Materials Data on Er4(GeO5)3 by Materials Project
Er4(GeO5)3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Er sites. In the first Er site, Er is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Er–O bond distances ranging from 2.27–2.58 Å. In the second Er site, Er is bonded to seven O atoms to form ErO7 pentagonal bipyramids that share a cornercorner with one ErO7 pentagonal bipyramid, corners with two equivalent GeO4 tetrahedra, and edges with two equivalent ErO7 pentagonal bipyramids. There are a spread of Er–O bond distances ranging from 2.23–2.37 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded to six O atoms to form GeO6 octahedra that share corners with two equivalent GeO6 octahedra and corners with four equivalent GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. All Ge–O bond lengths are 1.92 Å. In the second Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with two equivalent GeO6 octahedra and corners with two equivalent ErO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 60°. There are a spread of Ge–O bond distances ranging from 1.75–1.78 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to two Er and one Ge atom. In the second O site, O is bonded in a trigonal planar geometry to two Er and one Ge atom. In the third O site, O is bonded to two equivalent Er and two equivalent Ge atoms to form distorted corner-sharing OEr2Ge2 tetrahedra. In the fourth O site, O is bonded in a distorted trigonal non-coplanar geometry to three Er atoms. In the fifth O site, O is bonded in a water-like geometry to two equivalent Er atoms. In the sixth O site, O is bonded in a linear geometry to two equivalent Er atoms. In the seventh O site, O is bonded in a trigonal planar geometry to one Er and two Ge atoms.