ErY(FeO3)2 crystallizes in the orthorhombic Pmc2_1 space group. Er(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. Y(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(4), and four equivalent O(3) atoms. Fe(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 37-40°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Y(1) and two equivalent Fe(1) atoms to form distorted OY2Fe2 trigonal pyramids that share corners with two equivalent O(2)Er2Fe2 trigonal pyramids and corners with two equivalent O(1)Y2Fe2 trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Er(1) and two equivalent Fe(1) atoms to form distorted OEr2Fe2 trigonal pyramids that share corners with two equivalent O(2)Er2Fe2 trigonal pyramids and corners with two equivalent O(1)Y2Fe2 trigonal pyramids. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Er(1), two equivalent Y(1), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Er(1), one Y(1), and two equivalent Fe(1) atoms.
ErY(FeO3)2 crystallizes in the orthorhombic Pmc2_1 space group. Er(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. There is one shorter (2.22 Å) and one longer (2.29 Å) Er(1)-O(2) bond length. Both Er(1)-O(3) bond lengths are 2.72 Å. There are two shorter (2.26 Å) and two longer (2.49 Å) Er(1)-O(4) bond lengths. Y(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(4), and four equivalent O(3) atoms. There is one shorter (2.24 Å) and one longer (2.30 Å) Y(1)-O(1) bond length. Both Y(1)-O(4) bond lengths are 2.76 Å. There are two shorter (2.28 Å) and two longer (2.51 Å) Y(1)-O(3) bond lengths. Fe(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 37-40°. The Fe(1)-O(1) bond length is 2.05 Å. The Fe(1)-O(2) bond length is 2.04 Å. There is one shorter (2.03 Å) and one longer (2.05 Å) Fe(1)-O(3) bond length. There is one shorter (2.03 Å) and one longer (2.06 Å) Fe(1)-O(4) bond length. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Y(1) and two equivalent Fe(1) atoms to form distorted OY2Fe2 trigonal pyramids that share corners with two equivalent O(2)Er2Fe2 trigonal pyramids and corners with two equivalent O(1)Y2Fe2 trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Er(1) and two equivalent Fe(1) atoms to form distorted OEr2Fe2 trigonal pyramids that share corners with two equivalent O(2)Er2Fe2 trigonal pyramids and corners with two equivalent O(1)Y2Fe2 trigonal pyramids. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Er(1), two equivalent Y(1), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Er(1), one Y(1), and two equivalent Fe(1) atoms.