Materials Data on K3Cu11Te16 by Materials Project

Abstract

K3Cu11Te16 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 1-coordinate geometry to eight Te+0.88- atoms. There are a spread of K–Te bond distances ranging from 3.45–3.95 Å. In the second K1+ site, K1+ is bonded to twelve Te+0.88- atoms to form KTe12 cuboctahedra that share corners with fourteen CuTe4 tetrahedra, edges with two equivalent KTe12 cuboctahedra, and faces with eight CuTe4 tetrahedra. There are a spread of K–Te bond distances ranging from 3.68–3.85 Å. There are four inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four Te+0.88- atoms to form CuTe4 tetrahedra that share a cornercorner with one KTe12 cuboctahedra, corners with four CuTe4 tetrahedra, edges with two CuTe4 tetrahedra, and a faceface with one KTe12 cuboctahedra. There are a spread of Cu–Te bond distances ranging from 2.60–2.73 Å. In the second Cu1+ site, Cu1+ is bonded to four Te+0.88- atoms to form CuTe4 tetrahedra that share a cornercorner with one KTe12 cuboctahedra, corners with seven CuTe4 tetrahedra, an edgeedge with one CuTe4 tetrahedra, and a faceface with one KTe12 cuboctahedra. There are a spread of Cu–Te bond distances ranging from 2.58–2.65 Å. In the third Cu1+ site, Cu1+ is bonded to four Te+0.88- atoms to form CuTe4 tetrahedra that share corners with two equivalent KTe12 cuboctahedra and corners with four equivalent CuTe4 tetrahedra. All Cu–Te bond lengths are 2.61 Å. In the fourth Cu1+ site, Cu1+ is bonded to four Te+0.88- atoms to form distorted CuTe4 tetrahedra that share corners with two equivalent KTe12 cuboctahedra, corners with four equivalent CuTe4 tetrahedra, and edges with two equivalent CuTe4 tetrahedra. There are two shorter (2.59 Å) and two longer (2.60 Å) Cu–Te bond lengths. There are six inequivalent Te+0.88- sites. In the first Te+0.88- site, Te+0.88- is bonded in a 6-coordinate geometry to two equivalent K1+, three Cu1+, and one Te+0.88- atom. The Te–Te bond length is 2.89 Å. In the second Te+0.88- site, Te+0.88- is bonded in a distorted trigonal non-coplanar geometry to three K1+ and three Cu1+ atoms. In the third Te+0.88- site, Te+0.88- is bonded in a 7-coordinate geometry to two equivalent K1+, four Cu1+, and one Te+0.88- atom. The Te–Te bond length is 2.93 Å. In the fourth Te+0.88- site, Te+0.88- is bonded in a 3-coordinate geometry to one K1+ and three Cu1+ atoms. In the fifth Te+0.88- site, Te+0.88- is bonded in a 2-coordinate geometry to one K1+ and two equivalent Cu1+ atoms. In the sixth Te+0.88- site, Te+0.88- is bonded in a 2-coordinate geometry to two equivalent K1+, one Cu1+, and two equivalent Te+0.88- atoms.