AlO2

AlO2 is a chemical formula that can refer to more than one related species in aluminum oxide chemistry, depending on context. In common discussions, there is no widely isolated neutral compound with the formula AlO2 under ordinary conditions. More often, the notation appears in reference to the oxide fragment in larger clusters, or as a conceptual unit within oxoanions or transient species studied in specialized environments.

In anionic form, AlO2− would correspond to a simple oxoanion derived from aluminum in a high-oxidation-state oxide environment. Such a species is not a major, well-characterized aqueous ion in standard chemistry, and its stability tends to be limited to specific solid-state, molten, or highly basic settings where aluminum can balance charge with oxide ligands. As a result, AlO2− is not a common component of most aluminates encountered in ordinary solution chemistry.

In gas phase and materials research, AlO2 has appeared as a transient or a fragment in studies of aluminum-oxygen systems, such as combustion, flame chemistry, or cluster chemistry. In these contexts, it is typically discussed as a possible intermediate or theoretical construct rather than as a separately isolable, stable molecule. The exact electronic state, geometry, and spectroscopic signatures of AlO2 in such studies remain topics of ongoing investigation and have not led to a universally accepted, standalone species.

Related compounds include AlO (aluminum monoxide), a known diatomic radical, and Al2O3 (aluminum oxide) as the stable oxide in bulk materials. Aluminate chemistry more commonly features larger oxoanions such as [AlO4]− in alkaline systems.