Materials Data on La3NbSe2(O2F)2 by Materials Project

Abstract

La3NbSe2O4F2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to five Se2-, three O2-, and one F1- atom. There are two shorter (3.15 Å) and three longer (3.17 Å) La–Se bond lengths. There are two shorter (2.51 Å) and one longer (2.72 Å) La–O bond lengths. The La–F bond length is 2.56 Å. In the second La3+ site, La3+ is bonded in a 7-coordinate geometry to two equivalent Se2-, two O2-, and five F1- atoms. Both La–Se bond lengths are 3.16 Å. There are one shorter (2.54 Å) and one longer (2.59 Å) La–O bond lengths. There are a spread of La–F bond distances ranging from 2.43–2.63 Å. In the third La3+ site, La3+ is bonded in a 9-coordinate geometry to three Se2-, five O2-, and one F1- atom. There are two shorter (3.08 Å) and one longer (3.17 Å) La–Se bond lengths. There are a spread of La–O bond distances ranging from 2.54–2.72 Å. The La–F bond length is 2.43 Å. Nb5+ is bonded to one Se2- and five O2- atoms to form distorted corner-sharing NbSeO5 trigonal bipyramids. The Nb–Se bond length is 2.99 Å. There are a spread of Nb–O bond distances ranging from 1.85–2.05 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to five La3+ atoms. In the second Se2- site, Se2- is bonded in a 7-coordinate geometry to five La3+ and one Nb5+ atom. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Nb5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent La3+ and one Nb5+ atom. In the fourth O2- site, O2- is bonded to three La3+ and one Nb5+ atom to form distorted OLa3Nb tetrahedra that share a cornercorner with one FLa4 tetrahedra, corners with two equivalent OLa3Nb tetrahedra, and edges with two equivalent FLa4 tetrahedra. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to four La3+ atoms to form distorted FLa4 tetrahedra that share a cornercorner with one OLa3Nb tetrahedra, corners with two equivalent FLa4 tetrahedra, edges with two equivalent OLa3Nb tetrahedra, and edges with two equivalent FLa4 tetrahedra. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to three La3+ atoms.