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DOE OSTI · 1276900

Materials Data on Ca21(Mn2Bi9)2 by Materials Project

Abstract

Ca21Mn4Bi18 is Magnesium tetraboride-derived structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are eleven inequivalent Ca sites. In the first Ca site, Ca is bonded in a 5-coordinate geometry to five Bi atoms. There are a spread of Ca–Bi bond distances ranging from 3.14–3.59 Å. In the second Ca site, Ca is bonded in a 6-coordinate geometry to six Bi atoms. There are a spread of Ca–Bi bond distances ranging from 3.15–3.43 Å. In the third Ca site, Ca is bonded in a 8-coordinate geometry to one Mn and seven Bi atoms. The Ca–Mn bond length is 3.39 Å. There are a spread of Ca–Bi bond distances ranging from 3.13–3.71 Å. In the fourth Ca site, Ca is bonded in a 6-coordinate geometry to six Bi atoms. There are a spread of Ca–Bi bond distances ranging from 3.15–3.52 Å. In the fifth Ca site, Ca is bonded in a 9-coordinate geometry to two Mn and seven Bi atoms. There are one shorter (3.46 Å) and one longer (3.47 Å) Ca–Mn bond lengths. There are a spread of Ca–Bi bond distances ranging from 3.26–3.71 Å. In the sixth Ca site, Ca is bonded in a 6-coordinate geometry to six Bi atoms. There are a spread of Ca–Bi bond distances ranging from 3.12–3.50 Å. In the seventh Ca site, Ca is bonded to six Bi atoms to form distorted edge-sharing CaBi6 octahedra. There are a spread of Ca–Bi bond distances ranging from 3.20–3.46 Å. In the eighth Ca site, Ca is bonded in a 6-coordinate geometry to six Bi atoms. There are a spread of Ca–Bi bond distances ranging from 3.12–3.62 Å. In the ninth Ca site, Ca is bonded in a 6-coordinate geometry to six Bi atoms. There are a spread of Ca–Bi bond distances ranging from 3.14–3.77 Å. In the tenth Ca site, Ca is bonded in a 5-coordinate geometry to five Bi atoms. There are a spread of Ca–Bi bond distances ranging from 3.17–3.46 Å. In the eleventh Ca site, Ca is bonded in a 6-coordinate geometry to six Bi atoms. There are a spread of Ca–Bi bond distances ranging from 3.24–3.59 Å. There are four inequivalent Mn sites. In the first Mn site, Mn is bonded in a 4-coordinate geometry to two equivalent Ca and four Bi atoms. All Mn–Bi bond lengths are 2.87 Å. In the second Mn site, Mn is bonded in a 4-coordinate geometry to four Bi atoms. There are two shorter (2.87 Å) and two longer (2.90 Å) Mn–Bi bond lengths. In the third Mn site, Mn is bonded in a 4-coordinate geometry to two equivalent Ca and four Bi atoms. There are two shorter (2.83 Å) and two longer (2.96 Å) Mn–Bi bond lengths. In the fourth Mn site, Mn is bonded in a 4-coordinate geometry to two equivalent Ca and four Bi atoms. There are two shorter (2.85 Å) and two longer (2.96 Å) Mn–Bi bond lengths. There are nine inequivalent Bi sites. In the first Bi site, Bi is bonded in a 8-coordinate geometry to eight Ca atoms. In the second Bi site, Bi is bonded in a 2-coordinate geometry to eight Ca and one Bi atom. The Bi–Bi bond length is 3.11 Å. In the third Bi site, Bi is bonded in a 7-coordinate geometry to five Ca and two Mn atoms. In the fourth Bi site, Bi is bonded in a 9-coordinate geometry to eight Ca and one Mn atom. In the fifth Bi site, Bi is bonded in a 8-coordinate geometry to six Ca and two Mn atoms. In the sixth Bi site, Bi is bonded in a 10-coordinate geometry to eight Ca and two Bi atoms. There are one shorter (3.13 Å) and one longer (3.48 Å) Bi–Bi bond lengths. In the seventh Bi site, Bi is bonded in a 7-coordinate geometry to seven Ca atoms. In the eighth Bi site, Bi is bonded in a 7-coordinate geometry to six Ca and one Mn atom. In the ninth Bi site, Bi is bonded in a 10-coordinate geometry to seven Ca, two Mn, and one Bi atom.

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2020-04-29. Materials Data on Ca21(Mn2Bi9)2 by Materials Project. https://doi.org/10.17188/1276900

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36 MATERIALS SCIENCE↗