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DOE OSTI · 1758469

Materials Data on Ce6Ni20As13 by Materials Project

Abstract

Ce6Ni20As13 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. there are two inequivalent Ce3+ sites. In the first Ce3+ site, Ce3+ is bonded to six As3- atoms to form distorted CeAs6 pentagonal pyramids that share corners with four equivalent CeAs6 pentagonal pyramids, corners with two equivalent NiAs5 square pyramids, corners with twelve NiAs4 tetrahedra, edges with two equivalent CeAs6 pentagonal pyramids, edges with eight NiAs4 tetrahedra, and faces with two equivalent CeAs6 pentagonal pyramids. There are a spread of Ce–As bond distances ranging from 3.01–3.07 Å. In the second Ce3+ site, Ce3+ is bonded to six As3- atoms to form distorted CeAs6 pentagonal pyramids that share corners with four equivalent CeAs6 pentagonal pyramids, corners with two equivalent NiAs5 square pyramids, corners with twelve NiAs4 tetrahedra, edges with two equivalent CeAs6 pentagonal pyramids, an edgeedge with one NiAs5 square pyramid, edges with seven NiAs4 tetrahedra, and faces with two equivalent CeAs6 pentagonal pyramids. There are a spread of Ce–As bond distances ranging from 2.98–3.07 Å. There are eight inequivalent Ni+1.05+ sites. In the first Ni+1.05+ site, Ni+1.05+ is bonded to four As3- atoms to form NiAs4 tetrahedra that share corners with four CeAs6 pentagonal pyramids, corners with two equivalent NiAs5 square pyramids, corners with ten NiAs4 tetrahedra, an edgeedge with one CeAs6 pentagonal pyramid, edges with four equivalent NiAs5 square pyramids, and edges with three NiAs4 tetrahedra. There are a spread of Ni–As bond distances ranging from 2.26–2.42 Å. In the second Ni+1.05+ site, Ni+1.05+ is bonded in a trigonal planar geometry to three equivalent As3- atoms. All Ni–As bond lengths are 2.35 Å. In the third Ni+1.05+ site, Ni+1.05+ is bonded to five As3- atoms to form distorted NiAs5 square pyramids that share corners with four CeAs6 pentagonal pyramids, corners with four equivalent NiAs5 square pyramids, corners with eight NiAs4 tetrahedra, an edgeedge with one CeAs6 pentagonal pyramid, edges with four equivalent NiAs5 square pyramids, and edges with seven NiAs4 tetrahedra. There are a spread of Ni–As bond distances ranging from 2.39–2.67 Å. In the fourth Ni+1.05+ site, Ni+1.05+ is bonded in a trigonal planar geometry to three equivalent As3- atoms. All Ni–As bond lengths are 2.34 Å. In the fifth Ni+1.05+ site, Ni+1.05+ is bonded to four As3- atoms to form NiAs4 tetrahedra that share corners with six CeAs6 pentagonal pyramids, corners with two equivalent NiAs5 square pyramids, corners with five NiAs4 tetrahedra, edges with four CeAs6 pentagonal pyramids, and edges with four NiAs4 tetrahedra. There are two shorter (2.37 Å) and two longer (2.39 Å) Ni–As bond lengths. In the sixth Ni+1.05+ site, Ni+1.05+ is bonded to four As3- atoms to form NiAs4 tetrahedra that share corners with four CeAs6 pentagonal pyramids, corners with three equivalent NiAs5 square pyramids, corners with eight NiAs4 tetrahedra, edges with three CeAs6 pentagonal pyramids, an edgeedge with one NiAs5 square pyramid, and edges with four NiAs4 tetrahedra. There are a spread of Ni–As bond distances ranging from 2.40–2.42 Å. In the seventh Ni+1.05+ site, Ni+1.05+ is bonded to four As3- atoms to form NiAs4 tetrahedra that share corners with six CeAs6 pentagonal pyramids, a cornercorner with one NiAs5 square pyramid, corners with six NiAs4 tetrahedra, edges with four CeAs6 pentagonal pyramids, and edges with four NiAs4 tetrahedra. There are a spread of Ni–As bond distances ranging from 2.36–2.41 Å. In the eighth Ni+1.05+ site, Ni+1.05+ is bonded to four As3- atoms to form NiAs4 tetrahedra that share corners with four CeAs6 pentagonal pyramids, corners with eleven NiAs4 tetrahedra, edges with three CeAs6 pentagonal pyramids, edges with two equivalent NiAs5 square pyramids, and edges with three NiAs4 tetrahedra. There are a spread of Ni–As bond distances ranging from 2.36–2.42 Å. There are five inequivalent As3- sites. In the first As3- site, As3- is bonded in a 9-coordinate geometry to four equivalent Ce3+ and five Ni+1.05+ atoms. In the second As3- site, As3- is bonded in a 9-coordinate geometry to two equivalent Ce3+ and seven Ni+1.05+ atoms. In the third As3- site, As3- is bonded in a 3-coordinate geometry to nine Ni+1.05+ atoms. In the fourth As3- site, As3- is bonded in a 9-coordinate geometry to four equivalent Ce3+ and five Ni+1.05+ atoms. In the fifth As3- site, As3- is bonded in a 9-coordinate geometry to two equivalent Ce3+ and seven Ni+1.05+ atoms.

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2020-09-03. Materials Data on Ce6Ni20As13 by Materials Project. https://doi.org/10.17188/1758469

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