Materials Data on Eu2Ru2O7 by Materials Project
Eu2Ru2O7 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Eu3+ sites. In the first Eu3+ site, Eu3+ is bonded to eight O2- atoms to form distorted EuO8 hexagonal bipyramids that share edges with six EuO8 hexagonal bipyramids and edges with six RuO6 octahedra. There are a spread of Eu–O bond distances ranging from 2.27–2.60 Å. In the second Eu3+ site, Eu3+ is bonded to eight O2- atoms to form distorted EuO8 hexagonal bipyramids that share edges with six equivalent EuO8 hexagonal bipyramids and edges with six equivalent RuO6 octahedra. There are two shorter (2.29 Å) and six longer (2.59 Å) Eu–O bond lengths. There are two inequivalent Ru4+ sites. In the first Ru4+ site, Ru4+ is bonded to six O2- atoms to form RuO6 octahedra that share corners with six RuO6 octahedra and edges with six EuO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. All Ru–O bond lengths are 2.03 Å. In the second Ru4+ site, Ru4+ is bonded to six equivalent O2- atoms to form RuO6 octahedra that share corners with six equivalent RuO6 octahedra and edges with six equivalent EuO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. All Ru–O bond lengths are 2.03 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Eu3+ and two Ru4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Eu3+ and two equivalent Ru4+ atoms. In the third O2- site, O2- is bonded to four Eu3+ atoms to form corner-sharing OEu4 tetrahedra.