Materials Data on Er3SiSe2O10F by Materials Project
Er3SiSe2O10F crystallizes in the orthorhombic Pnna space group. The structure is three-dimensional. there are two inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to six O2- and one F1- atom to form distorted ErO6F pentagonal bipyramids that share a cornercorner with one ErO6F pentagonal bipyramid, a cornercorner with one SiO4 tetrahedra, edges with two equivalent ErO6F pentagonal bipyramids, and an edgeedge with one SiO4 tetrahedra. There are a spread of Er–O bond distances ranging from 2.20–2.47 Å. The Er–F bond length is 2.21 Å. In the second Er3+ site, Er3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Er–O bond distances ranging from 2.26–2.40 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent ErO6F pentagonal bipyramids and edges with two equivalent ErO6F pentagonal bipyramids. All Si–O bond lengths are 1.65 Å. Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.73 Å) and one longer (1.75 Å) Se–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Er3+ and one Se4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Er3+ and one Se4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Er3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two Er3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Er3+ and one Se4+ atom. F1- is bonded in a distorted bent 150 degrees geometry to two equivalent Er3+ atoms.