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DOE OSTI · 1745287

Materials Data on Ce2Mn17C2 by Materials Project

Abstract

Ce2Mn17C2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ce is bonded in a distorted bent 120 degrees geometry to nine Mn and two equivalent C atoms. There are a spread of Ce–Mn bond distances ranging from 2.91–3.38 Å. Both Ce–C bond lengths are 2.53 Å. There are seven inequivalent Mn sites. In the first Mn site, Mn is bonded in a 1-coordinate geometry to one Ce and thirteen Mn atoms. There are a spread of Mn–Mn bond distances ranging from 2.37–2.67 Å. In the second Mn site, Mn is bonded to two equivalent Ce and ten Mn atoms to form distorted MnCe2Mn10 cuboctahedra that share corners with eight MnCe2Mn10 cuboctahedra, corners with four equivalent CCe2Mn4 octahedra, edges with three MnCe2Mn10 cuboctahedra, edges with two equivalent CCe2Mn4 octahedra, and faces with nine MnCe2Mn10 cuboctahedra. The corner-sharing octahedra tilt angles range from 21–28°. There are a spread of Mn–Mn bond distances ranging from 2.37–2.66 Å. In the third Mn site, Mn is bonded in a single-bond geometry to six Mn and one C atom. There are two shorter (2.41 Å) and one longer (2.60 Å) Mn–Mn bond lengths. The Mn–C bond length is 1.90 Å. In the fourth Mn site, Mn is bonded in a single-bond geometry to five Mn and one C atom. There are two shorter (2.43 Å) and one longer (2.62 Å) Mn–Mn bond lengths. The Mn–C bond length is 1.88 Å. In the fifth Mn site, Mn is bonded to three equivalent Ce and nine Mn atoms to form distorted MnCe3Mn9 cuboctahedra that share corners with eleven MnCe2Mn10 cuboctahedra, corners with four equivalent CCe2Mn4 octahedra, edges with four MnCe3Mn9 cuboctahedra, faces with eight MnCe2Mn10 cuboctahedra, and faces with two equivalent CCe2Mn4 octahedra. The corner-sharing octahedra tilt angles range from 61–70°. Both Mn–Mn bond lengths are 2.46 Å. In the sixth Mn site, Mn is bonded to two equivalent Ce and ten Mn atoms to form distorted MnCe2Mn10 cuboctahedra that share corners with fourteen MnCe2Mn10 cuboctahedra, edges with two equivalent MnCe3Mn9 cuboctahedra, faces with ten MnCe2Mn10 cuboctahedra, and faces with four equivalent CCe2Mn4 octahedra. In the seventh Mn site, Mn is bonded to two equivalent Ce and ten Mn atoms to form distorted MnCe2Mn10 cuboctahedra that share corners with eight MnCe2Mn10 cuboctahedra, corners with two equivalent CCe2Mn4 octahedra, edges with four MnCe3Mn9 cuboctahedra, faces with eight MnCe2Mn10 cuboctahedra, and faces with two equivalent CCe2Mn4 octahedra. The corner-sharing octahedral tilt angles are 47°. C is bonded to two equivalent Ce and four Mn atoms to form CCe2Mn4 octahedra that share corners with ten MnCe2Mn10 cuboctahedra, corners with two equivalent CCe2Mn4 octahedra, edges with two equivalent MnCe2Mn10 cuboctahedra, and faces with six MnCe2Mn10 cuboctahedra. The corner-sharing octahedral tilt angles are 63°.

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2020-06-05. Materials Data on Ce2Mn17C2 by Materials Project. https://doi.org/10.17188/1745287

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