Materials Data on ErCuPbSe3 by Materials Project
ErCuPbSe3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Er3+ is bonded to six Se2- atoms to form ErSe6 octahedra that share corners with two equivalent ErSe6 octahedra, edges with two equivalent ErSe6 octahedra, and edges with four equivalent CuSe4 tetrahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of Er–Se bond distances ranging from 2.84–2.88 Å. Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with two equivalent CuSe4 tetrahedra and edges with four equivalent ErSe6 octahedra. There are a spread of Cu–Se bond distances ranging from 2.44–2.52 Å. Pb2+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Pb–Se bond distances ranging from 3.14–3.40 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to two equivalent Er3+, two equivalent Cu1+, and two equivalent Pb2+ atoms. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Er3+, one Cu1+, and three equivalent Pb2+ atoms. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Er3+, one Cu1+, and two equivalent Pb2+ atoms.