Materials Data on K2RbNbF6 by Materials Project
RbK2NbF6 is (Cubic) Perovskite-derived structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Rb1+ is bonded to six equivalent F1- atoms to form RbF6 octahedra that share corners with six equivalent NbF6 octahedra and faces with eight equivalent KF12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Rb–F bond lengths are 2.63 Å. K1+ is bonded to twelve equivalent F1- atoms to form KF12 cuboctahedra that share corners with twelve equivalent KF12 cuboctahedra, faces with six equivalent KF12 cuboctahedra, faces with four equivalent RbF6 octahedra, and faces with four equivalent NbF6 octahedra. All K–F bond lengths are 3.36 Å. Nb3+ is bonded to six equivalent F1- atoms to form NbF6 octahedra that share corners with six equivalent RbF6 octahedra and faces with eight equivalent KF12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Nb–F bond lengths are 2.11 Å. F1- is bonded in a distorted linear geometry to one Rb1+, four equivalent K1+, and one Nb3+ atom.