Materials Data on Ti6Tl5AgSe27 by Materials Project

Abstract

Ti6AgTl5Se27 crystallizes in the trigonal P31c space group. The structure is three-dimensional. there are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to seven Se+1.11- atoms to form distorted TiSe7 pentagonal bipyramids that share a cornercorner with one AgSe6 octahedra, an edgeedge with one TiSe7 pentagonal bipyramid, and a faceface with one TiSe7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 54°. There are a spread of Ti–Se bond distances ranging from 2.54–2.73 Å. In the second Ti4+ site, Ti4+ is bonded to seven Se+1.11- atoms to form distorted TiSe7 pentagonal bipyramids that share a cornercorner with one AgSe6 octahedra, an edgeedge with one TiSe7 pentagonal bipyramid, and a faceface with one TiSe7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 57°. There are a spread of Ti–Se bond distances ranging from 2.54–2.78 Å. Ag1+ is bonded to six Se+1.11- atoms to form AgSe6 octahedra that share corners with six TiSe7 pentagonal bipyramids. There are three shorter (2.87 Å) and three longer (2.90 Å) Ag–Se bond lengths. There are three inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 9-coordinate geometry to nine Se+1.11- atoms. There are a spread of Tl–Se bond distances ranging from 3.33–3.73 Å. In the second Tl1+ site, Tl1+ is bonded in a 5-coordinate geometry to six Se+1.11- atoms. There are a spread of Tl–Se bond distances ranging from 3.22–3.73 Å. In the third Tl1+ site, Tl1+ is bonded in a 12-coordinate geometry to twelve Se+1.11- atoms. There are a spread of Tl–Se bond distances ranging from 3.48–4.02 Å. There are nine inequivalent Se+1.11- sites. In the first Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two Ti4+, one Tl1+, and one Se+1.11- atom. The Se–Se bond length is 2.39 Å. In the second Se+1.11- site, Se+1.11- is bonded in a 6-coordinate geometry to two Ti4+ and four Tl1+ atoms. In the third Se+1.11- site, Se+1.11- is bonded in a 1-coordinate geometry to one Ti4+ and one Tl1+ atom. In the fourth Se+1.11- site, Se+1.11- is bonded in a 4-coordinate geometry to one Ti4+, one Ag1+, one Tl1+, and one Se+1.11- atom. The Se–Se bond length is 2.43 Å. In the fifth Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two Ti4+ and one Tl1+ atom. In the sixth Se+1.11- site, Se+1.11- is bonded in a 1-coordinate geometry to one Ti4+ and two Tl1+ atoms. In the seventh Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two Ti4+ and one Tl1+ atom. In the eighth Se+1.11- site, Se+1.11- is bonded in a 4-coordinate geometry to one Ti4+, one Ag1+, one Tl1+, and one Se+1.11- atom. In the ninth Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two Ti4+, one Tl1+, and one Se+1.11- atom.