solids, germanates often feature GeO3^2− units linked into networks or clusters.

Properties and reactivity: GeO3^2− can act as a ligand toward metal ions, forming coordination compounds and salts. It also participates in the formation of polymeric oxide networks and various higher-order germanate species in solution or solid state.

Applications: Germanate materials, including those derived from GeO3^2−, are used as precursors for germanium-containing glasses, ceramics, and related optical or electronic materials. The GeO3^2− unit thus plays a role in both fundamental oxoanion chemistry and materials synthesis.

See also: Germanate, GeO2, H4GeO4, Na2GeO3.