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DOE OSTI2020

Materials Data on Gd3Y3Fe23 by Materials Project

Gd3Y3Fe23 crystallizes in the trigonal R3m space group. The structure is three-dimensional. Gd is bonded in a 12-coordinate geometry to twelve Fe atoms. There are a spread of Gd–Fe bond distances ranging from 2.89–3.06 Å. Y is bonded in a 12-coordinate geometry to twelve Fe atoms. There are a spread of Y–Fe bond distances ranging from 2.88–3.04 Å. There are eleven inequivalent Fe sites. In the first Fe site, Fe is bonded in a 10-coordinate geometry to two equivalent Gd, one Y, and ten Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.54–2.94 Å. In the second Fe site, Fe is bonded to two equivalent Gd, two equivalent Y, and eight Fe atoms to form a mixture of face and corner-sharing FeGd2Y2Fe8 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.46–2.63 Å. In the third Fe site, Fe is bonded to two equivalent Gd, two equivalent Y, and eight Fe atoms to form a mixture of face and corner-sharing FeGd2Y2Fe8 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.46–2.63 Å. In the fourth Fe site, Fe is bonded in a distorted q6 geometry to three equivalent Gd and nine Fe atoms. There are three shorter (2.52 Å) and three longer (2.60 Å) Fe–Fe bond lengths. In the fifth Fe site, Fe is bonded in a distorted q6 geometry to one Gd, two equivalent Y, and nine Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.52–2.61 Å. In the sixth Fe site, Fe is bonded in a distorted q6 geometry to three equivalent Y and nine Fe atoms. All Fe–Fe bond lengths are 2.53 Å. In the seventh Fe site, Fe is bonded in a distorted q6 geometry to two equivalent Gd, one Y, and nine Fe atoms. There are two shorter (2.52 Å) and one longer (2.61 Å) Fe–Fe bond lengths. In the eighth Fe site, Fe is bonded in a body-centered cubic geometry to eight Fe atoms. There are four shorter (2.54 Å) and one longer (2.55 Å) Fe–Fe bond lengths. In the ninth Fe site, Fe is bonded in a 3-coordinate geometry to three equivalent Gd and ten Fe atoms. In the tenth Fe site, Fe is bonded in a 10-coordinate geometry to one Gd, two equivalent Y, and ten Fe atoms. The Fe–Fe bond length is 2.93 Å. In the eleventh Fe site, Fe is bonded in a 10-coordinate geometry to three equivalent Y and ten Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr3Gd3Mn23 by Materials Project

Gd3Pr3Mn23 crystallizes in the trigonal R3m space group. The structure is three-dimensional. Gd is bonded in a 12-coordinate geometry to twelve Mn atoms. There are a spread of Gd–Mn bond distances ranging from 2.94–3.11 Å. Pr is bonded in a 12-coordinate geometry to twelve Mn atoms. There are a spread of Pr–Mn bond distances ranging from 2.96–3.18 Å. There are eleven inequivalent Mn sites. In the first Mn site, Mn is bonded in a distorted q6 geometry to two equivalent Gd, one Pr, and nine Mn atoms. There are a spread of Mn–Mn bond distances ranging from 2.38–2.67 Å. In the second Mn site, Mn is bonded to two equivalent Gd, two equivalent Pr, and eight Mn atoms to form a mixture of face and corner-sharing MnPr2Gd2Mn8 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.50–2.72 Å. In the third Mn site, Mn is bonded to two equivalent Gd, two equivalent Pr, and eight Mn atoms to form a mixture of face and corner-sharing MnPr2Gd2Mn8 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.48–2.71 Å. In the fourth Mn site, Mn is bonded in a 10-coordinate geometry to three equivalent Gd and ten Mn atoms. There are a spread of Mn–Mn bond distances ranging from 2.50–2.96 Å. In the fifth Mn site, Mn is bonded in a 10-coordinate geometry to one Gd, two equivalent Pr, and ten Mn atoms. There are a spread of Mn–Mn bond distances ranging from 2.62–2.98 Å. In the sixth Mn site, Mn is bonded in a 4-coordinate geometry to three equivalent Pr and ten Mn atoms. The Mn–Mn bond length is 2.56 Å. In the seventh Mn site, Mn is bonded in a 10-coordinate geometry to two equivalent Gd, one Pr, and ten Mn atoms. There are one shorter (2.56 Å) and one longer (2.64 Å) Mn–Mn bond lengths. In the eighth Mn site, Mn is bonded in a body-centered cubic geometry to eight Mn atoms. In the ninth Mn site, Mn is bonded in a distorted q6 geometry to three equivalent Gd and nine Mn atoms. All Mn–Mn bond lengths are 2.50 Å. In the tenth Mn site, Mn is bonded to one Gd, two equivalent Pr, and nine Mn atoms to form a mixture of distorted face and corner-sharing MnPr2GdMn9 cuboctahedra. Both Mn–Mn bond lengths are 2.51 Å. In the eleventh Mn site, Mn is bonded to three equivalent Pr and nine Mn atoms to form a mixture of face and corner-sharing MnPr3Mn9 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GdTm(FeNi4)2 by Materials Project

TmGd(FeNi4)2 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. Tm is bonded in a 6-coordinate geometry to three Fe and fifteen Ni atoms. There are one shorter (2.82 Å) and two longer (2.83 Å) Tm–Fe bond lengths. There are a spread of Tm–Ni bond distances ranging from 2.83–3.15 Å. Gd is bonded in a 6-coordinate geometry to three Fe and fifteen Ni atoms. There are two shorter (2.85 Å) and one longer (2.86 Å) Gd–Fe bond lengths. There are a spread of Gd–Ni bond distances ranging from 2.85–3.17 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent Tm, one Gd, and nine Ni atoms to form distorted FeGdTm2Ni9 cuboctahedra that share corners with twenty-one NiGd2TmFe3Ni6 cuboctahedra, edges with six FeGdTm2Ni9 cuboctahedra, faces with two equivalent FeGdTm2Ni9 cuboctahedra, and faces with twenty-one NiGd2TmFe3Ni6 cuboctahedra. There are a spread of Fe–Ni bond distances ranging from 2.42–2.84 Å. In the second Fe site, Fe is bonded to one Tm, two equivalent Gd, and nine Ni atoms to form distorted FeGd2TmNi9 cuboctahedra that share corners with twenty-one NiGd2TmFe3Ni6 cuboctahedra, edges with six FeGdTm2Ni9 cuboctahedra, faces with two equivalent FeGd2TmNi9 cuboctahedra, and faces with twenty-one NiGd2TmFe3Ni6 cuboctahedra. There are a spread of Fe–Ni bond distances ranging from 2.42–2.87 Å. There are six inequivalent Ni sites. In the first Ni site, Ni is bonded to one Tm, two equivalent Gd, three Fe, and six Ni atoms to form distorted NiGd2TmFe3Ni6 cuboctahedra that share corners with nine FeGdTm2Ni9 cuboctahedra, corners with twelve NiGd4Fe2Ni6 cuboctahedra, edges with six NiGd2TmFe3Ni6 cuboctahedra, faces with three FeGdTm2Ni9 cuboctahedra, and faces with twenty NiGd2TmFe3Ni6 cuboctahedra. There are four shorter (2.42 Å) and two longer (2.43 Å) Ni–Ni bond lengths. In the second Ni site, Ni is bonded to two equivalent Tm, one Gd, three Fe, and six Ni atoms to form distorted NiGdTm2Fe3Ni6 cuboctahedra that share corners with nine FeGdTm2Ni9 cuboctahedra, corners with twelve NiTm4Fe2Ni6 cuboctahedra, edges with six NiGd2TmFe3Ni6 cuboctahedra, faces with three FeGdTm2Ni9 cuboctahedra, and faces with twenty NiGdTm2Fe3Ni6 cuboctahedra. There are two shorter (2.41 Å) and four longer (2.43 Å) Ni–Ni bond lengths. In the third Ni site, Ni is bonded to four equivalent Tm, two equivalent Fe, and six Ni atoms to form distorted NiTm4Fe2Ni6 cuboctahedra that share corners with four equivalent FeGdTm2Ni9 cuboctahedra, corners with twenty NiGdTm2Fe3Ni6 cuboctahedra, edges with ten NiGd2Tm2Fe2Ni6 cuboctahedra, faces with six FeGdTm2Ni9 cuboctahedra, and faces with sixteen NiGd2TmFe3Ni6 cuboctahedra. There are two shorter (2.44 Å) and two longer (2.45 Å) Ni–Ni bond lengths. In the fourth Ni site, Ni is bonded to four equivalent Gd, two equivalent Fe, and six Ni atoms to form NiGd4Fe2Ni6 cuboctahedra that share corners with four equivalent FeGd2TmNi9 cuboctahedra, corners with twenty NiGd2TmFe3Ni6 cuboctahedra, edges with ten NiGd2Tm2Fe2Ni6 cuboctahedra, faces with six FeGdTm2Ni9 cuboctahedra, and faces with sixteen NiGd2TmFe3Ni6 cuboctahedra. There are two shorter (2.47 Å) and two longer (2.48 Å) Ni–Ni bond lengths. In the fifth Ni site, Ni is bonded to two equivalent Tm, two equivalent Gd, two equivalent Fe, and six Ni atoms to form distorted NiGd2Tm2Fe2Ni6 cuboctahedra that share corners with four equivalent FeGd2TmNi9 cuboctahedra, corners with twenty NiGdTm2Fe3Ni6 cuboctahedra, edges with ten NiGd2Tm2Fe2Ni6 cuboctahedra, faces with six FeGdTm2Ni9 cuboctahedra, and faces with sixteen NiGd2TmFe3Ni6 cuboctahedra. There are one shorter (2.43 Å) and one longer (2.49 Å) Ni–Ni bond lengths. In the sixth Ni site, Ni is bonded to two equivalent Tm, two equivalent Gd, two equivalent Fe, and six Ni atoms to form distorted NiGd2Tm2Fe2Ni6 cuboctahedra that share corners with four equivalent FeGdTm2Ni9 cuboctahedra, corners with twenty NiGd2TmFe3Ni6 cuboctahedra, edges with ten NiGd2Tm2Fe2Ni6 cuboctahedra, faces with six FeGdTm2Ni9 cuboctahedra, and faces with sixteen NiGd2TmFe3Ni6 cuboctahedra. There are one shorter (2.45 Å) and one longer (2.47 Å) Ni–Ni bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Gd2Ga8Co by Materials Project

Gd2CoGa8 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Gd is bonded to twelve Ga atoms to form a mixture of face and corner-sharing GdGa12 cuboctahedra. There are a spread of Gd–Ga bond distances ranging from 3.01–3.04 Å. Co is bonded in a body-centered cubic geometry to eight Ga atoms. All Co–Ga bond lengths are 2.49 Å. There are six inequivalent Ga sites. In the first Ga site, Ga is bonded in a 4-coordinate geometry to two equivalent Gd, two equivalent Co, and seven Ga atoms. There are a spread of Ga–Ga bond distances ranging from 2.55–3.03 Å. In the second Ga site, Ga is bonded in a 4-coordinate geometry to two equivalent Gd, two equivalent Co, and seven Ga atoms. There are one shorter (2.55 Å) and two longer (2.95 Å) Ga–Ga bond lengths. In the third Ga site, Ga is bonded in a 4-coordinate geometry to two equivalent Gd, two equivalent Co, and seven Ga atoms. Both Ga–Gd bond lengths are 3.01 Å. There are two shorter (2.95 Å) and four longer (3.03 Å) Ga–Ga bond lengths. In the fourth Ga site, Ga is bonded in a 4-coordinate geometry to two equivalent Gd, two equivalent Co, and seven Ga atoms. Both Ga–Gd bond lengths are 3.01 Å. Both Ga–Ga bond lengths are 2.95 Å. In the fifth Ga site, Ga is bonded in a distorted square co-planar geometry to four equivalent Gd atoms. In the sixth Ga site, Ga is bonded in a 4-coordinate geometry to four equivalent Gd and four Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GdI3O11 by Materials Project

GdO11I3 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one GdO11I3 sheet oriented in the (0, 1, 0) direction. Gd is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Gd–O bond distances ranging from 2.36–2.49 Å. There are eleven inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one I atom. The O–I bond length is 2.75 Å. In the second O site, O is bonded in a bent 150 degrees geometry to one Gd and one I atom. The O–I bond length is 1.84 Å. In the third O site, O is bonded in a bent 120 degrees geometry to one Gd and one I atom. The O–I bond length is 1.85 Å. In the fourth O site, O is bonded in a distorted single-bond geometry to one I atom. The O–I bond length is 1.84 Å. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Gd and one I atom. The O–I bond length is 1.85 Å. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Gd and one I atom. The O–I bond length is 1.84 Å. In the seventh O site, O is bonded in a 2-coordinate geometry to one Gd and one I atom. The O–I bond length is 1.85 Å. In the eighth O site, O is bonded in a bent 120 degrees geometry to one Gd and one I atom. The O–I bond length is 1.85 Å. In the ninth O site, O is bonded in a bent 120 degrees geometry to one Gd and one I atom. The O–I bond length is 1.84 Å. In the tenth O site, O is bonded in a single-bond geometry to one I atom. The O–I bond length is 1.81 Å. In the eleventh O site, O is bonded in a single-bond geometry to one Gd atom. There are three inequivalent I sites. In the first I site, I is bonded in a 3-coordinate geometry to four O atoms. In the second I site, I is bonded in a 3-coordinate geometry to three O atoms. In the third I site, I is bonded in a trigonal non-coplanar geometry to three O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Gd2Cl3 by Materials Project

Gd2Cl3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Gd sites. In the first Gd site, Gd is bonded in a 5-coordinate geometry to five Cl atoms. There are a spread of Gd–Cl bond distances ranging from 2.80–3.08 Å. In the second Gd site, Gd is bonded in a distorted pentagonal planar geometry to five Cl atoms. There are a spread of Gd–Cl bond distances ranging from 2.72–2.85 Å. There are three inequivalent Cl sites. In the first Cl site, Cl is bonded in a trigonal non-coplanar geometry to three equivalent Gd atoms. In the second Cl site, Cl is bonded in a rectangular see-saw-like geometry to four Gd atoms. In the third Cl site, Cl is bonded in a distorted T-shaped geometry to three Gd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Evaluation of 6-OxP-CD, an Oxime-based cyclodextrin as a viable medical countermeasure against nerve agent poisoning: Experimental and molecular dynamic simulation studies on its inclusion complexes with cyclosarin, soman and VX

The ability of the cyclodextrin-oxime construct 6-OxP-CD to bind and degrade the nerve agents Cyclosarin (GF), Soman (GD) and S -[2-[Di(propan-2-yl)amino]ethyl] O -ethyl methylphosphonothioate (VX) has been studied using 31 P-nuclear magnetic resonance (NMR) under physiological conditions. While 6-OxP-CD was found to degrade GF instantaneously under these conditions, it was found to form an inclusion complex with GD and significantly improve its degradation (t 1/2 ~ 2 hrs) relative over background (t 1/2 ~ 22 hrs). Consequently, effective formation of the 6-OxP-CD:GD inclusion complex results in the immediate neutralization of GD and thus preventing it from inhibiting its biological target. In contrast, NMR experiments did not find evidence for an inclusion complex between 6-OxP-CD and VX, and the agent’s degradation profile was identical to that of background degradation (t 1/2 ~ 24 hrs). As a complement to this experimental work, molecular dynamics (MD) simulations coupled with Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) calculations have been applied to the study of inclusion complexes between 6-OxP-CD and the three nerve agents. These studies provide data that informs the understanding of the different degradative interactions exhibited by 6-OxP-CD with each nerve agent as it is introduced in the CD cavity in two different orientations (up and down). For its complex with GF, it was found that the oxime in 6-OxP-CD lies in very close proximity (P GF …O Oxime ~ 4–5 Å) to the phosphorus center of GF in the ‘down GF ’ orientation for most of the simulation accurately describing the ability of 6-OxP-CD to degrade this nerve agent rapidly and efficiently. Further computational studies involving the center of masses (COMs) for both components (GF and 6-OxP-CD) also provided some insight on the nature of this inclusion complex. Distances between the COMs (ΔCOM) lie closer in space in the ‘down GF ’ orientation than in the ‘up GF ’ orientation; a correlation that seems to hold true not only for GF but also for its congener, GD. In the case of GD, calculations for the ‘down GD ’ orientation showed that the oxime functional group in 6-OxP-CD although lying in close proximity (P GD …O Oxime ~ 4–5 Å) to the phosphorus center of the nerve agent for most of the simulation, adopts another stable conformation that increase this distance to ~ 12–14 Å, thus explaining the ability of 6-OxP-CD to bind and degrade GD but with less efficiency as observed experimentally (t 1/2 ~ 4 hr. vs. immediate). Lastly, studies on the VX:6-OxP-CD system demonstrated that VX does not form a stable inclusion complex with the oxime-bearing cyclodextrin and as such does not interact in a way that is conducive to an accelerated degradation scenario. Collectively, these studies serve as a basic platform from which the development of new cyclodextrin scaffolds based on 6-OxP-CD can be designed in the development of medical countermeasures against these highly toxic chemical warfare agents.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2020

Materials Data on Gd2(Al3Ir)3 by Materials Project

Gd2(IrAl3)3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Gd is bonded in a 11-coordinate geometry to six Ir and eleven Al atoms. There are a spread of Gd–Ir bond distances ranging from 3.43–3.48 Å. There are a spread of Gd–Al bond distances ranging from 3.05–3.18 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 8-coordinate geometry to four equivalent Gd and eight Al atoms. There are a spread of Ir–Al bond distances ranging from 2.57–2.63 Å. In the second Ir site, Ir is bonded in a 8-coordinate geometry to four equivalent Gd and eight Al atoms. There are a spread of Ir–Al bond distances ranging from 2.57–2.63 Å. There are four inequivalent Al sites. In the first Al site, Al is bonded in a 3-coordinate geometry to three equivalent Gd and three Ir atoms. In the second Al site, Al is bonded in a 2-coordinate geometry to two equivalent Gd and two equivalent Ir atoms. In the third Al site, Al is bonded in a 3-coordinate geometry to two equivalent Gd and three Ir atoms. In the fourth Al site, Al is bonded in a 2-coordinate geometry to two equivalent Gd and two equivalent Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Gd2ReC2 by Materials Project

Gd2ReC2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Gd sites. In the first Gd site, Gd is bonded in a distorted rectangular see-saw-like geometry to four C atoms. There are a spread of Gd–C bond distances ranging from 2.55–2.73 Å. In the second Gd site, Gd is bonded to five C atoms to form a mixture of corner and edge-sharing GdC5 square pyramids. There are a spread of Gd–C bond distances ranging from 2.53–2.61 Å. Re is bonded in a distorted trigonal planar geometry to three C atoms. There are a spread of Re–C bond distances ranging from 1.93–2.04 Å. There are two inequivalent C sites. In the first C site, C is bonded to four Gd and two equivalent Re atoms to form a mixture of corner and edge-sharing CGd4Re2 octahedra. The corner-sharing octahedra tilt angles range from 12–40°. In the second C site, C is bonded to five Gd and one Re atom to form a mixture of corner and edge-sharing CGd5Re octahedra. The corner-sharing octahedra tilt angles range from 3–40°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GdMgIn by Materials Project

GdMgIn crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to four In atoms to form a mixture of distorted edge and corner-sharing MgIn4 tetrahedra. There are two shorter (2.96 Å) and two longer (3.01 Å) Mg–In bond lengths. In the second Mg site, Mg is bonded to four In atoms to form a mixture of distorted edge and corner-sharing MgIn4 tetrahedra. There are two shorter (2.95 Å) and two longer (3.00 Å) Mg–In bond lengths. There are two inequivalent Gd sites. In the first Gd site, Gd is bonded in a 5-coordinate geometry to five In atoms. There are four shorter (3.27 Å) and one longer (3.31 Å) Gd–In bond lengths. In the second Gd site, Gd is bonded in a 5-coordinate geometry to five In atoms. There are a spread of Gd–In bond distances ranging from 3.27–3.31 Å. There are two inequivalent In sites. In the first In site, In is bonded in a 9-coordinate geometry to three Mg and six Gd atoms. In the second In site, In is bonded in a 9-coordinate geometry to six Mg and three Gd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Gd2AlGe6 by Materials Project

Gd2AlGe6 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Gd is bonded in a 12-coordinate geometry to two equivalent Al and ten Ge atoms. There are one shorter (3.34 Å) and one longer (3.36 Å) Gd–Al bond lengths. There are a spread of Gd–Ge bond distances ranging from 3.09–3.36 Å. Al is bonded in a 5-coordinate geometry to four equivalent Gd and five Ge atoms. There are a spread of Al–Ge bond distances ranging from 2.51–2.60 Å. There are five inequivalent Ge sites. In the first Ge site, Ge is bonded in a 1-coordinate geometry to six equivalent Gd, one Al, and two Ge atoms. There are one shorter (2.54 Å) and one longer (2.59 Å) Ge–Ge bond lengths. In the second Ge site, Ge is bonded in a 8-coordinate geometry to six equivalent Gd and two Ge atoms. The Ge–Ge bond length is 2.64 Å. In the third Ge site, Ge is bonded in a 6-coordinate geometry to two equivalent Gd, one Al, and three Ge atoms. There are one shorter (2.51 Å) and two longer (2.56 Å) Ge–Ge bond lengths. In the fourth Ge site, Ge is bonded in a 1-coordinate geometry to two equivalent Gd, one Al, and three Ge atoms. The Ge–Ge bond length is 2.52 Å. In the fifth Ge site, Ge is bonded in a 1-coordinate geometry to two equivalent Gd, one Al, and three Ge atoms. The Ge–Ge bond length is 2.53 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3GdAl8 by Materials Project

Ca3GdAl8 is Hexagonal Laves-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three inequivalent Ca sites. In the first Ca site, Ca is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. There are one shorter (3.44 Å) and three longer (3.47 Å) Ca–Ca bond lengths. There are a spread of Ca–Al bond distances ranging from 3.31–3.33 Å. In the second Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Ca, one Gd, and twelve Al atoms. The Ca–Gd bond length is 3.44 Å. There are a spread of Ca–Al bond distances ranging from 3.31–3.33 Å. In the third Ca site, Ca is bonded in a 12-coordinate geometry to one Ca, three equivalent Gd, and twelve Al atoms. All Ca–Gd bond lengths are 3.47 Å. There are a spread of Ca–Al bond distances ranging from 3.30–3.33 Å. Gd is bonded in a 12-coordinate geometry to four Ca and twelve Al atoms. There are a spread of Gd–Al bond distances ranging from 3.30–3.33 Å. There are four inequivalent Al sites. In the first Al site, Al is bonded to four Ca, two equivalent Gd, and six Al atoms to form a mixture of edge, face, and corner-sharing AlCa4Gd2Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.81–2.84 Å. In the second Al site, Al is bonded to five Ca, one Gd, and six Al atoms to form a mixture of edge, face, and corner-sharing AlCa5GdAl6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.82–2.84 Å. In the third Al site, Al is bonded to three equivalent Ca, three equivalent Gd, and six Al atoms to form AlCa3Gd3Al6 cuboctahedra that share corners with eighteen AlCa4Gd2Al6 cuboctahedra, edges with six equivalent AlCa3Gd3Al6 cuboctahedra, and faces with eighteen AlCa4Gd2Al6 cuboctahedra. In the fourth Al site, Al is bonded to six Ca and six Al atoms to form AlCa6Al6 cuboctahedra that share corners with eighteen AlCa4Gd2Al6 cuboctahedra, edges with six equivalent AlCa6Al6 cuboctahedra, and faces with eighteen AlCa4Gd2Al6 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GdMg3Ni8 by Materials Project

Mg3GdNi8 is Hexagonal Laves-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to four Mg and twelve Ni atoms. There are one shorter (2.89 Å) and three longer (2.96 Å) Mg–Mg bond lengths. There are a spread of Mg–Ni bond distances ranging from 2.81–2.86 Å. In the second Mg site, Mg is bonded in a 12-coordinate geometry to three equivalent Mg, one Gd, and twelve Ni atoms. The Mg–Gd bond length is 3.06 Å. There are a spread of Mg–Ni bond distances ranging from 2.75–2.88 Å. In the third Mg site, Mg is bonded in a 12-coordinate geometry to one Mg, three equivalent Gd, and twelve Ni atoms. All Mg–Gd bond lengths are 3.03 Å. There are a spread of Mg–Ni bond distances ranging from 2.83–2.99 Å. Gd is bonded in a 12-coordinate geometry to four Mg and twelve Ni atoms. There are a spread of Gd–Ni bond distances ranging from 2.87–2.90 Å. There are four inequivalent Ni sites. In the first Ni site, Ni is bonded to four Mg, two equivalent Gd, and six Ni atoms to form a mixture of edge, face, and corner-sharing NiGd2Mg4Ni6 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.41–2.48 Å. In the second Ni site, Ni is bonded to five Mg, one Gd, and six Ni atoms to form a mixture of edge, face, and corner-sharing NiGdMg5Ni6 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.42–2.47 Å. In the third Ni site, Ni is bonded to six Mg and six Ni atoms to form NiMg6Ni6 cuboctahedra that share corners with eighteen NiGd2Mg4Ni6 cuboctahedra, edges with six equivalent NiMg6Ni6 cuboctahedra, and faces with eighteen NiGd2Mg4Ni6 cuboctahedra. In the fourth Ni site, Ni is bonded to three equivalent Mg, three equivalent Gd, and six Ni atoms to form NiGd3Mg3Ni6 cuboctahedra that share corners with eighteen NiGd2Mg4Ni6 cuboctahedra, edges with six equivalent NiGd3Mg3Ni6 cuboctahedra, and faces with eighteen NiGd2Mg4Ni6 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Gd2Al4CoGe2 by Materials Project

Gd2CoAl4Ge2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Gd is bonded in a 5-coordinate geometry to four equivalent Al and five equivalent Ge atoms. All Gd–Al bond lengths are 3.11 Å. There are four shorter (2.97 Å) and one longer (3.04 Å) Gd–Ge bond lengths. Co is bonded in a body-centered cubic geometry to eight Al atoms. All Co–Al bond lengths are 2.44 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 4-coordinate geometry to two equivalent Gd, two equivalent Co, five equivalent Al, and two equivalent Ge atoms. Both Al–Co bond lengths are 2.44 Å. There are one shorter (2.57 Å) and four longer (2.93 Å) Al–Al bond lengths. Both Al–Ge bond lengths are 2.80 Å. In the second Al site, Al is bonded in a 4-coordinate geometry to two equivalent Gd, two equivalent Co, five Al, and two equivalent Ge atoms. Both Al–Gd bond lengths are 3.11 Å. There are one shorter (2.57 Å) and four longer (2.93 Å) Al–Al bond lengths. Both Al–Ge bond lengths are 2.80 Å. In the third Al site, Al is bonded in a 4-coordinate geometry to two equivalent Gd, two equivalent Co, five Al, and two equivalent Ge atoms. Both Al–Gd bond lengths are 3.11 Å. All Al–Al bond lengths are 2.93 Å. Both Al–Ge bond lengths are 2.80 Å. Ge is bonded in a 9-coordinate geometry to five equivalent Gd and four equivalent Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GdSiPt by Materials Project

GdPtSi is hexagonal omega structure-derived structured and crystallizes in the tetragonal I4_1md space group. The structure is three-dimensional. Gd is bonded to six equivalent Pt and six equivalent Si atoms to form a mixture of edge and face-sharing GdSi6Pt6 cuboctahedra. All Gd–Pt bond lengths are 3.16 Å. There are four shorter (3.14 Å) and two longer (3.21 Å) Gd–Si bond lengths. There are three inequivalent Pt sites. In the first Pt site, Pt is bonded in a 3-coordinate geometry to six equivalent Gd and three equivalent Si atoms. There are two shorter (2.39 Å) and one longer (2.42 Å) Pt–Si bond lengths. In the second Pt site, Pt is bonded in a 3-coordinate geometry to six equivalent Gd and three equivalent Si atoms. All Pt–Gd bond lengths are 3.16 Å. There are two shorter (2.39 Å) and one longer (2.42 Å) Pt–Si bond lengths. In the third Pt site, Pt is bonded in a 3-coordinate geometry to six equivalent Gd and three equivalent Si atoms. All Pt–Gd bond lengths are 3.16 Å. There are two shorter (2.39 Å) and one longer (2.42 Å) Pt–Si bond lengths. Si is bonded in a distorted trigonal planar geometry to six equivalent Gd and three equivalent Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Gd6Mg23C by Materials Project

Mg23Gd6C crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 1-coordinate geometry to ten Mg and three equivalent Gd atoms. There are a spread of Mg–Mg bond distances ranging from 2.97–3.43 Å. All Mg–Gd bond lengths are 3.74 Å. In the second Mg site, Mg is bonded to eight Mg and four equivalent Gd atoms to form distorted MgGd4Mg8 cuboctahedra that share corners with twelve MgGd4Mg8 cuboctahedra, edges with two equivalent CGd6 octahedra, and faces with sixteen MgGd4Mg8 cuboctahedra. All Mg–Mg bond lengths are 2.91 Å. All Mg–Gd bond lengths are 3.70 Å. In the third Mg site, Mg is bonded in a body-centered cubic geometry to eight equivalent Mg atoms. In the fourth Mg site, Mg is bonded to nine Mg and three equivalent Gd atoms to form distorted MgGd3Mg9 cuboctahedra that share corners with twelve MgGd4Mg8 cuboctahedra, faces with twelve MgGd4Mg8 cuboctahedra, and a faceface with one CGd6 octahedra. All Mg–Mg bond lengths are 3.27 Å. All Mg–Gd bond lengths are 3.41 Å. Gd is bonded in a single-bond geometry to twelve Mg and one C atom. The Gd–C bond length is 2.57 Å. C is bonded to six equivalent Gd atoms to form CGd6 octahedra that share edges with twelve equivalent MgGd4Mg8 cuboctahedra and faces with eight equivalent MgGd3Mg9 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Impacts of anthropogenic gadolinium on the activity of the ammonia oxidizing bacterium Nitrosomonas europaea

Widespread use of gadolinium-based contrast agents in medical imaging has resulted in increased Gd inputs to municipal wastewater treatment plants. Others have reported that typical wastewater treatment does not attenuate Gd, resulting in discharges to natural waters. However, whether elevated Gd impacts the performance of biological treatment has not been investigated. We examined whether gadolinium chloride or Gd chelated with diethylenetriaminepentaacetic acid (DTPA) affected the activity of the model nitrifying bacterium Nitrosomonas europaea. At nominal GdCl 3 additions ranging from 1 to 500 µM, no impact was observed compared to the control. Most (>98%) of the added Gd precipitated, and extracellular GdPO 4 nanoparticles were observed. When chelated with DTPA, Gd remained soluble, but no statistically significant impact on ammonia oxidation was observed until the highest concentrations tested. At 300 and 500 µM Gd-DTPA, a temporary reduction of nitrite production relative to the control (effect size 1.3 mg l -1 and 1.5 mg l -1 , respectively, at 24 h) was seen. By itself, DTPA was highly inhibitory. Modeling suggested that DTPA likely chelated other metals, but adjusting the concentrations of the most abundant metals in the medium, calcium and magnesium, indicated that lowering their free ion activities was probably not the cause of inhibition. Complexation of other essential metals was more likely. Furthermore, our studies indicate that while the low bioavailability of Gd may limit its ecosystem impacts, the role of synthetic ligands used with Gd and other rare earth elements should e considered as the production, use and disposal of these elements increases.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

Second gadolinium loading to Super-Kamiokande

The first loading of gadolinium (Gd) into Super-Kamiokande in 2020 was successful, and the neutron capture efficiency on Gd reached 50%. To further increase the Gd neutron capture efficiency to 75%, 26.1 tons of Gd 2 (SO 4 ) 3 ∙ 8H 2 O was additionally loaded into Super-Kamiokande (SK) from May 31 to July 4, 2022. As the amount of loaded Gd 2 (SO 4 ) 3 ∙ 8H 2 O was doubled compared to the first loading, the capacity of the powder dissolving system was doubled. We also developed new batches of gadolinium sulfate with even further reduced radioactive impurities. In addition, a more efficient screening method was devised and implemented to evaluate these new batches of Gd 2 (SO 4 ) 3 ∙ 8H 2 O. Following the second loading, the Gd concentration in SK was measured to be 333.5 ± 2.5 ppm via an Atomic Absorption Spectrometer (AAS). From the mean neutron capture time constant of neutrons from an Am/Be calibration source, the Gd concentration was independently measured to be 332.7 ± 6.8(sys.) ± 1.1(stat.) ppm, consistent with the AAS result. Furthermore, during the loading the Gd concentration was monitored continually using the capture time constant of each spallation neutron produced by cosmic-ray muons, and the final neutron capture efficiency was shown to become 1.5 times higher than that of the first loaded phase, as expected.

Gadolinium↗