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DOE OSTI · 1284214

Materials Data on Mn17Nb31N48 by Materials Project

Abstract

Nb31Mn17N48 is Caswellsilverite-like structured and crystallizes in the trigonal P312 space group. The structure is three-dimensional. there are nine inequivalent Nb sites. In the first Nb site, Nb is bonded to six N atoms to form distorted NbN6 pentagonal pyramids that share corners with two NbN6 octahedra, corners with four MnN6 octahedra, edges with two NbN6 octahedra, edges with four MnN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 2–3°. There are a spread of Nb–N bond distances ranging from 2.20–2.23 Å. In the second Nb site, Nb is bonded to six N atoms to form distorted NbN6 pentagonal pyramids that share a cornercorner with one NbN6 octahedra, corners with five MnN6 octahedra, an edgeedge with one NbN6 octahedra, edges with five MnN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Nb–N bond distances ranging from 2.18–2.23 Å. In the third Nb site, Nb is bonded to six N atoms to form distorted NbN6 pentagonal pyramids that share corners with two NbN6 octahedra, corners with four MnN6 octahedra, edges with two NbN6 octahedra, edges with four MnN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Nb–N bond distances ranging from 2.19–2.25 Å. In the fourth Nb site, Nb is bonded to six N atoms to form distorted NbN6 pentagonal pyramids that share corners with two NbN6 octahedra, corners with four MnN6 octahedra, edges with two NbN6 octahedra, edges with four MnN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 2–3°. There are a spread of Nb–N bond distances ranging from 2.20–2.22 Å. In the fifth Nb site, Nb is bonded to six N atoms to form NbN6 octahedra that share corners with six NbN6 pentagonal pyramids, edges with six MnN6 octahedra, and edges with six NbN6 pentagonal pyramids. There are three shorter (2.15 Å) and three longer (2.16 Å) Nb–N bond lengths. In the sixth Nb site, Nb is bonded to six equivalent N atoms to form NbN6 octahedra that share corners with six equivalent NbN6 pentagonal pyramids, edges with three equivalent NbN6 octahedra, edges with three equivalent MnN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. All Nb–N bond lengths are 2.18 Å. In the seventh Nb site, Nb is bonded to six equivalent N atoms to form NbN6 octahedra that share corners with six equivalent NbN6 pentagonal pyramids, edges with six MnN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. All Nb–N bond lengths are 2.16 Å. In the eighth Nb site, Nb is bonded to six N atoms to form NbN6 octahedra that share corners with six NbN6 pentagonal pyramids, edges with six MnN6 octahedra, and edges with six NbN6 pentagonal pyramids. There are three shorter (2.15 Å) and three longer (2.17 Å) Nb–N bond lengths. In the ninth Nb site, Nb is bonded to six equivalent N atoms to form NbN6 octahedra that share corners with six equivalent NbN6 pentagonal pyramids, edges with three equivalent NbN6 octahedra, edges with three equivalent MnN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. All Nb–N bond lengths are 2.18 Å. There are ten inequivalent Mn sites. In the first Mn site, Mn is bonded to six equivalent N atoms to form MnN6 octahedra that share corners with six equivalent NbN6 pentagonal pyramids, edges with three equivalent NbN6 octahedra, edges with three equivalent MnN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. All Mn–N bond lengths are 2.17 Å. In the second Mn site, Mn is bonded to six N atoms to form MnN6 octahedra that share corners with six NbN6 pentagonal pyramids, edges with three equivalent NbN6 octahedra, edges with three equivalent MnN6 octahedra, and edges with six NbN6 pentagonal pyramids. There are three shorter (2.14 Å) and three longer (2.17 Å) Mn–N bond lengths. In the third Mn site, Mn is bonded to six N atoms to form MnN6 octahedra that share corners with six NbN6 pentagonal pyramids, edges with three equivalent NbN6 octahedra, edges with three equivalent MnN6 octahedra, and edges with six NbN6 pentagonal pyramids. There are three shorter (2.14 Å) and three longer (2.16 Å) Mn–N bond lengths. In the fourth Mn site, Mn is bonded to six equivalent N atoms to form MnN6 octahedra that share corners with six equivalent NbN6 pentagonal pyramids, edges with three equivalent NbN6 octahedra, edges with three equivalent MnN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. All Mn–N bond lengths are 2.15 Å. In the fifth Mn site, Mn is bonded to six N atoms to form MnN6 octahedra that share corners with six NbN6 pentagonal pyramids, edges with three equivalent NbN6 octahedra, edges with three equivalent MnN6 octahedra, and edges with six NbN6 pentagonal pyramids. There are three shorter (2.15 Å) and three longer (2.16 Å) Mn–N bond lengths. In the sixth Mn site, Mn is bonded to six N atoms to form MnN6 octahedra that share corners with six NbN6 pentagonal pyramids, edges with six MnN6 octahedra, and edges with six NbN6 pentagonal pyramids. There are three shorter (2.11 Å) and three longer (2.14 Å) Mn–N bond lengths. In the seventh Mn site, Mn is bonded to six N atoms to form MnN6 octahedra that share corners with six NbN6 pentagonal pyramids, edges with six MnN6 octahedra, and edges with six NbN6 pentagonal pyramids. There are three shorter (2.15 Å) and three longer (2.17 Å) Mn–N bond lengths. In the eighth Mn site, Mn is bonded to six N atoms to form MnN6 octahedra that share corners with six NbN6 pentagonal pyramids, edges with three equivalent NbN6 octahedra, edges with three equivalent MnN6 octahedra, and edges with six NbN6 pentagonal pyramids. There are three shorter (2.13 Å) and three longer (2.14 Å) Mn–N bond lengths. In the ninth Mn site, Mn is bonded to six equivalent N atoms to form MnN6 octahedra that share corners with six equivalent NbN6 pentagonal pyramids, edges with six NbN6 octahedra, and edges with six equivalent NbN6 pentagonal pyramids. All Mn–N bond lengths are 2.15 Å. In the tenth Mn site, Mn is bonded to six N atoms to form MnN6 octahedra that share corners with six NbN6 pentagonal pyramids, edges with six MnN6 octahedra, and edges with six NbN6 pentagonal pyramids. There are three shorter (2.10 Å) and three longer (2.13 Å) Mn–N bond lengths. There are eight inequivalent N sites. In the first N site, N is bonded to four Nb and two Mn atoms to form a mixture of edge, face, and corner-sharing NMn2Nb4 octahedra. The corner-sharing octahedra tilt angles range from 0–48°. In the second N site, N is bonded to three equivalent Nb and three Mn atoms to form NMn3Nb3 octahedra that share corners with nine NMnNb5 octahedra, edges with nine NMn3Nb3 octahedra, and a faceface with one NMnNb5 octahedra. The corner-sharing octahedra tilt angles range from 1–49°. In the third N site, N is bonded to four Nb and two Mn atoms to form a mixture of edge, face, and corner-sharing NMn2Nb4 octahedra. The corner-sharing octahedra tilt angles range from 0–48°. In the fourth N site, N is bonded to four Nb and two Mn atoms to form a mixture of edge, face, and corner-sharing NMn2Nb4 octahedra. The corner-sharing octahedra tilt angles range from 0–48°. In the fifth N site, N is bonded to four Nb and two Mn atoms to form a mixture of edge, face, and corner-sharing NMn2Nb4 octahedra. The corner-sharing octahedra tilt angles range from 0–48°. In the sixth N site, N is bonded to five Nb and one Mn atom to form NMnNb5 octahedra that share corners with nine NMn3Nb3 octahedra, edges with nine equivalent NMnNb5 octahedra, and a faceface with one NMn3Nb3 octahedra. The corner-sharing octahedra tilt angles range from 0–49°. In the seventh N site, N is bonded to three equivalent Nb and three Mn atoms to form NMn3Nb3 octahedra that share corners with nine NMn3Nb3 octahedra, edges with nine NMn3Nb3 octahedra, and a faceface with one NMn2Nb4 octahedra. The corner-sharing octahedra tilt angles range from 1–49°. In the eighth N site, N is bonded to four Nb and two Mn atoms to form NMn2Nb4 octahedra that share corners with nine NMn2Nb4 octahedra, edges with nine NMn2Nb4 octahedra, and a faceface with one NMn3Nb3 octahedra. The corner-sharing octahedra tilt angles range from 0–49°.

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2020-04-30. Materials Data on Mn17Nb31N48 by Materials Project. https://doi.org/10.17188/1284214

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