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DOE OSTI · 1748166

Materials Data on Pr2Ni22C3 by Materials Project

Abstract

Pr2Ni22C3 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a 12-coordinate geometry to twenty Ni and two equivalent C atoms. There are a spread of Pr–Ni bond distances ranging from 3.06–3.22 Å. Both Pr–C bond lengths are 3.06 Å. In the second Pr site, Pr is bonded in a 12-coordinate geometry to eighteen Ni atoms. There are a spread of Pr–Ni bond distances ranging from 2.81–3.36 Å. There are fifteen inequivalent Ni sites. In the first Ni site, Ni is bonded in a single-bond geometry to two Pr, three Ni, and one C atom. There are two shorter (2.42 Å) and one longer (2.52 Å) Ni–Ni bond lengths. The Ni–C bond length is 1.90 Å. In the second Ni site, Ni is bonded in a 12-coordinate geometry to one Pr, eleven Ni, and one C atom. There are a spread of Ni–Ni bond distances ranging from 2.30–2.68 Å. The Ni–C bond length is 2.55 Å. In the third Ni site, Ni is bonded to two equivalent Pr and ten Ni atoms to form NiPr2Ni10 cuboctahedra that share corners with four equivalent NiPr3Ni9 cuboctahedra, faces with four equivalent NiPrNi11 cuboctahedra, and faces with two equivalent CNi7 trigonal bipyramids. There are two shorter (2.48 Å) and four longer (2.66 Å) Ni–Ni bond lengths. In the fourth Ni site, Ni is bonded to one Pr and eleven Ni atoms to form distorted NiPrNi11 cuboctahedra that share corners with four NiPrNi11 cuboctahedra, a cornercorner with one CNi7 trigonal bipyramid, an edgeedge with one CNi7 trigonal bipyramid, and faces with five NiPr2Ni10 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.32–2.62 Å. In the fifth Ni site, Ni is bonded in a single-bond geometry to one Pr, four Ni, and one C atom. There are one shorter (2.45 Å) and one longer (2.66 Å) Ni–Ni bond lengths. The Ni–C bond length is 1.91 Å. In the sixth Ni site, Ni is bonded in a single-bond geometry to two Pr, four Ni, and one C atom. The Ni–C bond length is 1.89 Å. In the seventh Ni site, Ni is bonded to twelve Ni atoms to form NiNi12 cuboctahedra that share corners with two equivalent CNi7 trigonal bipyramids and faces with six NiPrNi11 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.47–2.56 Å. In the eighth Ni site, Ni is bonded in a single-bond geometry to two Pr, three Ni, and one C atom. The Ni–Ni bond length is 2.49 Å. The Ni–C bond length is 1.91 Å. In the ninth Ni site, Ni is bonded in a 1-coordinate geometry to one Pr and thirteen Ni atoms. There are a spread of Ni–Ni bond distances ranging from 2.46–2.76 Å. In the tenth Ni site, Ni is bonded in a single-bond geometry to two Pr, three Ni, and one C atom. The Ni–Ni bond length is 2.43 Å. The Ni–C bond length is 1.92 Å. In the eleventh Ni site, Ni is bonded in a single-bond geometry to two equivalent Pr, seven Ni, and one C atom. The Ni–Ni bond length is 2.48 Å. The Ni–C bond length is 1.83 Å. In the twelfth Ni site, Ni is bonded in a single-bond geometry to two equivalent Pr, two Ni, and one C atom. The Ni–Ni bond length is 2.41 Å. The Ni–C bond length is 1.89 Å. In the thirteenth Ni site, Ni is bonded to three Pr and nine Ni atoms to form distorted NiPr3Ni9 cuboctahedra that share corners with eight NiPr2Ni10 cuboctahedra, a cornercorner with one CNi7 trigonal bipyramid, an edgeedge with one CNi7 trigonal bipyramid, and faces with three NiPrNi11 cuboctahedra. Both Ni–Ni bond lengths are 2.41 Å. In the fourteenth Ni site, Ni is bonded in a single-bond geometry to two Pr, five Ni, and one C atom. The Ni–C bond length is 1.93 Å. In the fifteenth Ni site, Ni is bonded in a water-like geometry to two equivalent Pr, three Ni, and two equivalent C atoms. There is one shorter (1.94 Å) and one longer (1.97 Å) Ni–C bond length. There are two inequivalent C sites. In the first C site, C is bonded to seven Ni atoms to form distorted CNi7 trigonal bipyramids that share corners with four NiPrNi11 cuboctahedra, edges with three NiPrNi11 cuboctahedra, and a faceface with one NiPr2Ni10 cuboctahedra. In the second C site, C is bonded in a 6-coordinate geometry to one Pr and six Ni atoms.

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2019-01-12. Materials Data on Pr2Ni22C3 by Materials Project. https://doi.org/10.17188/1748166

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