Materials Data on KCdCu7Se2Cl9O8 by Materials Project
KCu7CdSe2O8Cl9 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six equivalent Cl1- atoms. All K–Cl bond lengths are 3.18 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to three O2- and three Cl1- atoms to form distorted CuCl3O3 octahedra that share a cornercorner with one CuCl3O3 octahedra, corners with two equivalent CdCl6 octahedra, edges with three equivalent CuCl3O3 octahedra, and an edgeedge with one CuCl3O2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 27–53°. There are two shorter (1.92 Å) and one longer (2.19 Å) Cu–O bond lengths. There are one shorter (2.56 Å) and two longer (2.61 Å) Cu–Cl bond lengths. In the second Cu2+ site, Cu2+ is bonded to two equivalent O2- and three equivalent Cl1- atoms to form edge-sharing CuCl3O2 trigonal bipyramids. Both Cu–O bond lengths are 1.92 Å. All Cu–Cl bond lengths are 2.42 Å. Cd2+ is bonded to six equivalent Cl1- atoms to form CdCl6 octahedra that share corners with twelve equivalent CuCl3O3 octahedra. The corner-sharing octahedral tilt angles are 53°. All Cd–Cl bond lengths are 2.66 Å. Se4+ is bonded in a distorted trigonal non-coplanar geometry to three equivalent O2- atoms. All Se–O bond lengths are 1.74 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Cu2+ and one Se4+ atom. In the second O2- site, O2- is bonded to four Cu2+ atoms to form corner-sharing OCu4 tetrahedra. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted T-shaped geometry to three Cu2+ atoms. In the second Cl1- site, Cl1- is bonded in a 4-coordinate geometry to one K1+, two equivalent Cu2+, and one Cd2+ atom.