KErO2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. K(1) is bonded to six equivalent O(1) atoms to form distorted KO6 octahedra that share corners with six equivalent Er(1)O6 octahedra, edges with six equivalent K(1)O6 octahedra, and edges with six equivalent Er(1)O6 octahedra. The corner-sharing octahedral tilt angles are 15°. Er(1) is bonded to six equivalent O(1) atoms to form ErO6 octahedra that share corners with six equivalent K(1)O6 octahedra, edges with six equivalent K(1)O6 octahedra, and edges with six equivalent Er(1)O6 octahedra. The corner-sharing octahedral tilt angles are 15°. O(1) is bonded to three equivalent K(1) and three equivalent Er(1) atoms to form a mixture of distorted corner and edge-sharing OK3Er3 octahedra. The corner-sharing octahedra are not tilted.
KErO2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. K(1) is bonded to six equivalent O(1) atoms to form distorted KO6 octahedra that share corners with six equivalent Er(1)O6 octahedra, edges with six equivalent K(1)O6 octahedra, and edges with six equivalent Er(1)O6 octahedra. The corner-sharing octahedral tilt angles are 15°. All K(1)-O(1) bond lengths are 2.77 Å. Er(1) is bonded to six equivalent O(1) atoms to form ErO6 octahedra that share corners with six equivalent K(1)O6 octahedra, edges with six equivalent K(1)O6 octahedra, and edges with six equivalent Er(1)O6 octahedra. The corner-sharing octahedral tilt angles are 15°. All Er(1)-O(1) bond lengths are 2.27 Å. O(1) is bonded to three equivalent K(1) and three equivalent Er(1) atoms to form a mixture of distorted corner and edge-sharing OK3Er3 octahedra. The corner-sharing octahedra are not tilted.