ErEu2TaO6 is (Cubic) Perovskite-derived structured and crystallizes in the cubic Fm-3m space group. Er(1) is bonded to six equivalent O(1) atoms to form ErO6 octahedra that share corners with six equivalent Ta(1)O6 octahedra and faces with eight equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. Eu(1) is bonded to twelve equivalent O(1) atoms to form EuO12 cuboctahedra that share corners with twelve equivalent Eu(1)O12 cuboctahedra, faces with six equivalent Eu(1)O12 cuboctahedra, faces with four equivalent Er(1)O6 octahedra, and faces with four equivalent Ta(1)O6 octahedra. Ta(1) is bonded to six equivalent O(1) atoms to form TaO6 octahedra that share corners with six equivalent Er(1)O6 octahedra and faces with eight equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. O(1) is bonded in a distorted linear geometry to one Er(1), four equivalent Eu(1), and one Ta(1) atom.
ErEu2TaO6 is (Cubic) Perovskite-derived structured and crystallizes in the cubic Fm-3m space group. Er(1) is bonded to six equivalent O(1) atoms to form ErO6 octahedra that share corners with six equivalent Ta(1)O6 octahedra and faces with eight equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. All Er(1)-O(1) bond lengths are 2.18 Å. Eu(1) is bonded to twelve equivalent O(1) atoms to form EuO12 cuboctahedra that share corners with twelve equivalent Eu(1)O12 cuboctahedra, faces with six equivalent Eu(1)O12 cuboctahedra, faces with four equivalent Er(1)O6 octahedra, and faces with four equivalent Ta(1)O6 octahedra. All Eu(1)-O(1) bond lengths are 2.95 Å. Ta(1) is bonded to six equivalent O(1) atoms to form TaO6 octahedra that share corners with six equivalent Er(1)O6 octahedra and faces with eight equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. All Ta(1)-O(1) bond lengths are 1.99 Å. O(1) is bonded in a distorted linear geometry to one Er(1), four equivalent Eu(1), and one Ta(1) atom.