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DOE OSTI · 1708481

Materials Data on Dy2Mn17C3 by Materials Project

Abstract

Dy2Mn17C3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Dy sites. In the first Dy site, Dy is bonded in a trigonal planar geometry to eight Mn and three equivalent C atoms. There are two shorter (3.01 Å) and six longer (3.23 Å) Dy–Mn bond lengths. All Dy–C bond lengths are 2.51 Å. In the second Dy site, Dy is bonded in a trigonal planar geometry to eight Mn and three equivalent C atoms. There are two shorter (3.01 Å) and six longer (3.23 Å) Dy–Mn bond lengths. All Dy–C bond lengths are 2.51 Å. In the third Dy site, Dy is bonded in a trigonal planar geometry to three equivalent C atoms. All Dy–C bond lengths are 2.43 Å. There are four inequivalent Mn sites. In the first Mn site, Mn is bonded to two Dy and ten Mn atoms to form distorted MnDy2Mn10 cuboctahedra that share corners with four equivalent MnDy2Mn10 cuboctahedra, corners with two equivalent CDy2Mn4 octahedra, faces with six equivalent MnDy2Mn10 cuboctahedra, and faces with four equivalent CDy2Mn4 octahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Mn–Mn bond distances ranging from 2.43–2.63 Å. In the second Mn site, Mn is bonded in a single-bond geometry to four Mn and one C atom. Both Mn–Mn bond lengths are 2.65 Å. The Mn–C bond length is 1.90 Å. In the third Mn site, Mn is bonded in a 2-coordinate geometry to one Dy and thirteen Mn atoms. There are one shorter (2.31 Å) and three longer (2.63 Å) Mn–Mn bond lengths. In the fourth Mn site, Mn is bonded in a single-bond geometry to three Mn and one C atom. The Mn–C bond length is 1.89 Å. C is bonded to two Dy and four Mn atoms to form CDy2Mn4 octahedra that share corners with two equivalent MnDy2Mn10 cuboctahedra, corners with four equivalent CDy2Mn4 octahedra, and faces with four equivalent MnDy2Mn10 cuboctahedra. The corner-sharing octahedral tilt angles are 60°.

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2019-01-12. Materials Data on Dy2Mn17C3 by Materials Project. https://doi.org/10.17188/1708481

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36 MATERIALS SCIENCE↗