Materials Data on Eu2Cr2O5 by Materials Project
Eu2Cr2O5 crystallizes in the orthorhombic Ima2 space group. The structure is three-dimensional. Eu2+ is bonded in a 9-coordinate geometry to eight O2- atoms. There are a spread of Eu–O bond distances ranging from 2.38–2.86 Å. There are two inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with four equivalent CrO6 octahedra and corners with two equivalent CrO4 tetrahedra. The corner-sharing octahedral tilt angles are 12°. There are a spread of Cr–O bond distances ranging from 1.97–2.06 Å. In the second Cr3+ site, Cr3+ is bonded to four O2- atoms to form CrO4 tetrahedra that share corners with two equivalent CrO6 octahedra and corners with two equivalent CrO4 tetrahedra. The corner-sharing octahedral tilt angles are 26°. There are a spread of Cr–O bond distances ranging from 1.99–2.08 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to four equivalent Eu2+ and two equivalent Cr3+ atoms. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Eu2+ and two Cr3+ atoms. In the third O2- site, O2- is bonded to two equivalent Eu2+ and two equivalent Cr3+ atoms to form distorted corner-sharing OEu2Cr2 tetrahedra.