Materials Data on Sr(SmSe2)2 by Materials Project

Abstract

Sr(SmSe2)2 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. Sr2+ is bonded to eight equivalent Se2- atoms to form distorted SrSe8 hexagonal bipyramids that share corners with eight equivalent SmSe8 hexagonal bipyramids, edges with four equivalent SrSe8 hexagonal bipyramids, and faces with eight equivalent SmSe8 hexagonal bipyramids. There are four shorter (3.08 Å) and four longer (3.26 Å) Sr–Se bond lengths. Sm3+ is bonded to eight equivalent Se2- atoms to form distorted SmSe8 hexagonal bipyramids that share corners with four equivalent SrSe8 hexagonal bipyramids, corners with four equivalent SmSe8 hexagonal bipyramids, edges with four equivalent SmSe8 hexagonal bipyramids, faces with four equivalent SrSe8 hexagonal bipyramids, and faces with four equivalent SmSe8 hexagonal bipyramids. There are a spread of Sm–Se bond distances ranging from 2.95–3.23 Å. Se2- is bonded in a 6-coordinate geometry to two equivalent Sr2+ and four equivalent Sm3+ atoms.