Materials Data on CsEr3Se5 by Materials Project
CsEr3Se5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Cs1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.69–3.89 Å. There are three inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing ErSe6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are a spread of Er–Se bond distances ranging from 2.80–2.97 Å. In the second Er3+ site, Er3+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing ErSe6 octahedra. The corner-sharing octahedra tilt angles range from 1–12°. There are a spread of Er–Se bond distances ranging from 2.79–2.96 Å. In the third Er3+ site, Er3+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing ErSe6 octahedra. The corner-sharing octahedral tilt angles are 12°. There are a spread of Er–Se bond distances ranging from 2.81–2.90 Å. There are five inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Cs1+ and three Er3+ atoms. In the second Se2- site, Se2- is bonded in a 4-coordinate geometry to one Cs1+ and four Er3+ atoms. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Cs1+ and three Er3+ atoms. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Cs1+ and three Er3+ atoms. In the fifth Se2- site, Se2- is bonded to five Er3+ atoms to form edge-sharing SeEr5 square pyramids.