Materials Data on Tb3CrSe6 by Materials Project

Abstract

Tb3CrSe6 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. there are three inequivalent Tb3+ sites. In the first Tb3+ site, Tb3+ is bonded to seven Se2- atoms to form distorted TbSe7 pentagonal bipyramids that share a cornercorner with one CrSe6 octahedra, edges with two equivalent CrSe6 octahedra, and edges with two equivalent TbSe7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 33°. There are a spread of Tb–Se bond distances ranging from 2.86–3.00 Å. In the second Tb3+ site, Tb3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Tb–Se bond distances ranging from 2.92–3.06 Å. In the third Tb3+ site, Tb3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Tb–Se bond distances ranging from 2.91–3.28 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 edges with two equivalent CrSe6 octahedra and edges with four equivalent TbSe7 pentagonal bipyramids. There are two shorter (2.55 Å) and four longer (2.59 Å) Cr–Se bond lengths. In the second Cr3+ site, Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with two equivalent TbSe7 pentagonal bipyramids and edges with two equivalent CrSe6 octahedra. There are two shorter (2.49 Å) and four longer (2.62 Å) Cr–Se bond lengths. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to three Tb3+ and two equivalent Cr3+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to three Tb3+ and two equivalent Cr3+ atoms. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to five Tb3+ atoms. In the fourth Se2- site, Se2- is bonded to three Tb3+ and one Cr3+ atom to form distorted SeTb3Cr trigonal pyramids that share corners with four SeTb5 trigonal bipyramids, corners with three equivalent SeTb3Cr trigonal pyramids, and a faceface with one SeTb5 trigonal bipyramid. In the fifth Se2- site, Se2- is bonded to five Tb3+ atoms to form distorted SeTb5 trigonal bipyramids that share corners with four equivalent SeTb4Cr trigonal bipyramids, corners with two equivalent SeTb3Cr trigonal pyramids, edges with three SeTb5 trigonal bipyramids, and a faceface with one SeTb3Cr trigonal pyramid. In the sixth Se2- site, Se2- is bonded to four Tb3+ and one Cr3+ atom to form distorted SeTb4Cr trigonal bipyramids that share corners with five SeTb5 trigonal bipyramids, corners with two equivalent SeTb3Cr trigonal pyramids, and edges with three SeTb5 trigonal bipyramids.