Materials Data on CsK2AsF6 by Materials Project
CsK2AsF6 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Cs1+ is bonded to six equivalent F1- atoms to form CsF6 octahedra that share corners with six equivalent AsF6 octahedra and faces with eight equivalent KF12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Cs–F bond lengths are 2.78 Å. K1+ is bonded to twelve equivalent F1- atoms to form distorted KF12 cuboctahedra that share corners with twelve equivalent KF12 cuboctahedra, faces with six equivalent KF12 cuboctahedra, faces with four equivalent CsF6 octahedra, and faces with four equivalent AsF6 octahedra. All K–F bond lengths are 3.45 Å. As3+ is bonded to six equivalent F1- atoms to form AsF6 octahedra that share corners with six equivalent CsF6 octahedra and faces with eight equivalent KF12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All As–F bond lengths are 2.07 Å. F1- is bonded in a distorted linear geometry to one Cs1+, four equivalent K1+, and one As3+ atom.