Ta2O6

Ta2O6 is a chemical compound consisting of tantalum and oxygen with the empirical formula Ta2O6. It is far less common and less well characterized than the more familiar Ta2O5, and in the literature it is often discussed as a non-stoichiometric or metastable tantalum oxide phase rather than a stable bulk compound.

The precise crystallography of Ta2O6 is not universally agreed, and reported structures vary with synthesis conditions. It is generally described as existing in a polymeric network of TaO6 octahedra, and several polymorphs may be present depending on temperature, pressure, and oxygen content. Because Ta2O6 lies between more reduced tantalum oxides and Ta2O5 in composition, its phase behavior is often considered in the context of non-stoichiometric Ta2O5−x or Ta2O6±δ systems rather than a single well-defined oxide.

Synthesis and occurrence: Ta2O6 has been reported in various experimental contexts, including high-temperature oxidation, thin-film deposition, and other routes that involve careful control of oxygen partial pressure. In many discussions, Ta2O6 is described as a transient or metastable phase rather than a stable bulk phase, and its formation may depend on rapid quenching, specific substrate effects, or other processing parameters.

Properties and applications: There is limited, scattered data on the physical properties of Ta2O6. Like other tantalum oxides, it is expected to exhibit high thermal stability, but its electrical, optical, and dielectric properties are not well established and appear to vary with preparation. Consequently, Ta2O6 has no widely adopted industrial applications and is mainly of interest to researchers studying the complex phase relations in tantalum–oxygen systems.

See also: Ta2O5, tantalum oxide.