DOI: 10.17188/1206819
title: Materials Data on Sr(La2Se3)4 by Materials Project

description: Sr(La2Se3)4 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. Sr2+ is bonded to eight Se2- atoms to form distorted SrSe8 hexagonal bipyramids that share corners with eight LaSe8 hexagonal bipyramids, edges with four LaSe8 hexagonal bipyramids, and faces with eight LaSe8 hexagonal bipyramids. There are a spread of Sr–Se bond distances ranging from 3.11–3.29 Å. There are eight inequivalent La+2.75+ sites. In the first La+2.75+ site, La+2.75+ is bonded to eight Se2- atoms to form distorted LaSe8 hexagonal bipyramids that share corners with eight LaSe8 hexagonal bipyramids, edges with two equivalent SrSe8 hexagonal bipyramids, edges with two LaSe8 hexagonal bipyramids, and faces with eight LaSe8 hexagonal bipyramids. There are a spread of La–Se bond distances ranging from 3.07–3.25 Å. In the second La+2.75+ site, La+2.75+ is bonded to eight Se2- atoms to form distorted LaSe8 hexagonal bipyramids that share corners with two equivalent SrSe8 hexagonal bipyramids, corners with six LaSe8 hexagonal bipyramids, edges with four LaSe8 hexagonal bipyramids, a faceface with one SrSe8 hexagonal bipyramid, and faces with seven LaSe8 hexagonal bipyramids. There are a spread of La–Se bond distances ranging from 3.05–3.26 Å. In the third La+2.75+ site, La+2.75+ is bonded to eight Se2- atoms to form distorted LaSe8 hexagonal bipyramids that share a cornercorner with one SrSe8 hexagonal bipyramid, corners with seven LaSe8 hexagonal bipyramids, an edgeedge with one SrSe8 hexagonal bipyramid, edges with three LaSe8 hexagonal bipyramids, a faceface with one SrSe8 hexagonal bipyramid, and faces with seven LaSe8 hexagonal bipyramids. There are a spread of La–Se bond distances ranging from 3.07–3.25 Å. In the fourth La+2.75+ site, La+2.75+ is bonded to eight Se2- atoms to form distorted LaSe8 hexagonal bipyramids that share a cornercorner with one SrSe8 hexagonal bipyramid, corners with seven LaSe8 hexagonal bipyramids, edges with four LaSe8 hexagonal bipyramids, a faceface with one SrSe8 hexagonal bipyramid, and faces with seven LaSe8 hexagonal bipyramids. There are a spread of La–Se bond distances ranging from 3.07–3.25 Å. In the fifth La+2.75+ site, La+2.75+ is bonded to eight Se2- atoms to form distorted LaSe8 hexagonal bipyramids that share corners with eight LaSe8 hexagonal bipyramids, edges with four LaSe8 hexagonal bipyramids, faces with two equivalent SrSe8 hexagonal bipyramids, and faces with six LaSe8 hexagonal bipyramids. There are a spread of La–Se bond distances ranging from 3.08–3.26 Å. In the sixth La+2.75+ site, La+2.75+ is bonded to eight Se2- atoms to form distorted LaSe8 hexagonal bipyramids that share a cornercorner with one SrSe8 hexagonal bipyramid, corners with seven LaSe8 hexagonal bipyramids, edges with four LaSe8 hexagonal bipyramids, a faceface with one SrSe8 hexagonal bipyramid, and faces with seven LaSe8 hexagonal bipyramids. There are a spread of La–Se bond distances ranging from 3.05–3.25 Å. In the seventh La+2.75+ site, La+2.75+ is bonded to eight Se2- atoms to form distorted LaSe8 hexagonal bipyramids that share a cornercorner with one SrSe8 hexagonal bipyramid, corners with seven LaSe8 hexagonal bipyramids, an edgeedge with one SrSe8 hexagonal bipyramid, edges with three LaSe8 hexagonal bipyramids, a faceface with one SrSe8 hexagonal bipyramid, and faces with seven LaSe8 hexagonal bipyramids. There are a spread of La–Se bond distances ranging from 3.05–3.25 Å. In the eighth La+2.75+ site, La+2.75+ is bonded to eight Se2- atoms to form distorted LaSe8 hexagonal bipyramids that share corners with two equivalent SrSe8 hexagonal bipyramids, corners with six LaSe8 hexagonal bipyramids, edges with four LaSe8 hexagonal bipyramids, a faceface with one SrSe8 hexagonal bipyramid, and faces with seven LaSe8 hexagonal bipyramids. There are a spread of La–Se bond distances ranging from 3.05–3.25 Å. There are twelve inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to one Sr2+ and five La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeSrLa5 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the second Se2- site, Se2- is bonded to one Sr2+ and five La+2.75+ atoms to form distorted SeSrLa5 octahedra that share corners with fifteen SeSrLa5 octahedra, edges with six SeSrLa5 octahedra, and faces with five SeLa6 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the third Se2- site, Se2- is bonded to one Sr2+ and five La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeSrLa5 octahedra. The corner-sharing octahedra tilt angles range from 16–50°. In the fourth Se2- site, Se2- is bonded to one Sr2+ and five La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeSrLa5 octahedra. The corner-sharing octahedra tilt angles range from 17–51°. In the fifth Se2- site, Se2- is bonded to six La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeLa6 octahedra. The corner-sharing octahedra tilt angles range from 16–50°. In the sixth Se2- site, Se2- is bonded to six La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeLa6 octahedra. The corner-sharing octahedra tilt angles range from 16–50°. In the seventh Se2- site, Se2- is bonded to one Sr2+ and five La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeSrLa5 octahedra. The corner-sharing octahedra tilt angles range from 16–50°. In the eighth Se2- site, Se2- is bonded to one Sr2+ and five La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeSrLa5 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the ninth Se2- site, Se2- is bonded to six La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeLa6 octahedra. The corner-sharing octahedra tilt angles range from 16–50°. In the tenth Se2- site, Se2- is bonded to one Sr2+ and five La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeSrLa5 octahedra. The corner-sharing octahedra tilt angles range from 17–51°. In the eleventh Se2- site, Se2- is bonded to six La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeLa6 octahedra. The corner-sharing octahedra tilt angles range from 17–50°. In the twelfth Se2- site, Se2- is bonded to one Sr2+ and five La+2.75+ atoms to form a mixture of distorted corner, edge, and face-sharing SeSrLa5 octahedra. The corner-sharing octahedra tilt angles range from 17–50°.