Materials Data on K2NiF6 by Materials Project
K2NiF6 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. 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, and faces with four equivalent NiF6 octahedra. All K–F bond lengths are 2.92 Å. Ni4+ is bonded to six equivalent F1- atoms to form NiF6 octahedra that share faces with eight equivalent KF12 cuboctahedra. All Ni–F bond lengths are 1.80 Å. F1- is bonded in a single-bond geometry to four equivalent K1+ and one Ni4+ atom.
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