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DOE OSTI2020

Materials Data on Ho4CdPt by Materials Project

Ho4PtCd crystallizes in the cubic F-43m space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a 3-coordinate geometry to three equivalent Pt and three equivalent Cd atoms. All Ho–Pt bond lengths are 2.85 Å. All Ho–Cd bond lengths are 3.40 Å. In the second Ho site, Ho is bonded in a distorted bent 150 degrees geometry to two equivalent Pt and two equivalent Cd atoms. Both Ho–Pt bond lengths are 2.83 Å. Both Ho–Cd bond lengths are 3.50 Å. In the third Ho site, Ho is bonded in a 4-coordinate geometry to two equivalent Pt and two equivalent Cd atoms. Both Ho–Pt bond lengths are 3.51 Å. Both Ho–Cd bond lengths are 3.26 Å. Pt is bonded in a 6-coordinate geometry to nine Ho atoms. Cd is bonded to nine Ho and three equivalent Cd atoms to form a mixture of distorted face and corner-sharing CdHo9Cd3 cuboctahedra. All Cd–Cd bond lengths are 3.16 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho4CdPd by Materials Project

Ho4PdCd crystallizes in the cubic F-43m space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a 3-coordinate geometry to three equivalent Pd and three equivalent Cd atoms. All Ho–Pd bond lengths are 2.86 Å. All Ho–Cd bond lengths are 3.38 Å. In the second Ho site, Ho is bonded in a distorted bent 150 degrees geometry to two equivalent Pd and two equivalent Cd atoms. Both Ho–Pd bond lengths are 2.85 Å. Both Ho–Cd bond lengths are 3.51 Å. In the third Ho site, Ho is bonded in a 4-coordinate geometry to two equivalent Pd and two equivalent Cd atoms. Both Ho–Pd bond lengths are 3.53 Å. Both Ho–Cd bond lengths are 3.25 Å. Pd is bonded in a 6-coordinate geometry to nine Ho atoms. Cd is bonded to nine Ho and three equivalent Cd atoms to form a mixture of distorted face and corner-sharing CdHo9Cd3 cuboctahedra. All Cd–Cd bond lengths are 3.17 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho5(In2Pt)2 by Materials Project

Ho5(PtIn2)2 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a 8-coordinate geometry to two equivalent Pt and six In atoms. Both Ho–Pt bond lengths are 2.82 Å. There are a spread of Ho–In bond distances ranging from 3.22–3.39 Å. In the second Ho site, Ho is bonded in a 10-coordinate geometry to four equivalent Pt and six In atoms. There are two shorter (2.95 Å) and two longer (2.96 Å) Ho–Pt bond lengths. There are a spread of Ho–In bond distances ranging from 3.33–3.42 Å. In the third Ho site, Ho is bonded in a distorted body-centered cubic geometry to eight In atoms. There are four shorter (3.23 Å) and four longer (3.33 Å) Ho–In bond lengths. Pt is bonded in a 9-coordinate geometry to six Ho and three In atoms. There are a spread of Pt–In bond distances ranging from 2.92–3.37 Å. There are two inequivalent In sites. In the first In site, In is bonded in a 1-coordinate geometry to eight Ho, two equivalent Pt, and one In atom. The In–In bond length is 3.36 Å. In the second In site, In is bonded in a 9-coordinate geometry to eight Ho, one Pt, and one In atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho3Mn3Ga2Ge by Materials Project

Ho3Mn3GeGa2 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 5-coordinate geometry to six Mn, four equivalent Ga, and one Ge atom. All Ho–Mn bond lengths are 3.24 Å. All Ho–Ga bond lengths are 2.94 Å. The Ho–Ge bond length is 2.92 Å. In the second Ho site, Ho is bonded in a 5-coordinate geometry to six Mn, four equivalent Ga, and one Ge atom. There are four shorter (3.23 Å) and two longer (3.24 Å) Ho–Mn bond lengths. All Ho–Ga bond lengths are 2.94 Å. The Ho–Ge bond length is 2.92 Å. There are two inequivalent Mn sites. In the first Mn site, Mn is bonded in a 12-coordinate geometry to six Ho, two equivalent Mn, two equivalent Ga, and two equivalent Ge atoms. Both Mn–Mn bond lengths are 2.83 Å. Both Mn–Ga bond lengths are 2.80 Å. Both Mn–Ge bond lengths are 2.59 Å. In the second Mn site, Mn is bonded in a 12-coordinate geometry to six Ho, two Mn, two equivalent Ga, and two equivalent Ge atoms. The Mn–Mn bond length is 2.83 Å. Both Mn–Ga bond lengths are 2.80 Å. Both Mn–Ge bond lengths are 2.59 Å. Ga is bonded in a 9-coordinate geometry to six Ho and three Mn atoms. Ge is bonded in a 9-coordinate geometry to three Ho and six Mn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho2Fe17N3 by Materials Project

Ho2Fe17N3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a distorted trigonal planar geometry to eight Fe and three equivalent N atoms. There are two shorter (3.00 Å) and six longer (3.26 Å) Ho–Fe bond lengths. All Ho–N bond lengths are 2.53 Å. In the second Ho site, Ho is bonded in a distorted trigonal planar geometry to eight Fe and three equivalent N atoms. There are two shorter (3.00 Å) and six longer (3.26 Å) Ho–Fe bond lengths. All Ho–N bond lengths are 2.53 Å. In the third Ho site, Ho is bonded in a trigonal planar geometry to three equivalent N atoms. All Ho–N bond lengths are 2.45 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded to two Ho and ten Fe atoms to form FeHo2Fe10 cuboctahedra that share corners with four equivalent FeHo2Fe10 cuboctahedra, corners with two equivalent NHo2Fe4 octahedra, faces with six equivalent FeHo2Fe10 cuboctahedra, and faces with four equivalent NHo2Fe4 octahedra. The corner-sharing octahedral tilt angles are 40°. There are eight shorter (2.48 Å) and two longer (2.65 Å) Fe–Fe bond lengths. In the second Fe site, Fe is bonded in a single-bond geometry to four Fe and one N atom. Both Fe–Fe bond lengths are 2.72 Å. The Fe–N bond length is 1.88 Å. In the third Fe site, Fe is bonded in a 2-coordinate geometry to one Ho and thirteen Fe atoms. There are one shorter (2.40 Å) and three longer (2.68 Å) Fe–Fe bond lengths. In the fourth Fe site, Fe is bonded in a single-bond geometry to three Fe and one N atom. The Fe–N bond length is 1.92 Å. N is bonded to two Ho and four Fe atoms to form NHo2Fe4 octahedra that share corners with two equivalent FeHo2Fe10 cuboctahedra, corners with four equivalent NHo2Fe4 octahedra, and faces with four equivalent FeHo2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 60°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho2Mn17C3 by Materials Project

Ho2Mn17C3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a distorted trigonal planar geometry to eight Mn and three equivalent C atoms. There are two shorter (3.00 Å) and six longer (3.23 Å) Ho–Mn bond lengths. All Ho–C bond lengths are 2.50 Å. In the second Ho site, Ho is bonded in a distorted trigonal planar geometry to eight Mn and three equivalent C atoms. There are two shorter (3.00 Å) and six longer (3.23 Å) Ho–Mn bond lengths. All Ho–C bond lengths are 2.50 Å. In the third Ho site, Ho is bonded in a trigonal planar geometry to three equivalent C atoms. All Ho–C bond lengths are 2.43 Å. There are four inequivalent Mn sites. In the first Mn site, Mn is bonded to two Ho and ten Mn atoms to form MnHo2Mn10 cuboctahedra that share corners with four equivalent MnHo2Mn10 cuboctahedra, corners with two equivalent CHo2Mn4 octahedra, faces with six equivalent MnHo2Mn10 cuboctahedra, and faces with four equivalent CHo2Mn4 octahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Mn–Mn bond distances ranging from 2.44–2.63 Å. In the second Mn site, Mn is bonded in a single-bond geometry to four Mn and one C atom. Both Mn–Mn bond lengths are 2.66 Å. The Mn–C bond length is 1.88 Å. In the third Mn site, Mn is bonded in a 2-coordinate geometry to one Ho and thirteen Mn atoms. There are one shorter (2.32 Å) and three longer (2.64 Å) Mn–Mn bond lengths. In the fourth Mn site, Mn is bonded in a single-bond geometry to three Mn and one C atom. The Mn–C bond length is 1.90 Å. C is bonded to two Ho and four Mn atoms to form CHo2Mn4 octahedra that share corners with two equivalent MnHo2Mn10 cuboctahedra, corners with four equivalent CHo2Mn4 octahedra, and faces with four equivalent MnHo2Mn10 cuboctahedra. The corner-sharing octahedral tilt angles are 60°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho5Bi3 by Materials Project

Ho5Bi3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are four inequivalent Ho sites. In the first Ho site, Ho is bonded in a 5-coordinate geometry to five Bi atoms. There are a spread of Ho–Bi bond distances ranging from 3.11–3.53 Å. In the second Ho site, Ho is bonded in a 6-coordinate geometry to six Bi atoms. There are a spread of Ho–Bi bond distances ranging from 3.12–3.51 Å. In the third Ho site, Ho is bonded to five Bi atoms to form distorted edge-sharing HoBi5 square pyramids. There are a spread of Ho–Bi bond distances ranging from 3.17–3.25 Å. In the fourth Ho site, Ho is bonded in a 5-coordinate geometry to five Bi atoms. There are a spread of Ho–Bi bond distances ranging from 3.06–3.37 Å. There are two inequivalent Bi sites. In the first Bi site, Bi is bonded in a 8-coordinate geometry to eight Ho atoms. In the second Bi site, Bi is bonded in a 9-coordinate geometry to nine Ho atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho2Fe17C3 by Materials Project

Ho2Fe17C3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a trigonal planar geometry to three equivalent C atoms. All Ho–C bond lengths are 2.47 Å. In the second Ho site, Ho is bonded in a distorted trigonal planar geometry to eight Fe and three equivalent C atoms. There are two shorter (2.97 Å) and six longer (3.24 Å) Ho–Fe bond lengths. All Ho–C bond lengths are 2.50 Å. In the third Ho site, Ho is bonded in a distorted trigonal planar geometry to eight Fe and three equivalent C atoms. There are two shorter (2.97 Å) and six longer (3.24 Å) Ho–Fe bond lengths. All Ho–C bond lengths are 2.50 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded to two Ho and ten Fe atoms to form FeHo2Fe10 cuboctahedra that share corners with four equivalent FeHo2Fe10 cuboctahedra, corners with two equivalent CHo2Fe4 octahedra, faces with six equivalent FeHo2Fe10 cuboctahedra, and faces with four equivalent CHo2Fe4 octahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Fe–Fe bond distances ranging from 2.47–2.64 Å. In the second Fe site, Fe is bonded in a single-bond geometry to four Fe and one C atom. Both Fe–Fe bond lengths are 2.72 Å. The Fe–C bond length is 1.86 Å. In the third Fe site, Fe is bonded in a 2-coordinate geometry to one Ho and thirteen Fe atoms. There are one shorter (2.37 Å) and three longer (2.68 Å) Fe–Fe bond lengths. In the fourth Fe site, Fe is bonded in a single-bond geometry to three Fe and one C atom. The Fe–C bond length is 1.91 Å. C is bonded to two Ho and four Fe atoms to form CHo2Fe4 octahedra that share corners with two equivalent FeHo2Fe10 cuboctahedra, corners with four equivalent CHo2Fe4 octahedra, and faces with four equivalent FeHo2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 60°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho12Al7Si by Materials Project

Ho12Al7Si crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a 4-coordinate geometry to six Al atoms. There are a spread of Ho–Al bond distances ranging from 2.96–3.70 Å. In the second Ho site, Ho is bonded in a 6-coordinate geometry to five Al and one Si atom. There are a spread of Ho–Al bond distances ranging from 3.02–3.31 Å. The Ho–Si bond length is 3.00 Å. In the third Ho site, Ho is bonded in a 5-coordinate geometry to five Al atoms. There are a spread of Ho–Al bond distances ranging from 3.09–3.48 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 9-coordinate geometry to nine Ho atoms. In the second Al site, Al is bonded in a body-centered cubic geometry to eight equivalent Ho atoms. In the third Al site, Al is bonded in a 10-coordinate geometry to nine Ho and one Al atom. The Al–Al bond length is 2.75 Å. Si is bonded in a 8-coordinate geometry to eight equivalent Ho atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho4CdNi by Materials Project

Ho4NiCd crystallizes in the cubic F-43m space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a 3-coordinate geometry to three equivalent Ni and three equivalent Cd atoms. All Ho–Ni bond lengths are 2.78 Å. All Ho–Cd bond lengths are 3.39 Å. In the second Ho site, Ho is bonded in a distorted bent 150 degrees geometry to two equivalent Ni and two equivalent Cd atoms. Both Ho–Ni bond lengths are 2.78 Å. Both Ho–Cd bond lengths are 3.45 Å. In the third Ho site, Ho is bonded in a 4-coordinate geometry to two equivalent Ni and two equivalent Cd atoms. Both Ho–Ni bond lengths are 3.44 Å. Both Ho–Cd bond lengths are 3.21 Å. Ni is bonded in a 6-coordinate geometry to nine Ho atoms. Cd is bonded to nine Ho and three equivalent Cd atoms to form a mixture of distorted face and corner-sharing CdHo9Cd3 cuboctahedra. All Cd–Cd bond lengths are 3.10 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho4CdIr by Materials Project

Ho4IrCd crystallizes in the cubic F-43m space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a 3-coordinate geometry to three equivalent Ir and three equivalent Cd atoms. All Ho–Ir bond lengths are 2.82 Å. All Ho–Cd bond lengths are 3.42 Å. In the second Ho site, Ho is bonded in a distorted bent 150 degrees geometry to two equivalent Ir and two equivalent Cd atoms. Both Ho–Ir bond lengths are 2.80 Å. Both Ho–Cd bond lengths are 3.48 Å. In the third Ho site, Ho is bonded in a 4-coordinate geometry to two equivalent Ir and two equivalent Cd atoms. Both Ho–Ir bond lengths are 3.47 Å. Both Ho–Cd bond lengths are 3.25 Å. Ir is bonded in a 6-coordinate geometry to nine Ho atoms. Cd is bonded to nine Ho and three equivalent Cd atoms to form a mixture of distorted face and corner-sharing CdHo9Cd3 cuboctahedra. All Cd–Cd bond lengths are 3.12 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho4Ni13C4 by Materials Project

Ho4Ni13C4 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 5-coordinate geometry to eleven Ni and four equivalent C atoms. There are a spread of Ho–Ni bond distances ranging from 2.62–3.19 Å. All Ho–C bond lengths are 2.69 Å. In the second Ho site, Ho is bonded in a 6-coordinate geometry to fourteen Ni atoms. There are a spread of Ho–Ni bond distances ranging from 2.65–3.02 Å. There are five inequivalent Ni sites. In the first Ni site, Ni is bonded to four equivalent Ho and eight Ni atoms to form NiHo4Ni8 cuboctahedra that share corners with four equivalent CNi6 octahedra and faces with two equivalent NiHo4Ni8 cuboctahedra. The corner-sharing octahedral tilt angles are 34°. There are four shorter (2.40 Å) and four longer (2.49 Å) Ni–Ni bond lengths. In the second Ni site, Ni is bonded in a distorted bent 150 degrees geometry to four Ho and two C atoms. There is one shorter (1.88 Å) and one longer (1.90 Å) Ni–C bond length. In the third Ni site, Ni is bonded in a linear geometry to four Ho and two equivalent C atoms. Both Ni–C bond lengths are 1.92 Å. In the fourth Ni site, Ni is bonded in a single-bond geometry to four Ho, three Ni, and one C atom. Both Ni–Ni bond lengths are 2.41 Å. The Ni–C bond length is 1.86 Å. In the fifth Ni site, Ni is bonded in a 3-coordinate geometry to three Ho and six Ni atoms. There are two inequivalent C sites. In the first C site, C is bonded in a 7-coordinate geometry to four equivalent Ho, two equivalent Ni, and one C atom. The C–C bond length is 1.35 Å. In the second C site, C is bonded to six Ni atoms to form CNi6 octahedra that share corners with two equivalent NiHo4Ni8 cuboctahedra and corners with two equivalent CNi6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NdHoFe14B by Materials Project

HoNdFe14B crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Ho is bonded in a 1-coordinate geometry to one Ho, two equivalent Nd, sixteen Fe, and one B atom. The Ho–Ho bond length is 3.59 Å. Both Ho–Nd bond lengths are 3.75 Å. There are a spread of Ho–Fe bond distances ranging from 3.01–3.35 Å. The Ho–B bond length is 2.86 Å. Nd is bonded in a 6-coordinate geometry to two equivalent Ho, sixteen Fe, and two equivalent B atoms. There are a spread of Nd–Fe bond distances ranging from 3.02–3.21 Å. Both Nd–B bond lengths are 3.26 Å. There are six inequivalent Fe sites. In the first Fe site, Fe is bonded in a distorted single-bond geometry to one Ho, one Nd, seven Fe, and one B atom. There are a spread of Fe–Fe bond distances ranging from 2.43–2.73 Å. The Fe–B bond length is 2.08 Å. In the second Fe site, Fe is bonded in a 2-coordinate geometry to one Ho, one Nd, and twelve Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.62–2.78 Å. In the third Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Ho, one Nd, and nine Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.37–2.50 Å. In the fourth Fe site, Fe is bonded in a distorted q6 geometry to one Ho, one Nd, and ten Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.45–2.53 Å. In the fifth Fe site, Fe is bonded in a distorted L-shaped geometry to two equivalent Nd, four Fe, and two equivalent B atoms. Both Fe–B bond lengths are 2.07 Å. In the sixth Fe site, Fe is bonded to two equivalent Ho, two equivalent Nd, and eight Fe atoms to form corner-sharing FeNd2Ho2Fe8 cuboctahedra. B is bonded in a 6-coordinate geometry to one Ho, two equivalent Nd, and six Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho2(CoNi)5 by Materials Project

Ho2(CoNi)5 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 6-coordinate geometry to six Co and twelve Ni atoms. There are four shorter (2.83 Å) and two longer (2.86 Å) Ho–Co bond lengths. There are eight shorter (3.14 Å) and four longer (3.15 Å) Ho–Ni bond lengths. In the second Ho site, Ho is bonded in a 6-coordinate geometry to ten Co and eight equivalent Ni atoms. There are a spread of Ho–Co bond distances ranging from 2.81–3.15 Å. All Ho–Ni bond lengths are 3.14 Å. There are three inequivalent Co sites. In the first Co site, Co is bonded in a 12-coordinate geometry to three Ho, two equivalent Co, and four equivalent Ni atoms. Both Co–Co bond lengths are 2.40 Å. All Co–Ni bond lengths are 2.44 Å. In the second Co site, Co is bonded in a 12-coordinate geometry to three Ho and six Ni atoms. There are four shorter (2.42 Å) and two longer (2.43 Å) Co–Ni bond lengths. In the third Co site, Co is bonded to four equivalent Ho, four equivalent Co, and four equivalent Ni atoms to form CoHo4Co4Ni4 cuboctahedra that share corners with four equivalent CoHo4Co4Ni4 cuboctahedra, corners with twelve NiHo4Co5Ni3 cuboctahedra, edges with two equivalent CoHo4Co4Ni4 cuboctahedra, edges with eight equivalent NiHo4Co5Ni3 cuboctahedra, faces with two equivalent CoHo4Co4Ni4 cuboctahedra, and faces with eight equivalent NiHo4Co5Ni3 cuboctahedra. All Co–Ni bond lengths are 2.45 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded to four equivalent Ho, four equivalent Co, and four equivalent Ni atoms to form NiHo4Co4Ni4 cuboctahedra that share corners with four equivalent CoHo4Co4Ni4 cuboctahedra, corners with twelve NiHo4Co5Ni3 cuboctahedra, edges with ten NiHo4Co5Ni3 cuboctahedra, and faces with ten NiHo4Co4Ni4 cuboctahedra. All Ni–Ni bond lengths are 2.45 Å. In the second Ni site, Ni is bonded to four Ho, five Co, and three Ni atoms to form NiHo4Co5Ni3 cuboctahedra that share corners with two equivalent CoHo4Co4Ni4 cuboctahedra, corners with fourteen NiHo4Co4Ni4 cuboctahedra, edges with two equivalent CoHo4Co4Ni4 cuboctahedra, edges with eight NiHo4Co4Ni4 cuboctahedra, faces with two equivalent CoHo4Co4Ni4 cuboctahedra, and faces with eight NiHo4Co4Ni4 cuboctahedra. There are one shorter (2.44 Å) and one longer (2.46 Å) Ni–Ni bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho3Ga2 by Materials Project

Ho3Ga2 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a 4-coordinate geometry to six Ga atoms. There are a spread of Ho–Ga bond distances ranging from 2.90–3.68 Å. In the second Ho site, Ho is bonded in a 5-coordinate geometry to five Ga atoms. There are a spread of Ho–Ga bond distances ranging from 2.99–3.51 Å. In the third Ho site, Ho is bonded in a 6-coordinate geometry to six Ga atoms. There are a spread of Ho–Ga bond distances ranging from 2.96–3.30 Å. There are four inequivalent Ga sites. In the first Ga site, Ga is bonded in a 8-coordinate geometry to eight equivalent Ho atoms. In the second Ga site, Ga is bonded in a body-centered cubic geometry to eight equivalent Ho atoms. In the third Ga site, Ga is bonded in a 9-coordinate geometry to nine Ho atoms. In the fourth Ga site, Ga is bonded in a 10-coordinate geometry to nine Ho and one Ga atom. The Ga–Ga bond length is 2.78 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho5S7 by Materials Project

Ho5S7 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded to six S atoms to form HoS6 octahedra that share corners with two equivalent HoS6 octahedra, corners with four equivalent HoS7 pentagonal bipyramids, edges with two equivalent HoS6 octahedra, and edges with six equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 56°. There are two shorter (2.67 Å) and four longer (2.73 Å) Ho–S bond lengths. In the second Ho site, Ho is bonded to six S atoms to form HoS6 octahedra that share corners with three HoS6 octahedra, corners with six equivalent HoS7 pentagonal bipyramids, edges with five equivalent HoS6 octahedra, and an edgeedge with one HoS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 0–56°. There are a spread of Ho–S bond distances ranging from 2.67–2.82 Å. In the third Ho site, Ho is bonded to seven S atoms to form distorted HoS7 pentagonal bipyramids that share corners with eight HoS6 octahedra, edges with four HoS6 octahedra, edges with two equivalent HoS7 pentagonal bipyramids, and faces with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 22–67°. There are a spread of Ho–S bond distances ranging from 2.73–2.92 Å. There are four inequivalent S sites. In the first S site, S is bonded in a square co-planar geometry to four equivalent Ho atoms. In the second S site, S is bonded to five Ho atoms to form distorted SHo5 trigonal bipyramids that share corners with four equivalent SHo4 tetrahedra, corners with six SHo5 trigonal bipyramids, edges with three equivalent SHo4 tetrahedra, and edges with six SHo5 trigonal bipyramids. In the third S site, S is bonded to four Ho atoms to form distorted SHo4 tetrahedra that share corners with three equivalent SHo4 tetrahedra, corners with nine SHo5 trigonal bipyramids, and edges with four SHo5 trigonal bipyramids. In the fourth S site, S is bonded to five Ho atoms to form SHo5 trigonal bipyramids that share corners with five equivalent SHo4 tetrahedra, corners with four equivalent SHo5 trigonal bipyramids, an edgeedge with one SHo4 tetrahedra, and edges with five SHo5 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Preliminary Evidence of Gas-Phase Water Splitting on Holmium Nitrogen Oxide Clusters

Preliminary Evidence of Gas-Phase Water Splitting on Holmium Nitrogen Oxide Clusters Christopher A. Zarzana1, Makayla R. Baxter , Introduction: Molecular hydrogen is a potential energy carrier that could be used to help implement a clean energy economy if it is generated from splitting of water. Improvements in the efficiencies of water-splitting electrolyzers relies on development of novel materials with enhanced performance. However, research in this area is slowed due to underdeveloped understanding of the mechanisms of device performance due to challenges interrogating the fundamental chemical reactions at play in bulk materials. Studies of the intrinsic reactivity of clusters that are representative of the reactive sites of these materials can increase understanding of the fundamental reaction mechanisms involved in hydrogen production, allowing for more efficient development of new water-splitting materials. Methods: Holmium tetranitrato ([Ho(NO3)4]-) clusters were generated in gas-phase using the electrospray ionization source of a Bruker (Billerica, MA, USA) micrOTOF-Q II quadrupole time-of-flight mass spectrometer. Spray solutions consisted of aqueous holmium (Ho) nitrate solutions (at nominally 3 mM) diluted to 30 µM in acetonitrile. The holmium (Ho) tetranitrato clusters were isolated using the quadrupole and were subsequently activated and allowed to react with background water in the collision cell. High resolution, high mass accuracy spectra were recorded using the time-of-flight. Mass accuracy was ensured using external calibration with Agilent (Santa Clara, CA, USA) ESI-L Low Concentration tuning mix. Preliminary data: Collisional activation of the holmium tetranitrato complexes ([Ln(NO3)4]-) resulted in an expected series of ions resulting from the loss of ·NO and ·NO2. This included an ion at m/z = 382.885 assigned as [HoO2(NO3)3]- (theoretical m/z=382.884, error=-1.2 ppm), resulting from loss of ·NO, and an ion at m/z=366.890 assigned as [HoO(NO3)3]- (theorical m/z=366.889, error=-1.8 ppm), resulting from loss of ·NO2. Additional ions were detected that would result from more complicated losses from [Ho(NO3)4]-, including ions at m/z=320.898 assigned as [HoO2(NO3)2]- (theoretical m/z=320.896, error=-4.9 ppm), at m/z=304.904 assigned as [HoO(NO3)2]- (theoretical m/z=304.901, error=-8.1 ppm, very low signal), and at m/z=288.908 assigned as [Ho(NO3)2]- (theoretical m/z=288.907, error=-3.4 ppm). This ion series would arise from loss of some combination of ·NO, ·NO2, and ·NO3, although it is not known whether these losses occur sequentially (e.g. loss of ·NO and ·NO3 to yield [HoO2(NO3)2]-) or as a single species (e.g. direct loss of N2O4). These ions were accompanied by a complementary series representing addition of a single water molecule. This included an ion at m/z=338.908 assigned as [HoO2(NO3)2H2O]- (theoretical m/z=338.907, error=-4.1 ppm), an ion at m/z=322.912 assigned as [HoO(NO3)2H2O]- (theoretical m/z=322.912, error=1.2 ppm), and an ion at m/z=306.918 assigned as [Ho(NO3)2H2O]-, (theoretical m/z=306.918, error=-3.7 ppm). An additional hydrated ion was observed at m/z=276.921 assigned as [HoO2(NO3) H2O]- (theoretical m/z=276.919, error=-7.3 ppm), although corresponding dehydrated ion was not observed. An additional ion was observed at m/z=367.898 that has been assigned as [Ho(NO3)3OH]- (theoretical m/z=367.897, error=-2.5 ppm). It is hypothesized that this ion arises from addition of water to [Ho(NO3)3]- followed by elimination of a hydrogen radical. Neither [Ho(NO3)3]- nor [Ho(NO3)3H2O]- were detected, suggesting that, if the hypothesis is correct, addition of water to [Ho(NO3)3]- and its subsequent splitting is rapid. Elimination of HNO3 from [Ho(NO3)4H2O]- could also yield [Ho(NO3)3OH]-; however, no [Ho(NO3)4H2O]- ions were observed. Novelty: Potential evidence of water splitting on gas-phase lanthanide clusters offers a way to study the intrinsic reactivity of hydrogen-generation materials.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on HoGe2Ir by Materials Project

HoIrGe2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 8-coordinate geometry to six equivalent Ir and nine Ge atoms. There are four shorter (3.23 Å) and two longer (3.29 Å) Ho–Ir bond lengths. There are a spread of Ho–Ge bond distances ranging from 2.95–3.51 Å. In the second Ho site, Ho is bonded in a 8-coordinate geometry to four equivalent Ir and ten Ge atoms. All Ho–Ir bond lengths are 3.17 Å. There are a spread of Ho–Ge bond distances ranging from 3.25–3.41 Å. Ir is bonded in a 10-coordinate geometry to five Ho and five Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.47–2.63 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to four Ho, three equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.72 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six Ho, two equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.48 Å. In the third Ge site, Ge is bonded in a 2-coordinate geometry to five Ho and two equivalent Ir atoms.

36 MATERIALS SCIENCE↗