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DOE OSTI · 1740880

Materials Data on Ho7C2I12N by Materials Project

Abstract

Ho7C2NI12 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are seven inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to one C3- and five I1- atoms to form distorted HoCI5 octahedra that share corners with two HoC2I5 pentagonal bipyramids, an edgeedge with one HoCI5 octahedra, and edges with two HoC2I5 pentagonal bipyramids. The Ho–C bond length is 2.20 Å. There are a spread of Ho–I bond distances ranging from 2.96–3.33 Å. In the second Ho3+ site, Ho3+ is bonded to one C3- and five I1- atoms to form distorted HoCI5 octahedra that share an edgeedge with one HoCI5 octahedra and edges with two HoC2I5 pentagonal bipyramids. The Ho–C bond length is 2.19 Å. There are a spread of Ho–I bond distances ranging from 2.97–3.38 Å. In the third Ho3+ site, Ho3+ is bonded in a distorted single-bond geometry to two C3-, one N3-, and four I1- atoms. There are one shorter (2.59 Å) and one longer (2.62 Å) Ho–C bond lengths. The Ho–N bond length is 2.16 Å. There are a spread of Ho–I bond distances ranging from 3.06–3.24 Å. In the fourth Ho3+ site, Ho3+ is bonded in a distorted L-shaped geometry to two equivalent N3- and four I1- atoms. There are one shorter (2.18 Å) and one longer (2.19 Å) Ho–N bond lengths. There are a spread of Ho–I bond distances ranging from 3.29–3.37 Å. In the fifth Ho3+ site, Ho3+ is bonded to two C3- and five I1- atoms to form distorted HoC2I5 pentagonal bipyramids that share a cornercorner with one HoCI5 octahedra, a cornercorner with one HoC2I5 pentagonal bipyramid, edges with two HoCI5 octahedra, an edgeedge with one HoC2I5 pentagonal bipyramid, and a faceface with one HoC2I5 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 10°. There are one shorter (2.47 Å) and one longer (2.50 Å) Ho–C bond lengths. There are a spread of Ho–I bond distances ranging from 3.00–3.49 Å. In the sixth Ho3+ site, Ho3+ is bonded to two C3- and five I1- atoms to form distorted HoC2I5 pentagonal bipyramids that share a cornercorner with one HoCI5 octahedra, a cornercorner with one HoC2I5 pentagonal bipyramid, edges with two HoCI5 octahedra, an edgeedge with one HoC2I5 pentagonal bipyramid, and a faceface with one HoC2I5 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 3°. There are one shorter (2.50 Å) and one longer (2.51 Å) Ho–C bond lengths. There are a spread of Ho–I bond distances ranging from 3.01–3.41 Å. In the seventh Ho3+ site, Ho3+ is bonded in a distorted single-bond geometry to two C3-, one N3-, and four I1- atoms. There are one shorter (2.61 Å) and one longer (2.62 Å) Ho–C bond lengths. The Ho–N bond length is 2.17 Å. There are a spread of Ho–I bond distances ranging from 3.09–3.25 Å. There are two inequivalent C3- sites. In the first C3- site, C3- is bonded in a 6-coordinate geometry to five Ho3+ and one C3- atom. The C–C bond length is 1.44 Å. In the second C3- site, C3- is bonded in a 6-coordinate geometry to five Ho3+ and one C3- atom. N3- is bonded to four Ho3+ atoms to form NHo4 tetrahedra that share a cornercorner with one IHo4 trigonal pyramid, an edgeedge with one NHo4 tetrahedra, and an edgeedge with one IHo4 trigonal pyramid. There are twelve inequivalent I1- sites. In the first I1- site, I1- is bonded in a 2-coordinate geometry to two Ho3+ atoms. In the second I1- site, I1- is bonded in a distorted bent 120 degrees geometry to two Ho3+ atoms. In the third I1- site, I1- is bonded in a 2-coordinate geometry to two Ho3+ atoms. In the fourth I1- site, I1- is bonded in a distorted T-shaped geometry to three Ho3+ atoms. In the fifth I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms. In the sixth I1- site, I1- is bonded in a distorted L-shaped geometry to two Ho3+ atoms. In the seventh I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms. In the eighth I1- site, I1- is bonded to four Ho3+ atoms to form distorted IHo4 trigonal pyramids that share a cornercorner with one NHo4 tetrahedra and an edgeedge with one NHo4 tetrahedra. In the ninth I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms. In the tenth I1- site, I1- is bonded in a distorted L-shaped geometry to two Ho3+ atoms. In the eleventh I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms. In the twelfth I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms.

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2020-05-02. Materials Data on Ho7C2I12N by Materials Project. https://doi.org/10.17188/1740880

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