Materials Data on Yb5Se7 by Materials Project
Yb5Se7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are five inequivalent Yb+2.80+ sites. In the first Yb+2.80+ site, Yb+2.80+ is bonded to six Se2- atoms to form YbSe6 octahedra that share corners with three YbSe6 octahedra, corners with two equivalent YbSe7 pentagonal bipyramids, edges with five YbSe6 octahedra, and edges with five YbSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 0–79°. There are a spread of Yb–Se bond distances ranging from 2.79–3.05 Å. In the second Yb+2.80+ site, Yb+2.80+ is bonded to six Se2- atoms to form YbSe6 octahedra that share corners with three YbSe6 octahedra, corners with two equivalent YbSe7 pentagonal bipyramids, edges with five YbSe6 octahedra, and edges with five YbSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 0–79°. There are a spread of Yb–Se bond distances ranging from 2.79–3.05 Å. In the third Yb+2.80+ site, Yb+2.80+ is bonded to seven Se2- atoms to form distorted YbSe7 pentagonal bipyramids that share corners with six YbSe6 octahedra, a cornercorner with one YbSe7 pentagonal bipyramid, edges with six YbSe6 octahedra, and faces with two equivalent YbSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 5–50°. There are a spread of Yb–Se bond distances ranging from 2.86–3.33 Å. In the fourth Yb+2.80+ site, Yb+2.80+ is bonded to seven Se2- atoms to form distorted YbSe7 pentagonal bipyramids that share corners with six YbSe6 octahedra, a cornercorner with one YbSe7 pentagonal bipyramid, edges with six YbSe6 octahedra, and faces with two equivalent YbSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 5–49°. There are a spread of Yb–Se bond distances ranging from 2.86–3.34 Å. In the fifth Yb+2.80+ site, Yb+2.80+ is bonded to six Se2- atoms to form YbSe6 octahedra that share corners with two YbSe6 octahedra, corners with eight YbSe7 pentagonal bipyramids, edges with two equivalent YbSe6 octahedra, and edges with two YbSe7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 79°. There are a spread of Yb–Se bond distances ranging from 2.80–3.01 Å. There are seven inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to five Yb+2.80+ and one Se2- atom. The Se–Se bond length is 2.45 Å. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to five Yb+2.80+ and one Se2- atom. The Se–Se bond length is 2.45 Å. In the third Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to four Yb+2.80+ atoms. In the fourth Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to four Yb+2.80+ atoms. In the fifth Se2- site, Se2- is bonded in a 4-coordinate geometry to four Yb+2.80+ and one Se2- atom. In the sixth Se2- site, Se2- is bonded in a 4-coordinate geometry to four Yb+2.80+ and one Se2- atom. In the seventh Se2- site, Se2- is bonded to six Yb+2.80+ atoms to form edge-sharing SeYb6 octahedra.