Materials Data on KErO2 by Materials Project
KErO2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. K1+ is bonded to six equivalent O2- atoms to form distorted KO6 octahedra that share corners with six equivalent ErO6 octahedra, edges with six equivalent KO6 octahedra, and edges with six equivalent ErO6 octahedra. The corner-sharing octahedral tilt angles are 15°. All K–O bond lengths are 2.81 Å. Er3+ is bonded to six equivalent O2- atoms to form ErO6 octahedra that share corners with six equivalent KO6 octahedra, edges with six equivalent KO6 octahedra, and edges with six equivalent ErO6 octahedra. The corner-sharing octahedral tilt angles are 15°. All Er–O bond lengths are 2.30 Å. O2- is bonded to three equivalent K1+ and three equivalent Er3+ atoms to form a mixture of distorted edge and corner-sharing OK3Er3 octahedra. The corner-sharing octahedral tilt angles are 0°.