inorganic compounds
The structure of K3Nb3O6Si2O7 is built up from Si2O7 ditetrahedra and groups
of three corner-linked NbO6 octahedra. The framework is isotypic with that of Ba3Nb6O12(Si2O7)2, but the filling
of the tunnels with K+ ions rather than Ba2+ ions determines the space
group to be P\=62c.