Materials Data on CaCd3O4 by Materials Project

Abstract

CaCd3O4 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with two equivalent CdO6 octahedra, corners with four equivalent CaO6 octahedra, edges with four equivalent CaO6 octahedra, and edges with eight equivalent CdO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.39 Å) and four longer (2.40 Å) Ca–O bond lengths. There are two inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with six equivalent CdO6 octahedra, edges with four equivalent CaO6 octahedra, and edges with eight CdO6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Cd–O bond distances ranging from 2.36–2.41 Å. In the second Cd2+ site, Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four equivalent CdO6 octahedra, and edges with twelve CdO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.38 Å) and four longer (2.40 Å) Cd–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to one Ca2+ and five Cd2+ atoms to form a mixture of corner and edge-sharing OCaCd5 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second O2- site, O2- is bonded to four equivalent Ca2+ and two equivalent Cd2+ atoms to form OCa4Cd2 octahedra that share corners with six OCa4Cd2 octahedra and edges with twelve OCaCd5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third O2- site, O2- is bonded to six Cd2+ atoms to form OCd6 octahedra that share corners with six OCa4Cd2 octahedra and edges with twelve OCaCd5 octahedra. The corner-sharing octahedral tilt angles are 0°.