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At least 991 records · Page 55
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Yb3GeO by Materials Project

Yb3GeO crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are three inequivalent Yb sites. In the first Yb site, Yb is bonded in a distorted linear geometry to four equivalent Ge and two equivalent O atoms. There are a spread of Yb–Ge bond distances ranging from 3.06–3.53 Å. Both Yb–O bond lengths are 2.34 Å. In the second Yb site, Yb is bonded in a distorted linear geometry to four equivalent Ge and two equivalent O atoms. There are a spread of Yb–Ge bond distances ranging from 3.11–3.48 Å. There are one shorter (2.33 Å) and one longer (2.34 Å) Yb–O bond lengths. In the third Yb site, Yb is bonded in a distorted linear geometry to four equivalent Ge and two equivalent O atoms. There are a spread of Yb–Ge bond distances ranging from 3.11–3.48 Å. There are one shorter (2.33 Å) and one longer (2.34 Å) Yb–O bond lengths. Ge is bonded to twelve Yb atoms to form distorted GeYb12 cuboctahedra that share corners with twelve equivalent GeYb12 cuboctahedra, faces with six equivalent GeYb12 cuboctahedra, and faces with eight equivalent OYb6 octahedra. O is bonded to six Yb atoms to form OYb6 octahedra that share corners with six equivalent OYb6 octahedra and faces with eight equivalent GeYb12 cuboctahedra. The corner-sharing octahedra tilt angles range from 9–12°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on UH16C4(NO3)2 by Materials Project

UC4H16(NO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two UC4H16(NO3)2 clusters. U4+ is bonded in a distorted linear geometry to four O2- atoms. There are two shorter (1.85 Å) and two longer (2.32 Å) U–O bond lengths. There are two inequivalent C+0.50- sites. In the first C+0.50- site, C+0.50- is bonded to one N3- and three H1+ atoms to form corner-sharing CH3N tetrahedra. The C–N bond length is 1.47 Å. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. In the second C+0.50- site, C+0.50- is bonded to one N3- and three H1+ atoms to form corner-sharing CH3N tetrahedra. The C–N bond length is 1.47 Å. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. N3- is bonded in a distorted trigonal non-coplanar geometry to two C+0.50- and one O2- atom. The N–O bond length is 1.41 Å. There are eight 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 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.74 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C+0.50- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one C+0.50- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one C+0.50- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one C+0.50- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one C+0.50- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one C+0.50- atom. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one U4+ atom. In the second O2- site, O2- is bonded in a water-like geometry to two H1+ atoms. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one U4+, one N3-, and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sc25InIr7 by Materials Project

Sc25Ir7In crystallizes in the cubic Fm-3 space group. The structure is three-dimensional. there are four inequivalent Sc sites. In the first Sc site, Sc is bonded in a linear geometry to two equivalent Ir atoms. Both Sc–Ir bond lengths are 2.71 Å. In the second Sc site, Sc is bonded in a distorted linear geometry to two Ir atoms. There are one shorter (2.76 Å) and one longer (2.98 Å) Sc–Ir bond lengths. In the third Sc site, Sc is bonded to four Ir atoms to form a mixture of distorted edge and corner-sharing ScIr4 tetrahedra. There are one shorter (2.77 Å) and three longer (2.94 Å) Sc–Ir bond lengths. In the fourth Sc site, Sc is bonded in a 1-coordinate geometry to three equivalent Ir and one In atom. There are a spread of Sc–Ir bond distances ranging from 2.69–3.21 Å. The Sc–In bond length is 3.25 Å. There are three inequivalent Ir sites. In the first Ir site, Ir is bonded in a 10-coordinate geometry to ten Sc atoms. In the second Ir site, Ir is bonded in a body-centered cubic geometry to eight equivalent Sc atoms. In the third Ir site, Ir is bonded in a cuboctahedral geometry to twelve equivalent Sc atoms. In is bonded in a cuboctahedral geometry to twelve equivalent Sc atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3SiO by Materials Project

Ca3SiO crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a distorted linear geometry to four equivalent Si4- and two equivalent O2- atoms. There are a spread of Ca–Si bond distances ranging from 3.19–3.51 Å. Both Ca–O bond lengths are 2.37 Å. In the second Ca2+ site, Ca2+ is bonded in a distorted linear geometry to four equivalent Si4- and two equivalent O2- atoms. There are a spread of Ca–Si bond distances ranging from 3.13–3.57 Å. Both Ca–O bond lengths are 2.37 Å. Si4- is bonded in a 12-coordinate geometry to twelve Ca2+ atoms. O2- is bonded to six Ca2+ atoms to form corner-sharing OCa6 octahedra. The corner-sharing octahedra tilt angles range from 8–11°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PbClF by Materials Project

PbFCl crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a distorted linear geometry to four Cl1- and two equivalent F1- atoms. There are a spread of Pb–Cl bond distances ranging from 2.96–3.01 Å. There are one shorter (2.34 Å) and one longer (2.41 Å) Pb–F bond lengths. In the second Pb2+ site, Pb2+ is bonded in a distorted linear geometry to four Cl1- and two equivalent F1- atoms. There are a spread of Pb–Cl bond distances ranging from 2.95–3.01 Å. There are one shorter (2.34 Å) and one longer (2.41 Å) Pb–F bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 8-coordinate geometry to four Pb2+ and four F1- atoms. There are a spread of Cl–F bond distances ranging from 3.34–3.47 Å. In the second Cl1- site, Cl1- is bonded in a 8-coordinate geometry to four Pb2+ and four F1- atoms. There are a spread of Cl–F bond distances ranging from 3.35–3.46 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a linear geometry to two equivalent Pb2+ and four Cl1- atoms. In the second F1- site, F1- is bonded in a linear geometry to two equivalent Pb2+ and four Cl1- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg5Si6 by Materials Project

Mg5Si6 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are ten inequivalent Mg sites. In the first Mg site, Mg is bonded in a distorted linear geometry to two Si atoms. There are one shorter (2.80 Å) and one longer (2.81 Å) Mg–Si bond lengths. In the second Mg site, Mg is bonded in a square co-planar geometry to four Si atoms. All Mg–Si bond lengths are 2.79 Å. In the third Mg site, Mg is bonded in a 5-coordinate geometry to seven Si atoms. There are a spread of Mg–Si bond distances ranging from 2.74–3.15 Å. In the fourth Mg site, Mg is bonded in a 5-coordinate geometry to seven Si atoms. There are a spread of Mg–Si bond distances ranging from 2.74–3.15 Å. In the fifth Mg site, Mg is bonded in a 7-coordinate geometry to seven Si atoms. There are a spread of Mg–Si bond distances ranging from 2.68–2.88 Å. In the sixth Mg site, Mg is bonded in a 7-coordinate geometry to seven Si atoms. There are a spread of Mg–Si bond distances ranging from 2.68–2.88 Å. In the seventh Mg site, Mg is bonded in a 6-coordinate geometry to eight Si atoms. There are a spread of Mg–Si bond distances ranging from 2.88–3.11 Å. In the eighth Mg site, Mg is bonded in a 6-coordinate geometry to eight Si atoms. There are a spread of Mg–Si bond distances ranging from 2.88–3.11 Å. In the ninth Mg site, Mg is bonded in a 9-coordinate geometry to nine Si atoms. There are a spread of Mg–Si bond distances ranging from 2.73–3.02 Å. In the tenth Mg site, Mg is bonded in a 9-coordinate geometry to nine Si atoms. There are a spread of Mg–Si bond distances ranging from 2.73–3.02 Å. There are twelve inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to seven Mg and two Si atoms. There are one shorter (2.45 Å) and one longer (2.56 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 9-coordinate geometry to seven Mg and two Si atoms. The Si–Si bond length is 2.57 Å. In the third Si site, Si is bonded in a 9-coordinate geometry to seven Mg and two Si atoms. There are one shorter (2.41 Å) and one longer (2.49 Å) Si–Si bond lengths. In the fourth Si site, Si is bonded in a 9-coordinate geometry to seven Mg and two Si atoms. The Si–Si bond length is 2.49 Å. In the fifth Si site, Si is bonded in a 3-coordinate geometry to three Mg and four Si atoms. There are a spread of Si–Si bond distances ranging from 2.52–2.80 Å. In the sixth Si site, Si is bonded in a 3-coordinate geometry to three Mg and four Si atoms. There are a spread of Si–Si bond distances ranging from 2.52–2.79 Å. In the seventh Si site, Si is bonded in a 9-coordinate geometry to seven Mg and two Si atoms. There are one shorter (2.42 Å) and one longer (2.46 Å) Si–Si bond lengths. In the eighth Si site, Si is bonded in a 9-coordinate geometry to seven Mg and two Si atoms. There are one shorter (2.42 Å) and one longer (2.46 Å) Si–Si bond lengths. In the ninth Si site, Si is bonded in a 10-coordinate geometry to six Mg and four Si atoms. In the tenth Si site, Si is bonded in a 10-coordinate geometry to six Mg and four Si atoms. In the eleventh Si site, Si is bonded in a 8-coordinate geometry to four Mg and four Si atoms. In the twelfth Si site, Si is bonded in a 8-coordinate geometry to four Mg and four Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgFe2O5 by Materials Project

MgFe2O5 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a distorted linear geometry to five O atoms. There are a spread of Mg–O bond distances ranging from 1.86–2.58 Å. In the second Mg site, Mg is bonded in a distorted square co-planar geometry to four O atoms. There are a spread of Mg–O bond distances ranging from 1.39–2.12 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded in a 2-coordinate geometry to five O atoms. There are a spread of Fe–O bond distances ranging from 1.64–2.43 Å. In the second Fe site, Fe is bonded in a distorted rectangular see-saw-like geometry to four O atoms. There are a spread of Fe–O bond distances ranging from 1.28–2.01 Å. In the third Fe site, Fe is bonded in a 4-coordinate geometry to four O atoms. There are a spread of Fe–O bond distances ranging from 1.32–2.13 Å. In the fourth Fe site, Fe is bonded in a 2-coordinate geometry to four O atoms. There are a spread of Fe–O bond distances ranging from 1.71–2.27 Å. There are ten inequivalent O sites. In the first O site, O is bonded in a 1-coordinate geometry to one Mg and one Fe atom. In the second O site, O is bonded in a 1-coordinate geometry to one Mg and two Fe atoms. In the third O site, O is bonded in a 3-coordinate geometry to one Mg and two Fe atoms. In the fourth O site, O is bonded in a 2-coordinate geometry to one Mg and two Fe atoms. In the fifth O site, O is bonded in a 3-coordinate geometry to one Mg and two Fe atoms. In the sixth O site, O is bonded in a 3-coordinate geometry to one Mg and two Fe atoms. In the seventh O site, O is bonded in a distorted single-bond geometry to one Fe atom. In the eighth O site, O is bonded in a 3-coordinate geometry to one Mg and two Fe atoms. In the ninth O site, O is bonded in a distorted single-bond geometry to one Mg and one Fe atom. In the tenth O site, O is bonded in a 3-coordinate geometry to one Mg and two Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sc50In3Rh13 by Materials Project

Sc50Rh13In3 crystallizes in the cubic Fm-3 space group. The structure is three-dimensional. there are four inequivalent Sc sites. In the first Sc site, Sc is bonded in a linear geometry to two equivalent Rh atoms. Both Sc–Rh bond lengths are 2.74 Å. In the second Sc site, Sc is bonded in a 1-coordinate geometry to three equivalent Rh and one In atom. There are a spread of Sc–Rh bond distances ranging from 2.69–3.21 Å. The Sc–In bond length is 3.25 Å. In the third Sc site, Sc is bonded to four Rh atoms to form a mixture of distorted edge and corner-sharing ScRh4 tetrahedra. There are one shorter (2.78 Å) and three longer (2.99 Å) Sc–Rh bond lengths. In the fourth Sc site, Sc is bonded in a distorted single-bond geometry to one Rh and one In atom. The Sc–Rh bond length is 2.68 Å. The Sc–In bond length is 3.09 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a body-centered cubic geometry to eight equivalent Sc atoms. In the second Rh site, Rh is bonded in a 10-coordinate geometry to ten Sc atoms. There are two inequivalent In sites. In the first In site, In is bonded in a cuboctahedral geometry to twelve equivalent Sc atoms. In the second In site, In is bonded in a cuboctahedral geometry to twelve equivalent Sc atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3SiO by Materials Project

Ca3SiO crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a distorted linear geometry to four equivalent Si4- and two equivalent O2- atoms. There are a spread of Ca–Si bond distances ranging from 3.13–3.56 Å. Both Ca–O bond lengths are 2.37 Å. In the second Ca2+ site, Ca2+ is bonded in a distorted linear geometry to four equivalent Si4- and two equivalent O2- atoms. There are two shorter (3.22 Å) and two longer (3.46 Å) Ca–Si bond lengths. Both Ca–O bond lengths are 2.37 Å. Si4- is bonded to twelve Ca2+ atoms to form distorted SiCa12 cuboctahedra that share corners with twelve equivalent SiCa12 cuboctahedra, faces with six equivalent SiCa12 cuboctahedra, and faces with eight equivalent OCa6 octahedra. O2- is bonded to six Ca2+ atoms to form OCa6 octahedra that share corners with six equivalent OCa6 octahedra and faces with eight equivalent SiCa12 cuboctahedra. The corner-sharing octahedra tilt angles range from 8–11°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CdHgSBr by Materials Project

HgCdSBr crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are two inequivalent Hg1+ sites. In the first Hg1+ site, Hg1+ is bonded in a distorted linear geometry to two equivalent S2- and four Br1- atoms. Both Hg–S bond lengths are 2.41 Å. There are two shorter (3.52 Å) and two longer (3.74 Å) Hg–Br bond lengths. In the second Hg1+ site, Hg1+ is bonded in a 4-coordinate geometry to two equivalent S2- and four Br1- atoms. Both Hg–S bond lengths are 2.43 Å. There are two shorter (3.33 Å) and two longer (3.89 Å) Hg–Br bond lengths. Cd2+ is bonded to two equivalent S2- and four Br1- atoms to form a mixture of distorted edge and corner-sharing CdS2Br4 square pyramids. Both Cd–S bond lengths are 2.81 Å. There are a spread of Cd–Br bond distances ranging from 3.02–3.67 Å. S2- is bonded in a rectangular see-saw-like geometry to two Hg1+ and two equivalent Cd2+ atoms. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 6-coordinate geometry to two equivalent Hg1+ and four equivalent Cd2+ atoms. In the second Br1- site, Br1- is bonded in a body-centered cubic geometry to four equivalent Hg1+ and four equivalent Cd2+ atoms. In the third Br1- site, Br1- is bonded to eight Hg1+ and four equivalent Cd2+ atoms to form distorted face-sharing BrCd4Hg8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SmFe10Mo2N by Materials Project

SmMo2Fe10N crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Sm sites. In the first Sm site, Sm is bonded in a distorted linear geometry to four equivalent Fe and two equivalent N atoms. All Sm–Fe bond lengths are 2.89 Å. Both Sm–N bond lengths are 2.25 Å. In the second Sm site, Sm is bonded in a distorted linear geometry to four equivalent Fe and two equivalent N atoms. All Sm–Fe bond lengths are 2.89 Å. Both Sm–N bond lengths are 2.25 Å. Mo is bonded in a 12-coordinate geometry to one Mo and ten Fe atoms. The Mo–Mo bond length is 2.69 Å. There are a spread of Mo–Fe bond distances ranging from 2.50–2.85 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded in a single-bond geometry to two equivalent Mo, two equivalent Fe, and one N atom. Both Fe–Fe bond lengths are 2.56 Å. The Fe–N bond length is 1.98 Å. In the second Fe site, Fe is bonded in a single-bond geometry to two equivalent Mo, two equivalent Fe, and one N atom. Both Fe–Fe bond lengths are 2.36 Å. The Fe–N bond length is 1.92 Å. In the third Fe site, Fe is bonded in a 6-coordinate geometry to one Sm, one Mo, and four Fe atoms. There are one shorter (2.27 Å) and two longer (2.37 Å) Fe–Fe bond lengths. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to four equivalent Mo and five Fe atoms. The Fe–Fe bond length is 2.24 Å. N is bonded to two equivalent Sm and four Fe atoms to form corner-sharing NSm2Fe4 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ti3Pd5 by Materials Project

Pd5Ti3 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Ti sites. In the first Ti site, Ti is bonded in a distorted linear geometry to two equivalent Pd atoms. Both Ti–Pd bond lengths are 2.83 Å. In the second Ti site, Ti is bonded in a 5-coordinate geometry to five Pd atoms. There are four shorter (2.64 Å) and one longer (2.70 Å) Ti–Pd bond lengths. There are three inequivalent Pd sites. In the first Pd site, Pd is bonded in a 10-coordinate geometry to ten Pd atoms. There are eight shorter (2.77 Å) and two longer (2.97 Å) Pd–Pd bond lengths. In the second Pd site, Pd is bonded in a 10-coordinate geometry to five Ti and one Pd atom. In the third Pd site, Pd is bonded in a distorted single-bond geometry to one Ti and four equivalent Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Bi2Pd3S2 by Materials Project

Pd3Bi2S2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Pd sites. In the first Pd site, Pd is bonded in a distorted linear geometry to four Bi and two equivalent S atoms. There are two shorter (2.94 Å) and two longer (2.95 Å) Pd–Bi bond lengths. Both Pd–S bond lengths are 2.38 Å. In the second Pd site, Pd is bonded in a 2-coordinate geometry to four Bi and two equivalent S atoms. There are a spread of Pd–Bi bond distances ranging from 2.77–3.15 Å. Both Pd–S bond lengths are 2.36 Å. In the third Pd site, Pd is bonded in a 2-coordinate geometry to four Bi and two equivalent S atoms. There are two shorter (2.85 Å) and two longer (3.04 Å) Pd–Bi bond lengths. Both Pd–S bond lengths are 2.37 Å. There are two inequivalent Bi sites. In the first Bi site, Bi is bonded in a 6-coordinate geometry to six Pd atoms. In the second Bi site, Bi is bonded in a 6-coordinate geometry to six Pd atoms. S is bonded in a distorted T-shaped geometry to three Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y8Te3 by Materials Project

Y8Te3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are sixteen inequivalent Y sites. In the first Y site, Y is bonded in a distorted linear geometry to two Te atoms. There are one shorter (3.16 Å) and one longer (3.21 Å) Y–Te bond lengths. In the second Y site, Y is bonded in a distorted L-shaped geometry to two Te atoms. There are one shorter (3.24 Å) and one longer (3.28 Å) Y–Te bond lengths. In the third Y site, Y is bonded in a 3-coordinate geometry to three Te atoms. There are two shorter (3.15 Å) and one longer (3.18 Å) Y–Te bond lengths. In the fourth Y site, Y is bonded in a 4-coordinate geometry to four Te atoms. There are two shorter (3.13 Å) and two longer (3.14 Å) Y–Te bond lengths. In the fifth Y site, Y is bonded in a 4-coordinate geometry to four Te atoms. There are two shorter (3.15 Å) and two longer (3.18 Å) Y–Te bond lengths. In the sixth Y site, Y is bonded in a 3-coordinate geometry to three Te atoms. There are two shorter (3.12 Å) and one longer (3.23 Å) Y–Te bond lengths. In the seventh Y site, Y is bonded in a distorted L-shaped geometry to two equivalent Te atoms. Both Y–Te bond lengths are 3.17 Å. In the eighth Y site, Y is bonded in a distorted L-shaped geometry to two Te atoms. Both Y–Te bond lengths are 3.27 Å. In the ninth Y site, Y is bonded in a 4-coordinate geometry to four Te atoms. All Y–Te bond lengths are 3.14 Å. In the tenth Y site, Y is bonded in a 4-coordinate geometry to four Te atoms. There are two shorter (3.13 Å) and two longer (3.18 Å) Y–Te bond lengths. In the eleventh Y site, Y is bonded in a distorted single-bond geometry to one Te atom. The Y–Te bond length is 3.25 Å. In the twelfth Y site, Y is bonded in a distorted rectangular see-saw-like geometry to four Te atoms. There are two shorter (3.15 Å) and two longer (3.16 Å) Y–Te bond lengths. In the thirteenth Y site, Y is bonded in a distorted single-bond geometry to one Te atom. The Y–Te bond length is 3.22 Å. In the fourteenth Y site, Y is bonded in a 4-coordinate geometry to four Te atoms. There are two shorter (3.15 Å) and two longer (3.17 Å) Y–Te bond lengths. In the fifteenth Y site, Y is bonded to four Te atoms to form distorted corner-sharing YTe4 trigonal pyramids. There are a spread of Y–Te bond distances ranging from 3.16–3.26 Å. In the sixteenth Y site, Y is bonded in a 3-coordinate geometry to three Te atoms. There are one shorter (3.10 Å) and two longer (3.17 Å) Y–Te bond lengths. There are six inequivalent Te sites. In the first Te site, Te is bonded in a 8-coordinate geometry to eight Y atoms. In the second Te site, Te is bonded in a 9-coordinate geometry to eight Y atoms. In the third Te site, Te is bonded in a 8-coordinate geometry to eight Y atoms. In the fourth Te site, Te is bonded to seven Y atoms to form distorted edge-sharing TeY7 pentagonal bipyramids. In the fifth Te site, Te is bonded in a 8-coordinate geometry to eight Y atoms. In the sixth Te site, Te is bonded in a 8-coordinate geometry to eight Y atoms.

36 MATERIALS SCIENCE↗
NASA NTRS1970

Error compensation for hybrid-computer solution of linear differential equations

Z-transform technique compensates for digital transport delay and digital-to-analog hold. Method determines best values for compensation constants in multi-step and Taylor series projections. Technique also provides hybrid-calculation error compared to continuous exact solution, plus system stability properties.

Kemp, N. H.↗
NASA NTRS2014

Understanding Differences in Chemistry Climate Model Projections of Stratospheric Ozone

Chemistry climate models (CCMs) are used to project future evolution of stratospheric ozone as concentrations of ozone-depleting substances (ODSs) decrease and greenhouse gases increase, cooling the stratosphere. CCM projections exhibit not only many common features but also a broad range of values for quantities such as year of ozone return to 1980 and global ozone level at the end of the 21st century. Multiple linear regression is applied to each of 14 CCMs to separate ozone response to ODS concentration change from that due to climate change. We show that the sensitivity of lower stratospheric ozone to chlorine change Delta Ozone/Delta inorganic chlorine is a near-linear function of partitioning of total inorganic chlorine into its reservoirs; both inorganic chlorine and its partitioning are largely controlled by lower stratospheric transport. CCMs with best performance on transport diagnostics agree with observations for chlorine reservoirs and produce similar ozone responses to chlorine change. After 2035, differences in Delta Ozone/Delta inorganic chlorine contribute little to the spread in CCM projections as the anthropogenic contribution to inorganic chlorine becomes unimportant. Differences among upper stratospheric ozone increases due to temperature decreases are explained by differences in ozone sensitivity to temperature change Delta Ozone/Delta T due to different contributions from various ozone loss processes, each with its own temperature dependence. Ozone decrease in the tropical lower stratosphere caused by a projected speedup in the Brewer-Dobson circulation may or may not be balanced by ozone increases in the middle- and high-latitude lower stratosphere and upper troposphere. This balance, or lack thereof, contributes most to the spread in late 21st century projections.

Stratospheric Transport↗
DOE OSTI2021

Shear Assisted Processing and Extrusion (ShAPE) of Aluminum Alloy 7075, 2024, and Al-12.4TM

The most common aluminum alloys utilized in the aerospace industry are 7075 and 2024 due to their high strength-to-weight ratio compared to advanced high strength steels and other aluminum alloys. Despite excellent performance, these aluminum alloys have seen limited use outside of the aerospace industry due in part to high cost. If high-performance aluminum extrusions could be made more cost effectively by eliminating energy intensive process steps typical of conventional extrusion, then numerous opportunities exist for more widespread adoption. A key reason for the high cost of 7075 and 2024 extrusions (25-75% higher than 6061) is their slow extrusion speed. 7075 and 2024 are limited to 2 m/min and 3.5 m/min respectively, in contrast to 6061 which can be extruded at 20–80 m/min. In addition to slow speed, aluminum alloys require numerous thermal treatments throughout the extrusion process including homogenization and pre-heating prior to extrusion, and solution heat treating and artificial aging after extrusion. Each of these steps contribute to the total energy consumed during manufacturing of extruded components. This project investigates the use of ShAPE to improve extrusion speed and reduce, or even eliminate, the typical thermal treatments for high strength aluminum alloys, all while improving material performance. The overarching goal of this project was to demonstrate that Shear Assisted Processing and Extrusion (ShAPE) can manufacture high-performance aluminum alloy tubing with lower manufacturing energy and improved mechanical properties compared to conventional extrusion. Unlike conventional extrusion where the billet is rammed against a stationary die using a strictly linear motion, the ShAPE process superimposes a rotational shear force by spinning the die while the billet is plunged. Compared to conventional linear extrusion, the ShAPE process imparts significantly more strain into the feedstock material, which enables the formation of novel microstructures. These microstructures manifest an array of property and process improvements for extrusion of high-performance aluminum alloys. The following accomplishments were achieved for this project: Extrusion of 7075 at 12.2 meters/min compared to 2 meters/min for conventional extrusion; Elimination of 7075 billet homogenization (430 °C for 20 hours) which is required prior to conventional extrusion; Elimination of 7075 billet pre-heating (400 °C for 1 hour) in a separate furnace which is required prior to conventional extrusion; Achieved 7075-T6with yield strength = 595 MPa, ultimate tensile strength = 531MPa, and elongation = 17.4% for extrusions made from unhomogenized billets. Exceeds the ASTM and ASM standard, and typical industry values; Achieved 7075-T5 (i.e., no solution heat treatment) with yield strength = 588 MPa, ultimate tensile strength = 535 MPa, and elongation = 14.8% for extrusions made from homogenized billets; Extrusion of 2024 at 7.4 meters/min compared to 3.5 meters/min for conventional extrusion; Achieved 2024-T8510 yield strength = 522 MPa, ultimate strength = 510MPa, and elongation = 7.1% for extrusions made from wrought billets. Exceeds the ASTM and ASM standard, and typical industry values; Extrusion of Al-12.4TM high-performance aluminum powder directly into tubing, in a single step, which eliminates process steps typical of powder metallurgy extrusion.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Less Common Topological Phenomena in Bulk Materials

"Prediction and subsequent discovery of topological insulators is considered to be one of the main results in condensed matter physics in the last decades. Not surprisingly, it has received major attention of both researchers and funding agencies. This attention is well-deserved; yet, one cannot but note that nearly all this research revolves about essentially the same concept: electronic excitations with linear dispersion, covering, of course, such diverse and intriguing phenomena as topological insulator, bulk Dirac states (or Weyl, if not spin degenerate), Mayorana fermions. In this project, we will address, mainly, other topological phenomena, such as topologically nontrivial magnetic patterns (as, for instance, topological Hall and related phenomena). Specifically, we propose three interrelated trusts: (1) Time-reversal symmetry breaking nonrelativistic antiferromagnets, called altermagnets. These are materials that break Kramers degeneracy of electronic bands, despite having zero net magnetization by symmetry and being fully collinear, and not necessarily non-centrosymmetric. The corresponding band structure is very similar to the band structure in non-centrosymmetric spin-orbital materials, but materials that we propose to study are distinctly different, first and foremost in the sense that despite sharing many aspects of their electronic properties with the latter, they break the time-reversal symmetry without either spin-orbit coupling or lack of inversion symmetry. (2) Topologically nontrivial magnetic spirals. The PI has been engaged with the experimental group of Dr. Ghimire at GMU investigating Dirac materials with helical magnetism, based on stacked magnetic Kagome layers, with a generic formula of RMn6Sn6. In particular, Y Mn6Sn6 demonstrates a component of the Hall effect that is naturally interpreted in terms of a topological spin texture, as well as linear magnetoresistance. Our calculation identify Dirac states that are robust with respect to the spiral formation, and let us derive an advance mean-field model explaining the observed phase diagram. This model predicted four distinct phases, with very distinct properties, which have now been seen in neutron experiments. The same compound is known to demonstrate topological Hall effect in a particular magnetic phase, and only at elevated temperature. Based on our understanding of the phase diagram, we have worked out a phenomenological theory of a chiral (skyrmionic) response to an external magnetic field, similar to the nematic response to external strain in Fe-based superconductors, which is possible in a centrosymmetric lattice and without interplanar Dzyaloshinskii-Moriya interaction. This phenomenological theory agrees quantitatively with the experiment. It is in our plans to research other similar materials for this effect. (3) Search for 3D analogues of Fe-based superconductors. We want to investigate materials that can be viewed as 3D analogues of FeSe. Specifically, we want materials that are good metals and host antiferromagnetism, which can be suppressed by pressure and generate an s-wave superconductivity, as in Fe-based superconductors. We have in mind some candidates already. This work will proceed in close collaboration with the experimental group of Prof. Nirmal Ghimire in the same department, whose expertise lies in sample making, magnetometry and transport measurements of materials with complex magnetic structures."

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗