DOI: 10.17188/1699078
title: Materials Data on Sr2Tl2O5 by Materials Project

description: Sr2Tl2O5 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to seven O2- atoms to form distorted SrO7 pentagonal bipyramids that share corners with four TlO6 octahedra, corners with five equivalent SrO6 octahedra, an edgeedge with one SrO6 octahedra, edges with five TlO6 octahedra, and faces with two equivalent SrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 3–67°. There are a spread of Sr–O bond distances ranging from 2.49–2.73 Å. In the second Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with three TlO6 octahedra, corners with five equivalent SrO7 pentagonal bipyramids, edges with two equivalent SrO6 octahedra, edges with five TlO6 octahedra, and an edgeedge with one SrO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 15–58°. There are a spread of Sr–O bond distances ranging from 2.41–2.59 Å. There are two inequivalent Tl3+ sites. In the first Tl3+ site, Tl3+ is bonded to six O2- atoms to form TlO6 octahedra that share corners with two equivalent SrO6 octahedra, corners with two equivalent TlO6 octahedra, corners with two equivalent SrO7 pentagonal bipyramids, edges with three equivalent SrO6 octahedra, edges with five TlO6 octahedra, and edges with two equivalent SrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 3–15°. There are a spread of Tl–O bond distances ranging from 2.15–2.54 Å. In the second Tl3+ site, Tl3+ is bonded to six O2- atoms to form TlO6 octahedra that share a cornercorner with one SrO6 octahedra, corners with two equivalent TlO6 octahedra, corners with two equivalent SrO7 pentagonal bipyramids, edges with two equivalent SrO6 octahedra, edges with five TlO6 octahedra, and edges with three equivalent SrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 3–58°. There are a spread of Tl–O bond distances ranging from 2.11–2.55 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to two Sr2+ and four Tl3+ atoms to form OSr2Tl4 octahedra that share corners with four OSr2Tl3 square pyramids, a cornercorner with one OSr3Tl tetrahedra, edges with two equivalent OSr2Tl4 octahedra, edges with six OSr2Tl3 square pyramids, and edges with two equivalent OSr3Tl tetrahedra. In the second O2- site, O2- is bonded to two equivalent Sr2+ and three Tl3+ atoms to form OSr2Tl3 square pyramids that share corners with two equivalent OSr2Tl4 octahedra, corners with three equivalent OSr3Tl tetrahedra, edges with three equivalent OSr2Tl4 octahedra, and edges with four OSr2Tl3 square pyramids. The corner-sharing octahedral tilt angles are 8°. In the third O2- site, O2- is bonded to three Sr2+ and one Tl3+ atom to form OSr3Tl tetrahedra that share a cornercorner with one OSr2Tl4 octahedra, corners with seven OSr2Tl3 square pyramids, corners with two equivalent OSr3Tl tetrahedra, edges with two equivalent OSr2Tl4 octahedra, and an edgeedge with one OSr2Tl3 square pyramid. The corner-sharing octahedral tilt angles are 6°. In the fourth O2- site, O2- is bonded to two equivalent Sr2+ and three Tl3+ atoms to form distorted OSr2Tl3 square pyramids that share corners with two equivalent OSr2Tl4 octahedra, corners with four equivalent OSr3Tl tetrahedra, edges with three equivalent OSr2Tl4 octahedra, edges with four OSr2Tl3 square pyramids, and an edgeedge with one OSr3Tl tetrahedra. The corner-sharing octahedral tilt angles are 7°. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Tl3+ atom.