Materials Data on K2Zr3OF12 by Materials Project

K2Zr3OF12 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to twelve F1- atoms to form face-sharing KF12 cuboctahedra. There are six shorter (2.74 Å) and six longer (3.15 Å) K–F bond lengths. In the second K1+ site, K1+ is bonded to twelve F1- atoms to form distorted corner-sharing KF12 cuboctahedra. The corner-sharing octahedral tilt angles are 66°. There are six shorter (2.75 Å) and six longer (3.10 Å) K–F bond lengths. In the third K1+ site, K1+ is bonded to six F1- atoms to form a mixture of corner and face-sharing KF6 octahedra. There are three shorter (2.72 Å) and three longer (2.84 Å) K–F bond lengths. Zr4+ is bonded in a 8-coordinate geometry to one O2- and seven F1- atoms. The Zr–O bond length is 2.09 Å. There are a spread of Zr–F bond distances ranging from 2.02–2.24 Å. O2- is bonded in a distorted trigonal planar geometry to three equivalent Zr4+ atoms. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one K1+ and two equivalent Zr4+ atoms. In the second F1- site, F1- is bonded in a 3-coordinate geometry to two K1+ and two equivalent Zr4+ atoms. In the third F1- site, F1- is bonded in a distorted trigonal planar geometry to one K1+ and two equivalent Zr4+ atoms. In the fourth F1- site, F1- is bonded in a 3-coordinate geometry to two K1+ and one Zr4+ atom.