Materials Data on Sm3CrSe6 by Materials Project

Abstract

Sm3CrSe6 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. there are three inequivalent Sm3+ sites. In the first Sm3+ site, Sm3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Sm–Se bond distances ranging from 2.96–3.35 Å. In the second Sm3+ site, Sm3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Sm–Se bond distances ranging from 2.97–3.11 Å. In the third Sm3+ site, Sm3+ is bonded to seven Se2- atoms to form distorted SmSe7 pentagonal bipyramids that share a cornercorner with one CrSe6 octahedra, edges with two equivalent CrSe6 octahedra, and edges with two equivalent SmSe7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 32°. There are a spread of Sm–Se bond distances ranging from 2.91–3.03 Å. There are two inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with two equivalent SmSe7 pentagonal bipyramids and edges with two equivalent CrSe6 octahedra. There are two shorter (2.50 Å) and four longer (2.63 Å) Cr–Se bond lengths. In the second Cr3+ site, Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share edges with two equivalent CrSe6 octahedra and edges with four equivalent SmSe7 pentagonal bipyramids. There are two shorter (2.56 Å) and four longer (2.61 Å) Cr–Se bond lengths. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to five Sm3+ atoms to form distorted SeSm5 trigonal bipyramids that share corners with four equivalent SeSm4Cr trigonal bipyramids, corners with two equivalent SeSm3Cr trigonal pyramids, edges with three SeSm5 trigonal bipyramids, and a faceface with one SeSm3Cr trigonal pyramid. In the second Se2- site, Se2- is bonded to four Sm3+ and one Cr3+ atom to form distorted SeSm4Cr trigonal bipyramids that share corners with five SeSm5 trigonal bipyramids, corners with two equivalent SeSm3Cr trigonal pyramids, and edges with three SeSm5 trigonal bipyramids. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to three Sm3+ and two equivalent Cr3+ atoms. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to three Sm3+ and two equivalent Cr3+ atoms. In the fifth Se2- site, Se2- is bonded in a 5-coordinate geometry to five Sm3+ atoms. In the sixth Se2- site, Se2- is bonded to three Sm3+ and one Cr3+ atom to form distorted SeSm3Cr trigonal pyramids that share corners with four SeSm5 trigonal bipyramids, corners with three equivalent SeSm3Cr trigonal pyramids, and a faceface with one SeSm5 trigonal bipyramid.