Materials Data on K8Zr6BBr20 by Materials Project
K8Zr6BBr20 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. K1+ is bonded in a 4-coordinate geometry to four Br1- atoms. There are one shorter (3.16 Å) and three longer (3.34 Å) K–Br bond lengths. Zr+2.50+ is bonded to one B3- and five Br1- atoms to form a mixture of corner and edge-sharing ZrBBr5 octahedra. The corner-sharing octahedral tilt angles are 0°. The Zr–B bond length is 2.33 Å. There are four shorter (2.75 Å) and one longer (2.92 Å) Zr–Br bond lengths. B3- is bonded to six equivalent Zr+2.50+ atoms to form BZr6 octahedra that share corners with six equivalent BrK4Zr square pyramids. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded to four equivalent K1+ and one Zr+2.50+ atom to form distorted BrK4Zr square pyramids that share a cornercorner with one BZr6 octahedra, corners with four equivalent BrK4 tetrahedra, and edges with four equivalent BrK4Zr square pyramids. The corner-sharing octahedral tilt angles are 0°. In the second Br1- site, Br1- is bonded to four equivalent K1+ atoms to form corner-sharing BrK4 tetrahedra. In the third Br1- site, Br1- is bonded in a 2-coordinate geometry to two equivalent Zr+2.50+ atoms.