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DOE OSTI2020

Materials Data on Y2Fe4Si9 by Materials Project

Y2Fe4Si9 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Y is bonded in a 6-coordinate geometry to three equivalent Fe and eight Si atoms. All Y–Fe bond lengths are 3.21 Å. There are a spread of Y–Si bond distances ranging from 2.87–3.20 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded in a 7-coordinate geometry to ten Si atoms. There are a spread of Fe–Si bond distances ranging from 2.31–2.69 Å. In the second Fe site, Fe is bonded in a 10-coordinate geometry to three equivalent Y and seven Si atoms. There are four shorter (2.31 Å) and three longer (2.46 Å) Fe–Si bond lengths. There are five inequivalent Si sites. In the first Si site, Si is bonded in a 10-coordinate geometry to three equivalent Y, three equivalent Fe, and four Si atoms. There are one shorter (2.40 Å) and three longer (2.65 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 6-coordinate geometry to three equivalent Y, three equivalent Fe, and three equivalent Si atoms. All Si–Si bond lengths are 2.64 Å. In the third Si site, Si is bonded in a 4-coordinate geometry to one Y, four equivalent Fe, and six Si atoms. All Si–Si bond lengths are 2.50 Å. In the fourth Si site, Si is bonded in a 4-coordinate geometry to one Y, four equivalent Fe, and six Si atoms. All Si–Si bond lengths are 2.66 Å. In the fifth Si site, Si is bonded in a 8-coordinate geometry to six equivalent Fe and eight Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y4C4I3Br by Materials Project

(YCI)2Y2C2IBr crystallizes in the monoclinic Cm space group. The structure is two-dimensional and consists of one Y2C2IBr sheet oriented in the (0, 0, 1) direction and one YCI sheet oriented in the (0, 0, 1) direction. In the Y2C2IBr sheet, there are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 1-coordinate geometry to five C2- and three equivalent I1- atoms. There are a spread of Y–C bond distances ranging from 2.35–2.71 Å. There are two shorter (3.11 Å) and one longer (3.24 Å) Y–I bond lengths. In the second Y3+ site, Y3+ is bonded in a 8-coordinate geometry to five C2- and three equivalent Br1- atoms. There are a spread of Y–C bond distances ranging from 2.35–2.71 Å. There are two shorter (2.94 Å) and one longer (3.12 Å) Y–Br bond lengths. There are two inequivalent C2- sites. In the first C2- site, C2- is bonded in a 6-coordinate geometry to five Y3+ and one C2- atom. The C–C bond length is 1.33 Å. In the second C2- site, C2- is bonded in a 6-coordinate geometry to five Y3+ and one C2- atom. I1- is bonded in a 3-coordinate geometry to three equivalent Y3+ atoms. Br1- is bonded in a 3-coordinate geometry to three equivalent Y3+ atoms. In the YCI sheet, there are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 1-coordinate geometry to five C2- and three equivalent I1- atoms. There are a spread of Y–C bond distances ranging from 2.35–2.71 Å. There are two shorter (3.10 Å) and one longer (3.24 Å) Y–I bond lengths. In the second Y3+ site, Y3+ is bonded in a 1-coordinate geometry to five C2- and three equivalent I1- atoms. There are a spread of Y–C bond distances ranging from 2.35–2.70 Å. There are two shorter (3.10 Å) and one longer (3.23 Å) Y–I bond lengths. There are two inequivalent C2- sites. In the first C2- site, C2- is bonded in a 6-coordinate geometry to five Y3+ and one C2- atom. The C–C bond length is 1.33 Å. In the second C2- site, C2- is bonded in a 6-coordinate geometry to five Y3+ and one C2- atom. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a 3-coordinate geometry to three equivalent Y3+ atoms. In the second I1- site, I1- is bonded in a 3-coordinate geometry to three equivalent Y3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2AlCo3 by Materials Project

Y2Co3Al crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Y is bonded in a 9-coordinate geometry to four equivalent Y, nine equivalent Co, and three equivalent Al atoms. There are one shorter (3.02 Å) and three longer (3.22 Å) Y–Y bond lengths. There are three shorter (2.86 Å) and six longer (3.08 Å) Y–Co bond lengths. All Y–Al bond lengths are 3.13 Å. Co is bonded to six equivalent Y, four equivalent Co, and two equivalent Al atoms to form distorted CoY6Al2Co4 cuboctahedra that share corners with four equivalent AlY6Co6 cuboctahedra, corners with fourteen equivalent CoY6Al2Co4 cuboctahedra, edges with six equivalent CoY6Al2Co4 cuboctahedra, faces with six equivalent AlY6Co6 cuboctahedra, and faces with twelve equivalent CoY6Al2Co4 cuboctahedra. All Co–Co bond lengths are 2.68 Å. Both Co–Al bond lengths are 2.49 Å. Al is bonded to six equivalent Y and six equivalent Co atoms to form distorted AlY6Co6 cuboctahedra that share corners with six equivalent AlY6Co6 cuboctahedra, corners with twelve equivalent CoY6Al2Co4 cuboctahedra, edges with six equivalent AlY6Co6 cuboctahedra, and faces with eighteen equivalent CoY6Al2Co4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YMg3 by Materials Project

YMg3 is beta-derived structured and crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to eight Mg and four equivalent Y atoms to form MgY4Mg8 cuboctahedra that share corners with four equivalent YY2Mg10 cuboctahedra, corners with fourteen equivalent MgY4Mg8 cuboctahedra, edges with four equivalent YY2Mg10 cuboctahedra, edges with fourteen MgY4Mg8 cuboctahedra, faces with six equivalent YY2Mg10 cuboctahedra, and faces with fourteen MgY4Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.28–3.37 Å. There are two shorter (3.28 Å) and two longer (3.34 Å) Mg–Y bond lengths. In the second Mg site, Mg is bonded to nine Mg and three equivalent Y atoms to form MgY3Mg9 cuboctahedra that share corners with eighteen equivalent MgY3Mg9 cuboctahedra, edges with six equivalent YY2Mg10 cuboctahedra, edges with twelve MgY4Mg8 cuboctahedra, faces with six equivalent YY2Mg10 cuboctahedra, and faces with fourteen MgY4Mg8 cuboctahedra. There are two shorter (3.28 Å) and four longer (3.31 Å) Mg–Mg bond lengths. There are one shorter (3.34 Å) and two longer (3.36 Å) Mg–Y bond lengths. Y is bonded to ten Mg and two equivalent Y atoms to form YY2Mg10 cuboctahedra that share corners with four equivalent MgY4Mg8 cuboctahedra, corners with fourteen equivalent YY2Mg10 cuboctahedra, edges with two equivalent YY2Mg10 cuboctahedra, edges with sixteen MgY4Mg8 cuboctahedra, faces with two equivalent YY2Mg10 cuboctahedra, and faces with eighteen MgY4Mg8 cuboctahedra. Both Y–Y bond lengths are 3.28 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2Pt by Materials Project

PtY2 is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded to four equivalent Pt atoms to form a mixture of edge and corner-sharing YPt4 tetrahedra. There are a spread of Y–Pt bond distances ranging from 2.91–2.96 Å. In the second Y site, Y is bonded in a 3-coordinate geometry to three equivalent Pt atoms. There are one shorter (2.84 Å) and two longer (3.08 Å) Y–Pt bond lengths. Pt is bonded in a 7-coordinate geometry to seven Y atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y3(Al3Os)4 by Materials Project

Y3(OsAl3)4 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Y is bonded in a 5-coordinate geometry to four equivalent Os and eleven Al atoms. All Y–Os bond lengths are 3.38 Å. There are a spread of Y–Al bond distances ranging from 2.96–3.22 Å. There are two inequivalent Os sites. In the first Os site, Os is bonded in a body-centered cubic geometry to eight Al atoms. There are two shorter (2.39 Å) and six longer (2.60 Å) Os–Al bond lengths. In the second Os site, Os is bonded in a 12-coordinate geometry to four equivalent Y and eight Al atoms. There are four shorter (2.56 Å) and four longer (2.69 Å) Os–Al bond lengths. There are four inequivalent Al sites. In the first Al site, Al is bonded in a 3-coordinate geometry to three equivalent Y and three equivalent Os atoms. In the second Al site, Al is bonded in a 3-coordinate geometry to three equivalent Y and three Os atoms. In the third Al site, Al is bonded in a 2-coordinate geometry to two equivalent Y and two equivalent Os atoms. In the fourth Al site, Al is bonded in a distorted linear geometry to three equivalent Y and two equivalent Os atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YMg2 by Materials Project

Mg2Y is beta-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to nine Mg and three equivalent Y atoms to form distorted MgY3Mg9 cuboctahedra that share corners with six equivalent YY4Mg8 cuboctahedra, corners with twelve MgY3Mg9 cuboctahedra, edges with seven equivalent YY4Mg8 cuboctahedra, edges with eleven MgY3Mg9 cuboctahedra, faces with seven equivalent YY4Mg8 cuboctahedra, and faces with thirteen MgY3Mg9 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.25–3.49 Å. There are one shorter (3.26 Å) and two longer (3.41 Å) Mg–Y bond lengths. In the second Mg site, Mg is bonded to seven Mg and five equivalent Y atoms to form distorted MgY5Mg7 cuboctahedra that share corners with six equivalent YY4Mg8 cuboctahedra, corners with twelve MgY3Mg9 cuboctahedra, edges with five equivalent YY4Mg8 cuboctahedra, edges with thirteen MgY3Mg9 cuboctahedra, faces with eight equivalent YY4Mg8 cuboctahedra, and faces with twelve MgY3Mg9 cuboctahedra. There are two shorter (3.31 Å) and one longer (3.47 Å) Mg–Mg bond lengths. There are a spread of Mg–Y bond distances ranging from 3.34–3.49 Å. Y is bonded to eight Mg and four equivalent Y atoms to form YY4Mg8 cuboctahedra that share corners with six equivalent YY4Mg8 cuboctahedra, corners with twelve MgY3Mg9 cuboctahedra, edges with six equivalent YY4Mg8 cuboctahedra, edges with twelve MgY3Mg9 cuboctahedra, faces with five equivalent YY4Mg8 cuboctahedra, and faces with fifteen MgY3Mg9 cuboctahedra. There are two shorter (3.31 Å) and two longer (3.42 Å) Y–Y bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba3SrY8(CuO5)4 by Materials Project

Ba3SrY8(CuO5)4 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.64–3.30 Å. In the second Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.59–3.29 Å. In the third Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.63–3.30 Å. Sr2+ is bonded in a 1-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.51–3.05 Å. There are eight inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with five CuO5 square pyramids, edges with five YO7 pentagonal bipyramids, an edgeedge with one CuO5 square pyramid, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Y–O bond distances ranging from 2.29–2.39 Å. In the second Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with five CuO5 square pyramids, edges with five YO7 pentagonal bipyramids, an edgeedge with one CuO5 square pyramid, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Y–O bond distances ranging from 2.28–2.40 Å. In the third Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with five CuO5 square pyramids, edges with five YO7 pentagonal bipyramids, an edgeedge with one CuO5 square pyramid, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Y–O bond distances ranging from 2.28–2.38 Å. In the fourth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with five CuO5 square pyramids, edges with five YO7 pentagonal bipyramids, an edgeedge with one CuO5 square pyramid, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Y–O bond distances ranging from 2.29–2.40 Å. In the fifth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with four equivalent YO7 pentagonal bipyramids, edges with three YO7 pentagonal bipyramids, edges with two equivalent CuO5 square pyramids, a faceface with one YO7 pentagonal bipyramid, and a faceface with one CuO5 square pyramid. There are a spread of Y–O bond distances ranging from 2.33–2.38 Å. In the sixth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with four equivalent YO7 pentagonal bipyramids, edges with three YO7 pentagonal bipyramids, edges with two equivalent CuO5 square pyramids, a faceface with one YO7 pentagonal bipyramid, and a faceface with one CuO5 square pyramid. There are a spread of Y–O bond distances ranging from 2.30–2.38 Å. In the seventh Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with four equivalent YO7 pentagonal bipyramids, edges with three YO7 pentagonal bipyramids, edges with two equivalent CuO5 square pyramids, a faceface with one YO7 pentagonal bipyramid, and a faceface with one CuO5 square pyramid. There are a spread of Y–O bond distances ranging from 2.30–2.38 Å. In the eighth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with four equivalent YO7 pentagonal bipyramids, edges with three YO7 pentagonal bipyramids, edges with two equivalent CuO5 square pyramids, a faceface with one YO7 pentagonal bipyramid, and a faceface with one CuO5 square pyramid. There are a spread of Y–O bond distances ranging from 2.30–2.38 Å. There are four inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with five YO7 pentagonal bipyramids, edges with three YO7 pentagonal bipyramids, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Cu–O bond distances ranging from 2.00–2.33 Å. In the second Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with five YO7 pentagonal bipyramids, edges with three YO7 pentagonal bipyramids, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Cu–O bond distances ranging from 1.98–2.30 Å. In the third Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with five YO7 pentagonal bipyramids, edges with three YO7 pentagonal bipyramids, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Cu–O bond distances ranging from 1.99–2.31 Å. In the fourth Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with five YO7 pentagonal bipyramids, edges with three YO7 pentagonal bipyramids, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Cu–O bond distances ranging from 1.98–2.30 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ba2+, one Sr2+, two Y3+, and one Cu2+ atom to form distorted OBa2SrY2Cu octahedra that share corners with two equivalent OBa2SrY2Cu octahedra and edges with two equivalent OBaSr2Y2Cu octahedra. The corner-sharing octahedral tilt angles are 3°. In the second O2- site, O2- is bonded to three Ba2+, two Y3+, and one Cu2+ atom to form a mixture of distorted corner and edge-sharing OBa3Y2Cu octahedra. The corner-sharing octahedral tilt angles are 5°. In the third O2- site, O2- is bonded to one Ba2+, two equivalent Sr2+, two Y3+, and one Cu2+ atom to form distorted OBaSr2Y2Cu octahedra that share corners with two equivalent OBaSr2Y2Cu octahedra and edges with two equivalent OBa2SrY2Cu octahedra. The corner-sharing octahedral tilt angles are 4°. In the fourth O2- site, O2- is bonded to three Ba2+, two Y3+, and one Cu2+ atom to form a mixture of distorted corner and edge-sharing OBa3Y2Cu octahedra. The corner-sharing octahedral tilt angles are 5°. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Ba2+, three Y3+, and one Cu2+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Sr2+, three Y3+, and one Cu2+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Sr2+, three Y3+, and one Cu2+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Ba2+, three Y3+, and one Cu2+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Ba2+, three Y3+, and one Cu2+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, three Y3+, and one Cu2+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Ba2+, three Y3+, and one Cu2+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Sr2+, three Y3+, and one Cu2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2AlFe3 by Materials Project

Y2Fe3Al is Cubic Laves-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Y is bonded in a 12-coordinate geometry to four equivalent Y, nine equivalent Fe, and three equivalent Al atoms. There are one shorter (3.13 Å) and three longer (3.23 Å) Y–Y bond lengths. There are six shorter (3.05 Å) and three longer (3.10 Å) Y–Fe bond lengths. All Y–Al bond lengths are 3.07 Å. Fe is bonded to six equivalent Y, four equivalent Fe, and two equivalent Al atoms to form FeY6Al2Fe4 cuboctahedra that share corners with four equivalent AlY6Fe6 cuboctahedra, corners with fourteen equivalent FeY6Al2Fe4 cuboctahedra, edges with six equivalent FeY6Al2Fe4 cuboctahedra, faces with six equivalent AlY6Fe6 cuboctahedra, and faces with twelve equivalent FeY6Al2Fe4 cuboctahedra. All Fe–Fe bond lengths are 2.61 Å. Both Fe–Al bond lengths are 2.61 Å. Al is bonded to six equivalent Y and six equivalent Fe atoms to form AlY6Fe6 cuboctahedra that share corners with six equivalent AlY6Fe6 cuboctahedra, corners with twelve equivalent FeY6Al2Fe4 cuboctahedra, edges with six equivalent AlY6Fe6 cuboctahedra, and faces with eighteen equivalent FeY6Al2Fe4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y3Pd by Materials Project

Y3Pd is Cementite structured and crystallizes in the orthorhombic Pnma space group. The structure is two-dimensional and consists of two Y3Pd sheets oriented in the (0, 0, 1) direction. there are two inequivalent Y sites. In the first Y site, Y is bonded in a distorted bent 150 degrees geometry to two equivalent Pd atoms. There are one shorter (2.89 Å) and one longer (2.95 Å) Y–Pd bond lengths. In the second Y site, Y is bonded in a 2-coordinate geometry to two equivalent Pd atoms. There are one shorter (2.87 Å) and one longer (2.93 Å) Y–Pd bond lengths. Pd is bonded in a 6-coordinate geometry to six Y atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y5Pt3 by Materials Project

Y5Pt3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded in a 6-coordinate geometry to six equivalent Pt atoms. All Y–Pt bond lengths are 3.06 Å. In the second Y site, Y is bonded in a 5-coordinate geometry to five equivalent Pt atoms. There are a spread of Y–Pt bond distances ranging from 2.91–3.32 Å. Pt is bonded in a 9-coordinate geometry to nine Y atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YTm3(SnPd2)4 by Materials Project

Tm3Y(Pd2Sn)4 is Tungsten-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Tm sites. In the first Tm site, Tm is bonded in a body-centered cubic geometry to eight Pd and six Sn atoms. There are a spread of Tm–Pd bond distances ranging from 2.89–2.94 Å. All Tm–Sn bond lengths are 3.38 Å. In the second Tm site, Tm is bonded in a body-centered cubic geometry to eight Pd and six equivalent Sn atoms. There are two shorter (2.91 Å) and six longer (2.94 Å) Tm–Pd bond lengths. All Tm–Sn bond lengths are 3.38 Å. Y is bonded in a body-centered cubic geometry to eight Pd and six equivalent Sn atoms. All Y–Pd bond lengths are 2.94 Å. All Y–Sn bond lengths are 3.39 Å. There are eight inequivalent Pd sites. In the first Pd site, Pd is bonded in a body-centered cubic geometry to four Tm and four equivalent Sn atoms. There are one shorter (2.92 Å) and three longer (2.94 Å) Pd–Tm bond lengths. There are one shorter (2.91 Å) and three longer (2.94 Å) Pd–Sn bond lengths. In the second Pd site, Pd is bonded in a body-centered cubic geometry to one Tm, three equivalent Y, and four equivalent Sn atoms. The Pd–Tm bond length is 2.89 Å. All Pd–Y bond lengths are 2.94 Å. There are three shorter (2.93 Å) and one longer (2.94 Å) Pd–Sn bond lengths. In the third Pd site, Pd is bonded in a body-centered cubic geometry to four Tm and four equivalent Sn atoms. There are one shorter (2.92 Å) and three longer (2.94 Å) Pd–Tm bond lengths. There are one shorter (2.91 Å) and three longer (2.94 Å) Pd–Sn bond lengths. In the fourth Pd site, Pd is bonded in a body-centered cubic geometry to four Tm and four Sn atoms. All Pd–Tm bond lengths are 2.94 Å. There are one shorter (2.91 Å) and three longer (2.94 Å) Pd–Sn bond lengths. In the fifth Pd site, Pd is bonded in a body-centered cubic geometry to four Tm and four equivalent Sn atoms. There are one shorter (2.91 Å) and three longer (2.94 Å) Pd–Sn bond lengths. In the sixth Pd site, Pd is bonded in a body-centered cubic geometry to one Tm, three equivalent Y, and four equivalent Sn atoms. There are three shorter (2.93 Å) and one longer (2.94 Å) Pd–Sn bond lengths. In the seventh Pd site, Pd is bonded in a body-centered cubic geometry to three equivalent Tm, one Y, and four Sn atoms. There are one shorter (2.89 Å) and three longer (2.94 Å) Pd–Sn bond lengths. In the eighth Pd site, Pd is bonded in a body-centered cubic geometry to four Tm and four Sn atoms. There are one shorter (2.91 Å) and three longer (2.94 Å) Pd–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a distorted body-centered cubic geometry to six Tm and eight Pd atoms. In the second Sn site, Sn is bonded in a distorted body-centered cubic geometry to three equivalent Tm, three equivalent Y, and eight Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y3Mn3Ga2Ge by Materials Project

Y3Mn3GeGa2 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. Y is bonded in a 5-coordinate geometry to six equivalent Mn, three Ga, and two equivalent Ge atoms. There are a spread of Y–Mn bond distances ranging from 3.21–3.31 Å. There are one shorter (2.95 Å) and two longer (2.96 Å) Y–Ga bond lengths. Both Y–Ge bond lengths are 2.95 Å. Mn is bonded in a 12-coordinate geometry to six equivalent Y, two equivalent Mn, three Ga, and one Ge atom. Both Mn–Mn bond lengths are 2.81 Å. There are two shorter (2.63 Å) and one longer (2.79 Å) Mn–Ga bond lengths. The Mn–Ge bond length is 2.76 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded in a 9-coordinate geometry to six equivalent Y and three equivalent Mn atoms. In the second Ga site, Ga is bonded in a distorted q6 geometry to three equivalent Y and six equivalent Mn atoms. Ge is bonded in a 9-coordinate geometry to six equivalent Y and three equivalent Mn atoms.

36 MATERIALS SCIENCE↗
NASA NTRS1997

Impact of Lightning and Convection on Reactive Nitrogen in the Tropical Free Troposphere

Latitudinal distributions of NO, NO(y), O3, CO, CH3I, and H2O mixing ratios at 8.9-12 km were obtained between 30deg N and 1deg S by DC-8 aircraft measurements made in February 1994 during Pacific Exploratory Mission-West B (PEM-West B). Very low NO(y), mixing ratios with a median value of 51 parts per trillion by volume (pptv) were observed at 9.5-12 km at 1deg N-14deg N during two flights made within 3 days. A very low median O3 mixing ratio of 19 parts per billion by volume (ppbv) and high mixing ratios of H2O and CH3I were simultaneously observed, suggesting that the low NO(y), values were probably due to the convective transport of air from the tropical marine boundary layer to this altitude. The median NO(y)/O3 ratio being a factor of 2 smaller than in the air masses in the tropical marine boundary layer might suggest the possibility that the heterogeneous removal of HNO3 during convective transport further reduced NO(y) levels. In addition to the measurements between 9.5 and 12 km, low values of NO(y) and O3 were observed between 4 and 12 km at 1deg N. Divergent wind fields at 200 and 1000 hPa and infrared (IR) cloud images show that there was large scale convection (greater than 1000 km x 1000 km) in the northeast of New Guinea Island centered around Odeg S and 150deg E as part of systematic convective activity of the Intertropical Convergence Zone (ITCZ) and the South Pacific Convergence Zone (SPCZ). This type of large scale convection could have transported air with low levels of NO(y) and O3 to the middle and upper troposphere over a wide area in the tropics. On the other hand, NO mixing ratios of 50-200 pptv and high NQ,/NOY ratios of 0.4-0.6 were observed at 9.5 km between 4deg S and 10deg S. High H2O Mixing ratios of 600-1200 parts per million by volume (ppmv) and low CO mixing ratios of 65 ppbv observed in the air mass indicated that the high NO values were probably due to NO production by lightning. Satellite observations showed relatively frequent lightning flashes over the New Guinea Island for 3 days prior to the aircraft measurements. These results are considered to be consistent with the idea that, in general, marine convection is not accompanied by lightning activity, whereas convection over land is. Because of the large areal extent of the influences from these processes, the convective transport of low NO(y) air and NO production by lightning should play critical roles in controlling the abundance of reactive nitrogen in the equatorial region.

Kawakami, S.↗
DOE OSTI2021

Comparative study of three yttrium organometallic compounds for the stabilization of the cubic phase in YSZ deposited by PE-CVD

In this work, the efficiencies of three organometallic yttrium precursors used to produce YSZ coatings by plasma-enhanced chemical vapor deposition were studied. Yttrium (III) acetylacetonate, Y (acac) 3 , yttrium (III) hexafluoroacetylacetonate, Y (acacF 6 ) 3 , and yttrium (III) tris(2,2,6,6-tetramethyl-3,5-heptanedionate), Y (tmhd) 3 , were used to stabilize the cubic phase in zirconia deposited at temperatures from 500 to 800 °C. Our results showed that at temperatures between 500 and 600 °C, Y (tmhd) 3 appeared to be the most efficient dopant as it introduced the highest concentration of yttria (1–2.7 mol%) with only 6.4–5.6 at.% carbon. However, at 700 and 800 °C, Y (acac) 3 introduced twice as much yttria (8–15 mol%) as Y (tmhd) 3 with almost the same amount of carbon (5.4–3 at.%). Conversely, Y (acacF6)3 was the least efficient as it maintained a low concentration of yttria of around 0.7–1.8 mol% with 3.6–8.2 at.% carbon for all the deposition temperatures. Among these precursors, only Y (acac) 3 surpassed 8 mol% yttria and achieved a fully stabilized cubic phase at 800 °C, with the remaining samples stabilizing only the tetragonal phase. The tetragonal phase was stabilized due to the formation of crystallites of around 10 nm. The observed difference in the efficiency of the three precursors was correlated to important differences in their decomposition behavior as observed by mass spectrometry and thermogravimetry/differential scanning calorimetry.

36 MATERIALS SCIENCE↗
DOE OSTI2021

A density functional theory and neutron diffraction study of the ambient condition properties of sub-stoichiometric yttrium hydride

Several mechanical and thermophysical properties are required as a function of non-stoichiometry for the successful implementation of YH 2-x for nuclear reactor moderator applications. Density functional theory calculations, in combination with neutron diffraction experiments, were used to study the structural and mechanical properties of YH 2-x . Point defect analysis indicated H occupation primarily at the tetrahedral site within an fcc Y sub-lattice, confirming a fluorite YH 2 structure. The small positive formation energy for H vacancies under Y-rich conditions predicted that hypo-stoichiometry is accommodated by Y+YH 2 at ambient conditions and by H vacancies in the YH 2-x single phase that is relevant to high temperatures. Neutron diffraction studies were used to confirm both the occupation of H on tetrahedral sites and the near-stoichiometric composition of the hydride phase in the two-phase Y+YH 2 region of the phase diagram that dominates at room temperature. Energy minimized special-quasirandom-structures of H vacancies were used to calculate lattice parameters, elastic constants, and several other properties as a function of composition for the single phase YH 2-x . The lattice parameter of YH 2-x decreased by only 0.004 Å with increasing H/Y for the range 1.31 ≤ H / Y ≤ 2.0 indicating a negligible effect on lattice parameters due to vacancy formation. In the two-phase region, however, calculations predicted the density of z Y + ( 1 - z ) Y H 2 - x to increase with decreasing H/Y at lower temperatures due to the increased fraction of high-density Y metal. Additionally, for the high temperature single phase, decreasing H/Y reduced the density as a consequence of the lattice expansion associated with vacancy formation. All elastic constants and moduli increased with increasing hydrogen content in single-phase YH 2-x .

36 MATERIALS SCIENCE↗
DOE OSTI2026

Mechanism of Tyrosine-Driven Deprotonation in Photosystem II Revealed by Multiscale Simulations

Photosystem II (PSII) drives light-induced water oxidation via stepwise redox transitions of its oxygen-evolving complex (OEC), a Mn 4 Ca cluster advancing through five intermediate S-states (S 0 –S 4 ). The S 2 → S 3 transition involves a redox event in which a Mn ion donates an electron to the redox-active tyrosine YZ, coupled to deprotonation of an OEC-bound water ligand─yet the underlying coupling mechanism remains unresolved. Time-resolved serial femtosecond crystallography (TR-SFX) has revealed transient electron density shifts near the redox-active tyrosine Y Z , interpreted as sequential oxidation and reduction, with reduction initiating ∼1 μs after excitation and substantially progressed by 30 μs. However, this interpretation conflicts with kinetics from photothermal beam deflection (PBD), time-resolved X-ray absorption spectroscopy (TR-XAS), and electron paramagnetic resonance (EPR), which place electron transfer at 190–400 μs and proton transfer around 30 μs. Here, we reconcile these discrepancies using quantum mechanics/molecular mechanics (QM/MM) and molecular dynamics (MD) simulations. We show that oxidation of P680 and Y Z breaks the symmetry of the nearby hydrogen bonds involving water molecule W4, displacing Y Z and replicating the TR-SFX features of Y Z and Q165 observed at 1 μs. This local perturbation propagates through a hydrogen-bond network, transmitting the electrostatic signal from Y Z to the E65-E312 dyad and triggering redox-coupled deprotonation via the Cl1 channel. By 30 μs, the hydrogen-bond symmetry is restored through deprotonation of W2 (or alternatively W1), reproducing the disappearance of TR-SFX density differences around Y Z and Q165 without requiring Y Z reduction. Our proposed mechanism also gives molecular insights into the O6* density, assigning it to water reorganization rather than a discrete Ca-bound hydroxide species. Here, our results reveal a detailed atomistic mechanism linking Y Z oxidation to long-range proton release and suggest a functional role for the nearby Cl – ion in proton transfer. More broadly, this study underscores the importance of hydrogen-bond dynamics in mediating redox-driven proton transport and demonstrates how integrative simulations can resolve mechanistic ambiguities.

Deprotonation↗