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DOE OSTI · 1723834

Materials Data on Nb13Co40Si31 by Materials Project

Abstract

Nb13Co40Si31 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. there are four inequivalent Nb sites. In the first Nb site, Nb is bonded in a 11-coordinate geometry to one Nb, nine Co, and seven Si atoms. The Nb–Nb bond length is 3.18 Å. There are a spread of Nb–Co bond distances ranging from 2.63–2.96 Å. There are a spread of Nb–Si bond distances ranging from 2.70–3.06 Å. In the second Nb site, Nb is bonded in a 7-coordinate geometry to ten Co and seven Si atoms. There are a spread of Nb–Co bond distances ranging from 2.68–2.91 Å. There are a spread of Nb–Si bond distances ranging from 2.64–2.96 Å. In the third Nb site, Nb is bonded in a 3-coordinate geometry to nine Co and six Si atoms. There are a spread of Nb–Co bond distances ranging from 2.66–2.80 Å. There are two shorter (2.68 Å) and four longer (2.76 Å) Nb–Si bond lengths. In the fourth Nb site, Nb is bonded in a distorted hexagonal planar geometry to six equivalent Co atoms. All Nb–Co bond lengths are 2.66 Å. There are eight inequivalent Co sites. In the first Co site, Co is bonded in a 6-coordinate geometry to four Nb, four equivalent Co, and four Si atoms. All Co–Co bond lengths are 2.66 Å. There are two shorter (2.27 Å) and two longer (2.34 Å) Co–Si bond lengths. In the second Co site, Co is bonded in a 9-coordinate geometry to three equivalent Nb and six equivalent Si atoms. All Co–Si bond lengths are 2.33 Å. In the third Co site, Co is bonded to three Nb, three Co, and six Si atoms to form a mixture of distorted corner, edge, and face-sharing CoNb3Co3Si6 cuboctahedra. There are one shorter (2.48 Å) and two longer (2.52 Å) Co–Co bond lengths. There are a spread of Co–Si bond distances ranging from 2.37–2.60 Å. In the fourth Co site, Co is bonded in a 11-coordinate geometry to three Nb, four Co, and four Si atoms. There are a spread of Co–Co bond distances ranging from 2.54–2.69 Å. There are a spread of Co–Si bond distances ranging from 2.27–2.38 Å. In the fifth Co site, Co is bonded to four equivalent Nb, two equivalent Co, and six Si atoms to form distorted face-sharing CoNb4Co2Si6 cuboctahedra. Both Co–Co bond lengths are 2.56 Å. There are a spread of Co–Si bond distances ranging from 2.30–2.40 Å. In the sixth Co site, Co is bonded in a 12-coordinate geometry to three Nb, four Co, and five Si atoms. The Co–Co bond length is 2.57 Å. There are a spread of Co–Si bond distances ranging from 2.32–2.45 Å. In the seventh Co site, Co is bonded in a 6-coordinate geometry to four equivalent Co and six Si atoms. There are a spread of Co–Si bond distances ranging from 2.29–2.44 Å. In the eighth Co site, Co is bonded in a 11-coordinate geometry to three Nb, three Co, and five Si atoms. Both Co–Co bond lengths are 2.64 Å. There are a spread of Co–Si bond distances ranging from 2.38–2.67 Å. There are eight inequivalent Si sites. In the first Si site, Si is bonded in a 12-coordinate geometry to two equivalent Nb and eight Co atoms. In the second Si site, Si is bonded in a 9-coordinate geometry to three Nb and six Co atoms. In the third Si site, Si is bonded in a distorted q6 geometry to three equivalent Nb and six equivalent Co atoms. In the fourth Si site, Si is bonded in a body-centered cubic geometry to two equivalent Nb and eight Co atoms. In the fifth Si site, Si is bonded in a 12-coordinate geometry to three Nb, six Co, and three Si atoms. There are two shorter (2.59 Å) and one longer (2.64 Å) Si–Si bond lengths. In the sixth Si site, Si is bonded in a 10-coordinate geometry to two equivalent Nb, six Co, and two equivalent Si atoms. Both Si–Si bond lengths are 2.49 Å. In the seventh Si site, Si is bonded in a 6-coordinate geometry to two equivalent Nb and six Co atoms. In the eighth Si site, Si is bonded in a 12-coordinate geometry to three Nb, seven Co, and two equivalent Si atoms.

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2020-05-02. Materials Data on Nb13Co40Si31 by Materials Project. https://doi.org/10.17188/1723834

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