DOE OSTI2020
Tl5Cu14Se10 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are seven inequivalent Cu+1.07+ sites. In the first Cu+1.07+ site, Cu+1.07+ is bonded in a trigonal planar geometry to three Se2- atoms. There are two shorter (2.47 Å) and one longer (2.49 Å) Cu–Se bond lengths. In the second Cu+1.07+ site, Cu+1.07+ is bonded in a trigonal planar geometry to three Se2- atoms. There are two shorter (2.47 Å) and one longer (2.51 Å) Cu–Se bond lengths. In the third Cu+1.07+ site, Cu+1.07+ is bonded in a distorted trigonal non-coplanar geometry to three Se2- atoms. There are one shorter (2.38 Å) and two longer (2.51 Å) Cu–Se bond lengths. In the fourth Cu+1.07+ site, Cu+1.07+ is bonded to four Se2- atoms to form a mixture of distorted corner and edge-sharing CuSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.40–2.69 Å. In the fifth Cu+1.07+ site, Cu+1.07+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Cu–Se bond distances ranging from 2.40–2.76 Å. In the sixth Cu+1.07+ site, Cu+1.07+ is bonded to four Se2- atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.48–2.58 Å. In the seventh Cu+1.07+ site, Cu+1.07+ is bonded in a distorted trigonal planar geometry to three Se2- atoms. There are one shorter (2.40 Å) and two longer (2.54 Å) Cu–Se bond lengths. There are three inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.27–3.73 Å. In the second Tl1+ site, Tl1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.34–3.57 Å. In the third Tl1+ site, Tl1+ is bonded in a body-centered cubic geometry to eight Se2- atoms. There are four shorter (3.37 Å) and four longer (3.47 Å) Tl–Se bond lengths. There are five inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 8-coordinate geometry to four Cu+1.07+ and four equivalent Tl1+ atoms. In the second Se2- site, Se2- is bonded in a 4-coordinate geometry to six Cu+1.07+ and three Tl1+ atoms. In the third Se2- site, Se2- is bonded in a 8-coordinate geometry to four Cu+1.07+ and four Tl1+ atoms. In the fourth Se2- site, Se2- is bonded in a 9-coordinate geometry to six Cu+1.07+ and three Tl1+ atoms. In the fifth Se2- site, Se2- is bonded in a 8-coordinate geometry to four Cu+1.07+ and four Tl1+ atoms.