Materials Data on SrLaTl(AsO4)2 by Materials Project

Abstract

TlSrLa(AsO4)2 crystallizes in the trigonal P3_2 space group. The structure is three-dimensional. Sr2+ is bonded to eight O2- atoms to form distorted SrO8 hexagonal bipyramids that share corners with four AsO4 tetrahedra, edges with four equivalent LaO8 hexagonal bipyramids, and edges with two AsO4 tetrahedra. There are a spread of Sr–O bond distances ranging from 2.52–2.84 Å. La3+ is bonded to eight O2- atoms to form distorted LaO8 hexagonal bipyramids that share corners with four AsO4 tetrahedra, edges with four equivalent SrO8 hexagonal bipyramids, and edges with two AsO4 tetrahedra. There are a spread of La–O bond distances ranging from 2.45–2.73 Å. Tl1+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of Tl–O bond distances ranging from 2.94–3.55 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent SrO8 hexagonal bipyramids, corners with two equivalent LaO8 hexagonal bipyramids, an edgeedge with one SrO8 hexagonal bipyramid, and an edgeedge with one LaO8 hexagonal bipyramid. There is two shorter (1.72 Å) and two longer (1.73 Å) As–O bond length. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent SrO8 hexagonal bipyramids, corners with two equivalent LaO8 hexagonal bipyramids, an edgeedge with one SrO8 hexagonal bipyramid, and an edgeedge with one LaO8 hexagonal bipyramid. There is two shorter (1.72 Å) and two longer (1.73 Å) As–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one La3+, one Tl1+, and one As5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one La3+, one Tl1+, and one As5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one La3+, one Tl1+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one La3+, one Tl1+, and one As5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one La3+, one Tl1+, and one As5+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+, one La3+, one Tl1+, and one As5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one La3+, one Tl1+, and one As5+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one La3+, one Tl1+, and one As5+ atom.