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DOE OSTI · 1666993

Materials Data on K4Co(MoO4)3 by Materials Project

Abstract

K4Co(MoO4)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are five inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six O2- atoms to form KO6 octahedra that share corners with two equivalent KO6 octahedra and corners with six MoO4 tetrahedra. The corner-sharing octahedral tilt angles are 74°. There are a spread of K–O bond distances ranging from 2.75–2.96 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.66–2.89 Å. In the third K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.75–3.42 Å. In the fourth K1+ site, K1+ is bonded to six O2- atoms to form KO6 octahedra that share a cornercorner with one KO6 octahedra, corners with six MoO4 tetrahedra, and an edgeedge with one KO6 octahedra. The corner-sharing octahedral tilt angles are 74°. There are a spread of K–O bond distances ranging from 2.67–2.84 Å. In the fifth K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.80–3.07 Å. There are three inequivalent Mo6+ sites. In the first Mo6+ site, Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with three KO6 octahedra and corners with two equivalent CoO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 45–62°. There is two shorter (1.78 Å) and two longer (1.83 Å) Mo–O bond length. In the second Mo6+ site, Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with four KO6 octahedra and a cornercorner with one CoO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 33–56°. There are a spread of Mo–O bond distances ranging from 1.78–1.83 Å. In the third Mo6+ site, Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with two KO6 octahedra and corners with two equivalent CoO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 51–55°. There are a spread of Mo–O bond distances ranging from 1.79–1.82 Å. Co2+ is bonded to five O2- atoms to form CoO5 trigonal bipyramids that share corners with five MoO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.96–2.35 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two K1+ and one Mo6+ atom. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three K1+ and one Mo6+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Mo6+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent K1+, one Mo6+, and one Co2+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Mo6+, and one Co2+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to three K1+ and one Mo6+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to three K1+ and one Mo6+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Mo6+, and one Co2+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Mo6+ and one Co2+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to three K1+ and one Mo6+ atom. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three K1+ and one Mo6+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one Mo6+, and one Co2+ atom.

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2020-07-15. Materials Data on K4Co(MoO4)3 by Materials Project. https://doi.org/10.17188/1666993

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