Ru2O3

Ru2O3, also called ruthenium(III) oxide, is a binary oxide of ruthenium with the formula Ru2O3. It contains ruthenium in the +3 oxidation state and is one of several ruthenium oxides. Compared with RuO2, Ru2O3 is less common and less well characterized; its existence is reported in solid-state and phase-diagram studies and under certain high-temperature or controlled oxygen conditions.

Formation and structure: Ru2O3 can be prepared in the laboratory by solid-state reaction of ruthenium precursors under specific oxygen partial pressures and temperatures. The crystal structure is not universally agreed and appears to depend on synthesis route and stoichiometry; proposed motifs range from corundum-like to other densely packed oxide structures, often with defects or non-stoichiometric variations. Diffraction data can be ambiguous, and sample history affects the reported parameters.

Properties and significance: Data on physical properties are limited and variable. Electrical behavior ranges from insulating to semiconducting, reflecting stoichiometry and defects. Magnetic measurements commonly indicate weak or paramagnetic behavior consistent with Ru3+. Because Ru2O3 is not a major commercial material, its primary value is academic, helping to map the ruthenium–oxygen system and serving as a potential precursor in the synthesis of other ruthenium oxides.

See also: Ruthenium oxide; RuO2; Ruthenium(III) oxide.