Materials Data on K2NaFeF6 by Materials Project

Abstract

K2NaFeF6 is (Cubic) Perovskite-derived structured and 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, faces with four equivalent NaF6 octahedra, and faces with four equivalent FeF6 octahedra. All K–F bond lengths are 3.00 Å. Na1+ is bonded to six equivalent F1- atoms to form NaF6 octahedra that share corners with six equivalent FeF6 octahedra and faces with eight equivalent KF12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Na–F bond lengths are 2.27 Å. Fe3+ is bonded to six equivalent F1- atoms to form FeF6 octahedra that share corners with six equivalent NaF6 octahedra and faces with eight equivalent KF12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Fe–F bond lengths are 1.96 Å. F1- is bonded in a distorted linear geometry to four equivalent K1+, one Na1+, and one Fe3+ atom.