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DOE OSTI2020

Materials Data on Ho2Fe17H3 by Materials Project

Ho2Fe17H3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 3-coordinate geometry to eight Fe and three equivalent H atoms. There are two shorter (2.89 Å) and six longer (3.20 Å) Ho–Fe bond lengths. All Ho–H bond lengths are 2.50 Å. In the second Ho site, Ho is bonded in a trigonal planar geometry to three equivalent H atoms. All Ho–H bond lengths are 2.44 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent Ho and ten Fe atoms to form FeHo2Fe10 cuboctahedra that share corners with four equivalent FeHo2Fe10 cuboctahedra, corners with two equivalent HHo2Fe4 octahedra, faces with six equivalent FeHo2Fe10 cuboctahedra, and faces with four equivalent HHo2Fe4 octahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Fe–Fe bond distances ranging from 2.43–2.61 Å. In the second Fe site, Fe is bonded in a single-bond geometry to four Fe and one H atom. Both Fe–Fe bond lengths are 2.73 Å. The Fe–H bond length is 1.82 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 (2.38 Å) and three longer (2.66 Å) Fe–Fe bond lengths. In the fourth Fe site, Fe is bonded in a single-bond geometry to three Fe and one H atom. The Fe–H bond length is 1.90 Å. H is bonded to two Ho and four Fe atoms to form HHo2Fe4 octahedra that share corners with two equivalent FeHo2Fe10 cuboctahedra, corners with four equivalent HHo2Fe4 octahedra, and faces with four equivalent FeHo2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 60°.

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 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 Ho2Fe17C3 by Materials Project

Ho2Fe17C3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Ho is bonded in a distorted trigonal planar geometry to four Fe and three equivalent C atoms. There are one shorter (3.07 Å) and three longer (3.31 Å) Ho–Fe bond lengths. All Ho–C bond lengths are 2.49 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent 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 four equivalent FeHo2Fe10 cuboctahedra, and faces with four equivalent CHo2Fe4 octahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of Fe–Fe bond distances ranging from 2.44–2.65 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 1.87 Å. In the third Fe site, Fe is bonded in a single-bond geometry to three Fe and one C atom. The Fe–Fe bond length is 2.66 Å. The Fe–C bond length is 1.91 Å. In the fourth Fe site, Fe is bonded in a 2-coordinate geometry to one Ho and thirteen Fe atoms. The Fe–Fe bond length is 2.38 Å. C is bonded to two equivalent 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 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 Ho(Fe5Si)2 by Materials Project

HoFe10Si2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Ho is bonded in a 12-coordinate geometry to sixteen Fe and four equivalent Si atoms. There are a spread of Ho–Fe bond distances ranging from 2.93–3.18 Å. All Ho–Si bond lengths are 3.09 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded in a 10-coordinate geometry to one Ho, eleven Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.33–2.91 Å. Both Fe–Si bond lengths are 2.60 Å. In the second Fe site, Fe is bonded in a 10-coordinate geometry to one Ho, eleven Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.41–2.67 Å. Both Fe–Si bond lengths are 2.53 Å. In the third Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Ho, eight Fe, and two equivalent Si atoms. All Fe–Fe bond lengths are 2.44 Å. Both Fe–Si bond lengths are 2.61 Å. In the fourth Fe site, Fe is bonded to two equivalent Ho, eight Fe, and two equivalent Si atoms to form distorted FeHo2Fe8Si2 cuboctahedra that share corners with four equivalent SiHo2Fe10 cuboctahedra, corners with ten equivalent FeHo2Fe8Si2 cuboctahedra, edges with two equivalent SiHo2Fe10 cuboctahedra, edges with four equivalent FeHo2Fe8Si2 cuboctahedra, faces with four equivalent SiHo2Fe10 cuboctahedra, and faces with six equivalent FeHo2Fe8Si2 cuboctahedra. Both Fe–Fe bond lengths are 2.38 Å. Both Fe–Si bond lengths are 2.39 Å. Si is bonded to two equivalent Ho and ten Fe atoms to form distorted SiHo2Fe10 cuboctahedra that share corners with six equivalent SiHo2Fe10 cuboctahedra, corners with eight equivalent FeHo2Fe8Si2 cuboctahedra, edges with three equivalent SiHo2Fe10 cuboctahedra, edges with four equivalent FeHo2Fe8Si2 cuboctahedra, a faceface with one SiHo2Fe10 cuboctahedra, and faces with eight equivalent FeHo2Fe8Si2 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(FeGe)2 by Materials Project

HoFe2Ge2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho is bonded in a 8-coordinate geometry to eight equivalent Fe and eight equivalent Ge atoms. All Ho–Fe bond lengths are 3.32 Å. All Ho–Ge bond lengths are 3.05 Å. Fe is bonded to four equivalent Ho and four equivalent Ge atoms to form a mixture of edge, corner, and face-sharing FeHo4Ge4 tetrahedra. All Fe–Ge bond lengths are 2.43 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Ho, four equivalent Fe, and one Ge atom. The Ge–Ge bond length is 2.51 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(Fe2Ge)2 by Materials Project

HoFe4Ge2 crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Ho is bonded in a 6-coordinate geometry to twelve equivalent Fe and six equivalent Ge atoms. There are four shorter (3.17 Å) and eight longer (3.27 Å) Ho–Fe bond lengths. There are two shorter (2.91 Å) and four longer (2.94 Å) Ho–Ge bond lengths. Fe is bonded in a 3-coordinate geometry to three equivalent Ho and three equivalent Ge atoms. There are one shorter (2.43 Å) and two longer (2.44 Å) Fe–Ge bond lengths. Ge is bonded in a 9-coordinate geometry to three equivalent Ho and six equivalent Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Al2FeP2(HO)18 by Materials Project

Fe(OH)2(AlPO4(H2O)2)2(H2O)4 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one iron dihydroxide molecule; four water molecules; and one AlPO4(H2O)2 sheet oriented in the (0, 0, 1) direction. In the AlPO4(H2O)2 sheet, there are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra and corners with four equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of Al–O bond distances ranging from 1.89–2.00 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of Al–O bond distances ranging from 1.87–1.96 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three AlO6 octahedra. The corner-sharing octahedra tilt angles range from 41–51°. There are a spread of P–O bond distances ranging from 1.52–1.64 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.67 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Al3+ and two H1+ atoms. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Al3+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Al3+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a water-like geometry to one P5+ and one H1+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Al3+, one P5+, and one H1+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho4FeSn8 by Materials Project

Ho4FeSn8 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are four inequivalent Ho sites. In the first Ho site, Ho is bonded in a 10-coordinate geometry to ten Sn atoms. There are a spread of Ho–Sn bond distances ranging from 3.19–3.48 Å. In the second Ho site, Ho is bonded in a 10-coordinate geometry to ten Sn atoms. There are a spread of Ho–Sn bond distances ranging from 3.19–3.33 Å. In the third Ho site, Ho is bonded in a 4-coordinate geometry to four equivalent Fe and ten Sn atoms. All Ho–Fe bond lengths are 3.48 Å. There are a spread of Ho–Sn bond distances ranging from 3.30–3.70 Å. In the fourth Ho site, Ho is bonded in a 10-coordinate geometry to ten Sn atoms. There are a spread of Ho–Sn bond distances ranging from 3.20–3.52 Å. Fe is bonded in a 5-coordinate geometry to four equivalent Ho and five Sn atoms. There are a spread of Fe–Sn bond distances ranging from 2.47–2.51 Å. There are eight inequivalent Sn sites. In the first Sn site, Sn is bonded in a 1-coordinate geometry to six Ho, one Fe, and two equivalent Sn atoms. Both Sn–Sn bond lengths are 2.97 Å. In the second Sn site, Sn is bonded in a 4-coordinate geometry to six Ho and two equivalent Sn atoms. Both Sn–Sn bond lengths are 3.08 Å. In the third Sn site, Sn is bonded in a 4-coordinate geometry to six Ho and two equivalent Sn atoms. In the fourth Sn site, Sn is bonded in a 4-coordinate geometry to six Ho and two equivalent Sn atoms. In the fifth Sn site, Sn is bonded in a 2-coordinate geometry to four Ho, two equivalent Fe, and four equivalent Sn atoms. All Sn–Sn bond lengths are 3.15 Å. In the sixth Sn site, Sn is bonded in a 8-coordinate geometry to four Ho and four equivalent Sn atoms. All Sn–Sn bond lengths are 3.15 Å. In the seventh Sn site, Sn is bonded in a 2-coordinate geometry to four Ho, two equivalent Fe, and four equivalent Sn atoms. In the eighth Sn site, Sn is bonded in a 8-coordinate geometry to four Ho and four equivalent Sn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(FeSi)2 by Materials Project

HoFe2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho3+ is bonded in a distorted body-centered cubic geometry to eight equivalent Si4- atoms. All Ho–Si bond lengths are 3.07 Å. Fe+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing FeSi4 tetrahedra. All Fe–Si bond lengths are 2.26 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Ho3+, four equivalent Fe+2.50+, and one Si4- atom. The Si–Si bond length is 2.54 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho(FeB)2 by Materials Project

Ho(FeB)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ho is bonded in a 8-coordinate geometry to eight equivalent Fe and eight equivalent B atoms. All Ho–Fe bond lengths are 2.94 Å. All Ho–B bond lengths are 2.94 Å. Fe is bonded in a 4-coordinate geometry to four equivalent Ho and four equivalent B atoms. All Fe–B bond lengths are 2.00 Å. B is bonded in a 4-coordinate geometry to four equivalent Ho and four equivalent Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho2Ga3(Fe7C)2 by Materials Project

Ho2Ga3(Fe7C)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ho is bonded in a distorted bent 120 degrees geometry to six Fe, three Ga, and two equivalent C atoms. There are a spread of Ho–Fe bond distances ranging from 3.03–3.31 Å. There are two shorter (3.32 Å) and one longer (3.38 Å) Ho–Ga bond lengths. Both Ho–C bond lengths are 2.51 Å. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded in a 1-coordinate geometry to one Ho, ten Fe, and three Ga atoms. There are a spread of Fe–Fe bond distances ranging from 2.32–2.78 Å. There are one shorter (2.65 Å) and two longer (2.66 Å) Fe–Ga bond lengths. In the second Fe site, Fe is bonded to three equivalent Ho, seven Fe, and two equivalent Ga atoms to form FeHo3Ga2Fe7 cuboctahedra that share corners with four equivalent FeHo3Ga2Fe7 cuboctahedra, corners with five GaHo2Fe10 cuboctahedra, corners with four equivalent CHo2Fe4 octahedra, an edgeedge with one FeHo3Ga2Fe7 cuboctahedra, edges with three GaHo2Fe10 cuboctahedra, a faceface with one FeHo3Ga2Fe7 cuboctahedra, faces with three GaHo2Fe10 cuboctahedra, and faces with two equivalent CHo2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 63–69°. There are a spread of Fe–Fe bond distances ranging from 2.50–2.60 Å. Both Fe–Ga bond lengths are 2.48 Å. In the third Fe site, Fe is bonded in a single-bond geometry to three Fe, two Ga, and one C atom. The Fe–Fe bond length is 2.61 Å. There are one shorter (2.49 Å) and one longer (2.50 Å) Fe–Ga bond lengths. The Fe–C bond length is 1.91 Å. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Ho, eight Fe, and two equivalent Ga atoms. Both Fe–Fe bond lengths are 2.51 Å. Both Fe–Ga bond lengths are 2.46 Å. In the fifth Fe site, Fe is bonded in a single-bond geometry to four Fe, two Ga, and one C atom. There are one shorter (2.44 Å) and one longer (2.45 Å) Fe–Ga bond lengths. The Fe–C bond length is 1.84 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to two equivalent Ho and ten Fe atoms to form distorted GaHo2Fe10 cuboctahedra that share corners with four equivalent GaHo2Fe10 cuboctahedra, corners with six equivalent FeHo3Ga2Fe7 cuboctahedra, edges with two equivalent FeHo3Ga2Fe7 cuboctahedra, faces with two equivalent FeHo3Ga2Fe7 cuboctahedra, faces with four equivalent GaHo2Fe10 cuboctahedra, and faces with four equivalent CHo2Fe4 octahedra. In the second Ga site, Ga is bonded to two equivalent Ho and ten Fe atoms to form distorted GaHo2Fe10 cuboctahedra that share corners with two equivalent FeHo3Ga2Fe7 cuboctahedra, corners with four GaHo2Fe10 cuboctahedra, corners with two equivalent CHo2Fe4 octahedra, edges with two equivalent FeHo3Ga2Fe7 cuboctahedra, faces with two equivalent FeHo3Ga2Fe7 cuboctahedra, faces with four GaHo2Fe10 cuboctahedra, and faces with two equivalent CHo2Fe4 octahedra. The corner-sharing octahedral tilt angles are 46°. C is bonded to two equivalent Ho and four Fe atoms to form CHo2Fe4 octahedra that share corners with two equivalent GaHo2Fe10 cuboctahedra, corners with four equivalent FeHo3Ga2Fe7 cuboctahedra, corners with two equivalent CHo2Fe4 octahedra, faces with two equivalent FeHo3Ga2Fe7 cuboctahedra, and faces with four GaHo2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 63°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HoTiFe11N by Materials Project

HoTiFe11N crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. Ho is bonded in a linear geometry to one Ti, ten Fe, and two equivalent N atoms. The Ho–Ti bond length is 3.17 Å. There are a spread of Ho–Fe bond distances ranging from 3.08–3.30 Å. Both Ho–N bond lengths are 2.40 Å. Ti is bonded in a 1-coordinate geometry to one Ho and thirteen Fe atoms. There are a spread of Ti–Fe bond distances ranging from 2.37–2.92 Å. There are six inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent Ho, one Ti, and nine Fe atoms to form distorted FeHo2TiFe9 cuboctahedra that share corners with ten equivalent FeHo2TiFe9 cuboctahedra, corners with two equivalent NHo2Fe4 octahedra, edges with four equivalent FeHo2TiFe9 cuboctahedra, faces with six equivalent FeHo2TiFe9 cuboctahedra, and faces with two equivalent NHo2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 67–69°. There are a spread of Fe–Fe bond distances ranging from 2.39–2.63 Å. In the second Fe site, Fe is bonded in a single-bond geometry to six Fe and one N atom. Both Fe–Fe bond lengths are 2.63 Å. The Fe–N bond length is 1.92 Å. In the third Fe site, Fe is bonded in a single-bond geometry to two equivalent Ti, six Fe, and one N atom. Both Fe–Fe bond lengths are 2.66 Å. The Fe–N bond length is 1.91 Å. In the fourth Fe site, Fe is bonded in a single-bond geometry to one Ti, six Fe, and one N atom. Both Fe–Fe bond lengths are 2.67 Å. The Fe–N bond length is 1.91 Å. In the fifth Fe site, Fe is bonded in a 1-coordinate geometry to one Ti and eight Fe atoms. All Fe–Fe bond lengths are 2.95 Å. In the sixth Fe site, Fe is bonded in a 12-coordinate geometry to one Ho, two equivalent Ti, and eleven Fe atoms. The Fe–Fe bond length is 2.43 Å. N is bonded to two equivalent Ho and four Fe atoms to form NHo2Fe4 octahedra that share corners with eight equivalent FeHo2TiFe9 cuboctahedra, corners with two equivalent NHo2Fe4 octahedra, and faces with eight equivalent FeHo2TiFe9 cuboctahedra. The corner-sharing octahedral tilt angles are 2°.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Isoelectronic perturbations to f - d -electron hybridization and the enhancement of hidden order in URu 2 Si 2

Significance Phase transitions often manifest themselves in characteristic signatures in the electrical resistivity. Here, we track the temperature increase of the resistive signature of the hidden-order (HO) phase transition in URu 2 Si 2 , a mysterious phase with unknown order parameter. The application of pressure and the isoelectronic substitutions of Fe and Os ions for Ru are the only known perturbations to favor the HO phase. These perturbations are likely to cause increases in f - d -electron hybridization that lead to degeneracy and instabilities in the electronic band structure. The degeneracy is lifted by partial gapping of electronic states over the Fermi surface during the transition to HO. This and related investigations point to the importance of isoelectronic perturbations in generating emergent electronic phases.

Wolowiec, Christian T.↗
DOE OSTI2024

Coercive Fields Exceeding 30 T in the Mixed-Valence Single-Molecule Magnet (Cp iPr5 ) 2 Ho 2 I 3

Mixed-valence dilanthanide complexes of the type (Cp iPr5 ) 2 Ln 2 I 3 (Cp iPr5 = pentaisopropylcyclopentadienyl; Ln = Gd, Tb, Dy) featuring a direct Ln–Ln σ-bonding interaction have been shown to exhibit well-isolated high-spin ground states and, in the case of the Tb and Dy variants, a strong axial magnetic anisotropy that gives rise to a large magnetic coercivity. Here, we report the synthesis and characterization of two new mixed-valence dilanthanide compounds in this series, (Cp iPr5 ) 2 Ln 2 I 3 (1-Ln; Ln = Ho, Er). Both compounds feature a Ln–Ln bonding interaction, the first such interaction in any molecular compounds of Ho or Er. Like the Tb and Dy congeners, both complexes exhibit high-spin ground states arising from strong spin–spin coupling between the lanthanide 4f electrons and a single σ-type lanthanide–lanthanide bonding electron. Beyond these similarities, however, the magnetic properties of the two compounds diverge. In particular, 1-Er does not exhibit observable magnetic blocking or slow magnetic relaxation, while 1-Ho exhibits magnetic blocking below 28 K, which is the highest temperature among Ho-based single-molecule magnets, and a spin reversal barrier of 556(4) cm –1 . Additionally, variable-field magnetization data collected for 1-Ho reveal a coercive field of greater than 32 T below 8 K, more than 6-fold higher than observed for the bulk magnets SmCo 5 and Nd 2 Fe 14 B, and the highest coercive field reported to date for any single-molecule magnet or molecule-based magnetic material. Multiconfigurational calculations, supported by far-infrared magnetospectroscopy data, reveal that the stark differences in magnetic properties of 1-Ho and 1-Er arise from differences in the local magnetic anisotropy of the lanthanide centers.

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

Materials Data on Ba3HoUFeO9 by Materials Project

Ba3UHoFeO9 crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. there are six inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to nine O2- atoms. There are three shorter (2.73 Å) and six longer (3.01 Å) Ba–O bond lengths. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with six equivalent BaO12 cuboctahedra, faces with three equivalent UO6 octahedra, and faces with four FeO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.89–3.16 Å. In the third Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.64 Å) and three longer (2.65 Å) Ba–O bond lengths. In the fourth Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to nine O2- atoms. There are three shorter (2.76 Å) and six longer (3.00 Å) Ba–O bond lengths. In the fifth Ba2+ site, Ba2+ is bonded in a distorted hexagonal planar geometry to six O2- atoms. There are three shorter (2.65 Å) and three longer (2.68 Å) Ba–O bond lengths. In the sixth Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to nine O2- atoms. There are three shorter (2.76 Å) and six longer (3.01 Å) Ba–O bond lengths. There are two inequivalent U6+ sites. In the first U6+ site, U6+ is bonded in an octahedral geometry to six O2- atoms. There are three shorter (2.08 Å) and three longer (2.09 Å) U–O bond lengths. In the second U6+ site, U6+ is bonded to six O2- atoms to form UO6 octahedra that share corners with three equivalent FeO6 octahedra and faces with three equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (2.04 Å) and three longer (2.15 Å) U–O bond lengths. There are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded in a 3-coordinate geometry to three equivalent O2- atoms. All Ho–O bond lengths are 2.17 Å. In the second Ho3+ site, Ho3+ is bonded in a 3-coordinate geometry to three equivalent O2- atoms. All Ho–O bond lengths are 2.18 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent FeO6 octahedra and a faceface with one BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 6°. There are three shorter (1.97 Å) and three longer (2.24 Å) Fe–O bond lengths. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent UO6 octahedra, corners with three equivalent FeO6 octahedra, and faces with three equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–6°. There are three shorter (2.03 Å) and three longer (2.07 Å) Fe–O bond lengths. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to four Ba2+ and one U6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to four Ba2+ and one U6+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ba2+, one Ho3+, and two Fe3+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to three Ba2+, one U6+, and one Fe3+ atom. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to four Ba2+ and one U6+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Ho3+, and one Fe3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Magnetic functionalization and catalytic behavior of magnetic nanoparticles during laser photochemical graphitization of polyimide

We report laser-assisted photochemical graphitization of polyimides (PIs) into functional magnetic nanocomposites using laser irradiation of PI in the presence of magnetite nanoparticles (MNPs). PI Kapton sheets covered with MNP were photochemically treated under ambient conditions using a picosecond pulsed laser (1064 nm) to obtain an electrically conductive material. Scanning electron microscopy of the treated material revealed a layered magnetic nanoparticle/graphite (MNP/graphite) nanocomposite structure. Four probe conductivity measurements indicated that the nanocomposite has an electrical conductivity of 1550 ± 60 S/m. Superconducting quantum interference device magnetometer-based magnetic characterization of the treated material revealed an anisotropic ferromagnetic response in the MNP/graphite nanocomposite compared to the isotropic response of MNP. Raman spectroscopy of the MNP/graphite nanocomposite revealed a fourfold improvement in graphitization, suppression in disorder, and decreased nitrogenous impurities compared to the graphitic material obtained from laser treatment of just PI sheets. X-ray photoelectron spectroscopy, x-ray diffraction, and energy-dispersive x-ray spectroscopy were used to delineate the phase transformations of MNP during the formation of MNP/graphite nanocomposite. Post-mortem characterization indicates a possible photocatalytic effect of MNP during MNP/graphite nanocomposite formation. Under laser irradiation, MNP transformed from the initial Fe 3 O 4 phase to γ-Fe 2 O 3 and Fe 5 C 2 phases and acted as nucleation spots to catalyze the graphitization process of PI.

36 MATERIALS SCIENCE↗