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DOE OSTI · 1679324

Materials Data on NbVCo by Materials Project

Abstract

NbVCo is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are six inequivalent Nb sites. In the first Nb site, Nb is bonded in a 7-coordinate geometry to four Nb, five V, and seven Co atoms. There are a spread of Nb–Nb bond distances ranging from 2.93–3.01 Å. There are three shorter (2.89 Å) and two longer (2.93 Å) Nb–V bond lengths. There are a spread of Nb–Co bond distances ranging from 2.78–2.90 Å. In the second Nb site, Nb is bonded in a 5-coordinate geometry to four Nb, seven V, and five Co atoms. There are two shorter (3.01 Å) and one longer (3.18 Å) Nb–Nb bond lengths. There are a spread of Nb–V bond distances ranging from 2.86–2.94 Å. There are two shorter (2.81 Å) and three longer (2.86 Å) Nb–Co bond lengths. In the third Nb site, Nb is bonded in a 5-coordinate geometry to four Nb, seven V, and five Co atoms. There are one shorter (2.93 Å) and two longer (3.01 Å) Nb–Nb bond lengths. There are a spread of Nb–V bond distances ranging from 2.86–2.94 Å. There are two shorter (2.81 Å) and three longer (2.86 Å) Nb–Co bond lengths. In the fourth Nb site, Nb is bonded in a 7-coordinate geometry to four Nb, five V, and seven Co atoms. There are one shorter (2.93 Å) and one longer (2.98 Å) Nb–Nb bond lengths. There are three shorter (2.89 Å) and two longer (2.93 Å) Nb–V bond lengths. There are a spread of Nb–Co bond distances ranging from 2.78–2.90 Å. In the fifth Nb site, Nb is bonded in a 5-coordinate geometry to four Nb, seven V, and five Co atoms. The Nb–Nb bond length is 3.18 Å. There are a spread of Nb–V bond distances ranging from 2.86–2.94 Å. There are two shorter (2.81 Å) and three longer (2.86 Å) Nb–Co bond lengths. In the sixth Nb site, Nb is bonded in a 5-coordinate geometry to four Nb, seven V, and five Co atoms. There are one shorter (2.93 Å) and two longer (3.01 Å) Nb–Nb bond lengths. There are a spread of Nb–V bond distances ranging from 2.86–2.94 Å. There are two shorter (2.81 Å) and three longer (2.86 Å) Nb–Co bond lengths. There are three inequivalent V sites. In the first V site, V is bonded in a 12-coordinate geometry to six Nb and six Co atoms. There are a spread of V–Co bond distances ranging from 2.38–2.46 Å. In the second V site, V is bonded to six Nb, four V, and two equivalent Co atoms to form distorted VNb6V4Co2 cuboctahedra that share corners with four equivalent VNb6V4Co2 cuboctahedra, corners with ten CoNb6V4Co2 cuboctahedra, edges with two equivalent VNb6V4Co2 cuboctahedra, edges with four equivalent CoNb6V2Co4 cuboctahedra, faces with eight VNb6V4Co2 cuboctahedra, and faces with eight CoNb6V4Co2 cuboctahedra. There are a spread of V–V bond distances ranging from 2.37–2.48 Å. Both V–Co bond lengths are 2.54 Å. In the third V site, V is bonded to six Nb, four equivalent V, and two equivalent Co atoms to form distorted VNb6V4Co2 cuboctahedra that share corners with four equivalent VNb6V4Co2 cuboctahedra, corners with twelve CoNb6V4Co2 cuboctahedra, edges with two equivalent VNb6V4Co2 cuboctahedra, faces with eight equivalent VNb6V4Co2 cuboctahedra, and faces with ten CoNb6V4Co2 cuboctahedra. Both V–Co bond lengths are 2.53 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded to six Nb, four V, and two equivalent Co atoms to form distorted CoNb6V4Co2 cuboctahedra that share corners with four equivalent CoNb6V2Co4 cuboctahedra, corners with six VNb6V4Co2 cuboctahedra, edges with six equivalent CoNb6V4Co2 cuboctahedra, faces with eight CoNb6V4Co2 cuboctahedra, and faces with nine VNb6V4Co2 cuboctahedra. Both Co–Co bond lengths are 2.45 Å. In the second Co site, Co is bonded to six Nb, two equivalent V, and four Co atoms to form distorted CoNb6V2Co4 cuboctahedra that share corners with eight CoNb6V4Co2 cuboctahedra, corners with ten VNb6V4Co2 cuboctahedra, edges with two equivalent CoNb6V2Co4 cuboctahedra, edges with four equivalent VNb6V4Co2 cuboctahedra, faces with four VNb6V4Co2 cuboctahedra, and faces with ten CoNb6V4Co2 cuboctahedra. There are one shorter (2.45 Å) and one longer (2.50 Å) Co–Co bond lengths.

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2020-05-02. Materials Data on NbVCo by Materials Project. https://doi.org/10.17188/1679324

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