Materials Data on SrCeCuSe3 by Materials Project
SrCeCuSe3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Sr2+ is bonded to seven Se2- atoms to form distorted SrSe7 pentagonal bipyramids that share corners with three equivalent CeSe7 pentagonal bipyramids, corners with four equivalent CuSe4 tetrahedra, edges with five equivalent CeSe7 pentagonal bipyramids, edges with six equivalent SrSe7 pentagonal bipyramids, and edges with three equivalent CuSe4 tetrahedra. There are a spread of Sr–Se bond distances ranging from 3.08–3.24 Å. Ce3+ is bonded to seven Se2- atoms to form distorted CeSe7 pentagonal bipyramids that share corners with three equivalent SrSe7 pentagonal bipyramids, corners with four equivalent CeSe7 pentagonal bipyramids, edges with two equivalent CeSe7 pentagonal bipyramids, edges with five equivalent SrSe7 pentagonal bipyramids, edges with four equivalent CuSe4 tetrahedra, and faces with two equivalent CeSe7 pentagonal bipyramids. There are a spread of Ce–Se bond distances ranging from 3.04–3.09 Å. Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with four equivalent SrSe7 pentagonal bipyramids, corners with two equivalent CuSe4 tetrahedra, edges with three equivalent SrSe7 pentagonal bipyramids, and edges with four equivalent CeSe7 pentagonal bipyramids. There are a spread of Cu–Se bond distances ranging from 2.43–2.45 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to three equivalent Sr2+, two equivalent Ce3+, and one Cu1+ atom. In the second Se2- site, Se2- is bonded to one Sr2+, four equivalent Ce3+, and one Cu1+ atom to form a mixture of distorted corner and edge-sharing SeSrCe4Cu octahedra. The corner-sharing octahedral tilt angles are 22°. In the third Se2- site, Se2- is bonded in a 6-coordinate geometry to three equivalent Sr2+, one Ce3+, and two equivalent Cu1+ atoms.