Materials Data on Er2Cu2O5 by Materials Project

Er2Cu2O5 is Spinel-like structured and crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are two inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing ErO6 octahedra. The corner-sharing octahedra tilt angles range from 21–64°. There are a spread of Er–O bond distances ranging from 2.22–2.29 Å. In the second Er3+ site, Er3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing ErO6 octahedra. The corner-sharing octahedra tilt angles range from 21–64°. There are a spread of Er–O bond distances ranging from 2.21–2.29 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.94–2.02 Å. In the second Cu2+ site, Cu2+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.95–2.01 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to three Er3+ and one Cu2+ atom to form distorted OEr3Cu tetrahedra that share corners with six OEr3Cu tetrahedra, corners with six OEr2Cu2 trigonal pyramids, and an edgeedge with one OEr2Cu2 trigonal pyramid. In the second O2- site, O2- is bonded to three Er3+ and one Cu2+ atom to form OEr3Cu tetrahedra that share corners with six OEr3Cu tetrahedra, corners with six OEr2Cu2 trigonal pyramids, and an edgeedge with one OEr2Cu2 trigonal pyramid. In the third O2- site, O2- is bonded to two equivalent Er3+ and two Cu2+ atoms to form distorted OEr2Cu2 trigonal pyramids that share corners with six OEr3Cu tetrahedra, corners with two equivalent OEr2Cu2 trigonal pyramids, an edgeedge with one OEr3Cu tetrahedra, and an edgeedge with one OEr2Cu2 trigonal pyramid. In the fourth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Er3+ and two Cu2+ atoms. In the fifth O2- site, O2- is bonded to two equivalent Er3+ and two Cu2+ atoms to form OEr2Cu2 trigonal pyramids that share corners with six OEr3Cu tetrahedra, corners with two equivalent OEr2Cu2 trigonal pyramids, an edgeedge with one OEr3Cu tetrahedra, and an edgeedge with one OEr2Cu2 trigonal pyramid.