A potassium sodium double salt of metavanadate, KNa(VO3)2.

Potassium sodium metavanadate, KNa(VO3)2, crystallizes with the pyroxene structure and is made up of VO4 tetrahedral chains, NaO6 octahedra and KO8 dodecahedra. The chains of corner-sharing VO4 tetrahedra are crosslinked through the NaO6 octahedra and KO8 dodecahedra to form a three-dimensional structure with the K+ and Na+ cations, which lie on twofold axes, situated in the void space. The coordination around the Na+ ion is close to normal octahedral, while the O atoms coordinated to the K+ ion are arranged approximately in a dodecahedral fashion.