A new potassium niobate, KNb₅O₁₃

The structure of KNb₅O₁₃ consists of two-dimensional slabs of edge- and corner-sharing NbO₆ octa­hedra, and these slabs are inter­connected to form the three-dimensional framework. The K⁺ cations reside in the empty channels. Among the three crystallographically independent Nb atoms, the coordination around the Nb atom bridging the slabs is more regular than those of the other Nb atoms. A bond-valence calculation indicates that the charge balance should be represented by [K⁺][Nb⁵⁺]₅[O^2-]₁₃.