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DOE OSTI · 1724812

Materials Data on NbVCo6 by Materials Project

Abstract

NbVCo6 is beta Cu3Ti-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three inequivalent Nb sites. In the first Nb site, Nb is bonded to twelve Co atoms to form NbCo12 cuboctahedra that share corners with three equivalent VCo12 cuboctahedra, corners with six equivalent NbCo12 cuboctahedra, corners with six equivalent CoNb2V2Co8 cuboctahedra, edges with twenty-one CoNbV3Co8 cuboctahedra, faces with three equivalent NbCo12 cuboctahedra, faces with four VCo12 cuboctahedra, and faces with twelve CoNb3VCo8 cuboctahedra. There are nine shorter (2.56 Å) and three longer (2.64 Å) Nb–Co bond lengths. In the second Nb site, Nb is bonded to twelve Co atoms to form NbCo12 cuboctahedra that share corners with six equivalent CoNbV3Co8 cuboctahedra, corners with nine NbCo12 cuboctahedra, edges with twenty-one CoNb3VCo8 cuboctahedra, faces with seven VCo12 cuboctahedra, and faces with twelve CoNbV3Co8 cuboctahedra. There are a spread of Nb–Co bond distances ranging from 2.53–2.60 Å. In the third Nb site, Nb is bonded to twelve Co atoms to form NbCo12 cuboctahedra that share corners with six equivalent CoNbV3Co8 cuboctahedra, corners with nine NbCo12 cuboctahedra, edges with twenty-one CoNb3VCo8 cuboctahedra, faces with three equivalent NbCo12 cuboctahedra, faces with four VCo12 cuboctahedra, and faces with twelve CoNb3VCo8 cuboctahedra. There are a spread of Nb–Co bond distances ranging from 2.55–2.62 Å. There are three inequivalent V sites. In the first V site, V is bonded to twelve Co atoms to form VCo12 cuboctahedra that share corners with three equivalent NbCo12 cuboctahedra, corners with six equivalent VCo12 cuboctahedra, corners with six equivalent CoNb2V2Co8 cuboctahedra, edges with twenty-one CoNbV3Co8 cuboctahedra, faces with three equivalent NbCo12 cuboctahedra, faces with four VCo12 cuboctahedra, and faces with twelve CoNbV3Co8 cuboctahedra. There are a spread of V–Co bond distances ranging from 2.47–2.56 Å. In the second V site, V is bonded to twelve Co atoms to form VCo12 cuboctahedra that share corners with six equivalent VCo12 cuboctahedra, corners with twelve CoNb2V2Co8 cuboctahedra, edges with eighteen CoNbV3Co8 cuboctahedra, faces with three equivalent VCo12 cuboctahedra, faces with five NbCo12 cuboctahedra, and faces with twelve CoNbV3Co8 cuboctahedra. There are a spread of V–Co bond distances ranging from 2.51–2.55 Å. In the third V site, V is bonded to twelve Co atoms to form VCo12 cuboctahedra that share corners with six equivalent VCo12 cuboctahedra, corners with twelve CoNbV3Co8 cuboctahedra, edges with eighteen CoNb2V2Co8 cuboctahedra, a faceface with one VCo12 cuboctahedra, faces with seven NbCo12 cuboctahedra, and faces with twelve CoNb3VCo8 cuboctahedra. There are three shorter (2.53 Å) and nine longer (2.55 Å) V–Co bond lengths. There are eleven inequivalent Co sites. In the first Co site, Co is bonded to two equivalent Nb, two V, and eight Co atoms to form distorted CoNb2V2Co8 cuboctahedra that share corners with two equivalent VCo12 cuboctahedra, corners with thirteen CoNb2V2Co8 cuboctahedra, edges with three NbCo12 cuboctahedra, edges with four VCo12 cuboctahedra, edges with fourteen CoNb3VCo8 cuboctahedra, faces with two equivalent NbCo12 cuboctahedra, faces with two VCo12 cuboctahedra, and faces with fifteen CoNbV3Co8 cuboctahedra. Both Co–Nb bond lengths are 2.55 Å. There are one shorter (2.47 Å) and one longer (2.55 Å) Co–V bond lengths. There are a spread of Co–Co bond distances ranging from 2.48–2.62 Å. In the second Co site, Co is bonded to three Nb, one V, and eight Co atoms to form distorted CoNb3VCo8 cuboctahedra that share corners with two equivalent VCo12 cuboctahedra, corners with thirteen CoNb2V2Co8 cuboctahedra, edges with two equivalent VCo12 cuboctahedra, edges with five NbCo12 cuboctahedra, edges with fourteen CoNb3VCo8 cuboctahedra, a faceface with one VCo12 cuboctahedra, faces with three NbCo12 cuboctahedra, and faces with fifteen CoNb3VCo8 cuboctahedra. All Co–Nb bond lengths are 2.56 Å. The Co–V bond length is 2.53 Å. There are a spread of Co–Co bond distances ranging from 2.45–2.65 Å. In the third Co site, Co is bonded to one Nb, three V, and eight Co atoms to form distorted CoNbV3Co8 cuboctahedra that share corners with two equivalent VCo12 cuboctahedra, corners with thirteen CoNb3VCo8 cuboctahedra, edges with three NbCo12 cuboctahedra, edges with four VCo12 cuboctahedra, edges with fourteen CoNbV3Co8 cuboctahedra, a faceface with one NbCo12 cuboctahedra, faces with three VCo12 cuboctahedra, and faces with fifteen CoNbV3Co8 cuboctahedra. The Co–Nb bond length is 2.53 Å. Both Co–V bond lengths are 2.56 Å. There are a spread of Co–Co bond distances ranging from 2.44–2.65 Å. In the fourth Co site, Co is bonded to three Nb, one V, and eight Co atoms to form distorted CoNb3VCo8 cuboctahedra that share corners with two equivalent VCo12 cuboctahedra, corners with thirteen CoNb2V2Co8 cuboctahedra, edges with two equivalent VCo12 cuboctahedra, edges with five NbCo12 cuboctahedra, edges with fourteen CoNb3VCo8 cuboctahedra, a faceface with one VCo12 cuboctahedra, faces with three NbCo12 cuboctahedra, and faces with fifteen CoNb3VCo8 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.45–2.65 Å. In the fifth Co site, Co is bonded to one Nb, three V, and eight Co atoms to form distorted CoNbV3Co8 cuboctahedra that share corners with two equivalent VCo12 cuboctahedra, corners with thirteen CoNb3VCo8 cuboctahedra, edges with three NbCo12 cuboctahedra, edges with four VCo12 cuboctahedra, edges with fourteen CoNbV3Co8 cuboctahedra, a faceface with one NbCo12 cuboctahedra, faces with three VCo12 cuboctahedra, and faces with fifteen CoNbV3Co8 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.44–2.65 Å. In the sixth Co site, Co is bonded to one Nb, three V, and eight Co atoms to form distorted CoNbV3Co8 cuboctahedra that share corners with two equivalent VCo12 cuboctahedra, corners with thirteen CoNb3VCo8 cuboctahedra, edges with three NbCo12 cuboctahedra, edges with four VCo12 cuboctahedra, edges with fourteen CoNbV3Co8 cuboctahedra, a faceface with one NbCo12 cuboctahedra, faces with three VCo12 cuboctahedra, and faces with fifteen CoNbV3Co8 cuboctahedra. The Co–V bond length is 2.53 Å. There are two shorter (2.44 Å) and two longer (2.54 Å) Co–Co bond lengths. In the seventh Co site, Co is bonded to three Nb, one V, and eight Co atoms to form distorted CoNb3VCo8 cuboctahedra that share corners with two equivalent VCo12 cuboctahedra, corners with thirteen CoNb3VCo8 cuboctahedra, edges with three VCo12 cuboctahedra, edges with four NbCo12 cuboctahedra, edges with fourteen CoNb3VCo8 cuboctahedra, a faceface with one VCo12 cuboctahedra, faces with three NbCo12 cuboctahedra, and faces with fifteen CoNb3VCo8 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.44–2.66 Å. In the eighth Co site, Co is bonded to two equivalent Nb, two V, and eight Co atoms to form distorted CoNb2V2Co8 cuboctahedra that share corners with two equivalent VCo12 cuboctahedra, corners with thirteen CoNb2V2Co8 cuboctahedra, edges with three NbCo12 cuboctahedra, edges with four VCo12 cuboctahedra, edges with fourteen CoNb3VCo8 cuboctahedra, faces with two equivalent NbCo12 cuboctahedra, faces with two VCo12 cuboctahedra, and faces with fifteen CoNbV3Co8 cuboctahedra. There are a spread of Co–Co bond distances ranging from 2.48–2.62 Å. In the ninth Co site, Co is bonded to three Nb, one V, and eight Co atoms to form distorted CoNb3VCo8 cuboctahedra that share corners with two equivalent VCo12 cuboctahedra, corners with thirteen CoNb3VCo8 cuboctahedra, edges with three VCo12 cuboctahedra, edges with four NbCo12 cuboctahedra, edges with fourteen CoNbV3Co8 cuboctahedra, a faceface with one VCo12 cuboctahedra, faces with three NbCo12 cuboctahedra, and faces with fifteen CoNb3VCo8 cuboctahedra. Both Co–Co bond lengths are 2.49 Å. In the tenth Co site, Co is bonded to two Nb, two equivalent V, and eight Co atoms to form CoNb2V2Co8 cuboctahedra that share corners with two equivalent NbCo12 cuboctahedra, corners with two equivalent VCo12 cuboctahedra, corners with fourteen CoNbV3Co8 cuboctahedra, edges with two equivalent VCo12 cuboctahedra, edges with four NbCo12 cuboctahedra, edges with twelve CoNb3VCo8 cuboctahedra, faces with two NbCo12 cuboctahedra, faces with two equivalent VCo12 cuboctahedra, and faces with sixteen CoNb3VCo8 cuboctahedra. There are two shorter (2.53 Å) and two longer (2.57 Å) Co–Co bond lengths. In the eleventh Co site, Co is bonded to one Nb, three V, and eight Co atoms to form CoNbV3Co8 cuboctahedra that share corners with four NbCo12 cuboctahedra, corners with fourteen CoNb3VCo8 cuboctahedra, edges with two equivalent NbCo12 cuboctahedra, edges with four VCo12 cuboctahedra, edges with twelve CoNbV3Co8 cuboctahedra, a faceface with one NbCo12 cuboctahedra, faces with three VCo12 cuboctahedra, and faces with sixteen CoNb3VCo8 cuboctahedra. There are two shorter (2.51 Å) and two longer (2.60 Å) Co–Co bond lengths.

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2020-04-30. Materials Data on NbVCo6 by Materials Project. https://doi.org/10.17188/1724812

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