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DOE OSTI · 1676146

Materials Data on CsMg6Co by Materials Project

Abstract

CsMg6Co crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Cs is bonded to two equivalent Cs and ten Mg atoms to form distorted CsCs2Mg10 cuboctahedra that share corners with six equivalent CsCs2Mg10 cuboctahedra, edges with six equivalent MgMg6 pentagonal pyramids, and faces with two equivalent CsCs2Mg10 cuboctahedra. Both Cs–Cs bond lengths are 3.91 Å. There are a spread of Cs–Mg bond distances ranging from 3.69–4.10 Å. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a distorted single-bond geometry to two equivalent Cs, two equivalent Mg, and one Co atom. Both Mg–Mg bond lengths are 3.24 Å. The Mg–Co bond length is 2.73 Å. In the second Mg site, Mg is bonded in a distorted L-shaped geometry to two equivalent Cs, one Mg, and two equivalent Co atoms. The Mg–Mg bond length is 3.14 Å. Both Mg–Co bond lengths are 2.63 Å. In the third Mg site, Mg is bonded to six Mg atoms to form distorted MgMg6 pentagonal pyramids that share edges with six equivalent CsCs2Mg10 cuboctahedra and edges with two equivalent MgMg6 pentagonal pyramids. In the fourth Mg site, Mg is bonded in a distorted water-like geometry to two equivalent Cs and two equivalent Co atoms. Both Mg–Co bond lengths are 2.54 Å. Co is bonded in a 8-coordinate geometry to eight Mg atoms.

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2020-05-04. Materials Data on CsMg6Co by Materials Project. https://doi.org/10.17188/1676146

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