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Materials Data on K4Ca(WO4)3 by Materials Project

K4Ca(WO4)3 is (Cubic) Perovskite-derived structured and crystallizes in the cubic Im-3m space group. The structure is three-dimensional. K1+ is bonded to twelve O2- atoms to form KO12 cuboctahedra that share corners with twelve equivalent KO12 cuboctahedra, faces with six equivalent KO12 cuboctahedra, faces with two equivalent CaO6 octahedra, and faces with six equivalent WO6 octahedra. There are six shorter (2.90 Å) and six longer (2.91 Å) K–O bond lengths. Ca2+ is bonded to six equivalent O2- atoms to form CaO6 octahedra that share corners with six equivalent WO6 octahedra and faces with eight equivalent KO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Ca–O bond lengths are 2.25 Å. W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four equivalent WO6 octahedra, and faces with eight equivalent KO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There is two shorter (1.85 Å) and four longer (2.05 Å) W–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent K1+ and two equivalent W6+ atoms to form a mixture of distorted face and corner-sharing OK4W2 octahedra. The corner-sharing octahedra tilt angles range from 0–60°. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent K1+, one Ca2+, and one W6+ atom.

36 MATERIALS SCIENCE↗