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At least 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Y2MgSi2 by Materials Project

MgY2Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Mg2+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All Mg–Si bond lengths are 2.87 Å. Y3+ is bonded in a distorted hexagonal planar geometry to six equivalent Si4- atoms. There are two shorter (2.95 Å) and four longer (3.03 Å) Y–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to two equivalent Mg2+, six equivalent Y3+, and one Si4- atom. The Si–Si bond length is 2.39 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuAu by Materials Project

AuCu crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Au1- is bonded in a 12-coordinate geometry to six equivalent Cu1+ atoms. All Au–Cu bond lengths are 2.70 Å. Cu1+ is bonded in a distorted hexagonal planar geometry to six equivalent Au1- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Materials Data on La2Sn5 by Materials Project

La2Sn5 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are two inequivalent La sites. In the first La site, La is bonded to two equivalent La and ten Sn atoms to form a mixture of distorted corner, edge, and face-sharing LaLa2Sn10 cuboctahedra. Both La–La bond lengths are 3.27 Å. There are a spread of La–Sn bond distances ranging from 3.37–3.54 Å. In the second La site, La is bonded in a 6-coordinate geometry to four Sn atoms. There are a spread of La–Sn bond distances ranging from 3.13–3.28 Å. There are six inequivalent Sn sites. In the first Sn site, Sn is bonded in a 10-coordinate geometry to six equivalent La and four Sn atoms. There are two shorter (3.27 Å) and two longer (3.31 Å) Sn–Sn bond lengths. In the second Sn site, Sn is bonded in a 12-coordinate geometry to two equivalent La and ten Sn atoms. There are a spread of Sn–Sn bond distances ranging from 3.08–3.47 Å. In the third Sn site, Sn is bonded in a 1-coordinate geometry to three La and four equivalent Sn atoms. In the fourth Sn site, Sn is bonded in a distorted bent 120 degrees geometry to two equivalent La and two equivalent Sn atoms. In the fifth Sn site, Sn is bonded in a hexagonal planar geometry to six Sn atoms. There are two shorter (3.27 Å) and four longer (3.34 Å) Sn–Sn bond lengths. In the sixth Sn site, Sn is bonded in a linear geometry to two equivalent La and four equivalent Sn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nd2MgSi2 by Materials Project

MgNd2Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Mg2+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All Mg–Si bond lengths are 2.97 Å. Nd3+ is bonded in a distorted hexagonal planar geometry to six equivalent Si4- atoms. There are two shorter (3.05 Å) and four longer (3.12 Å) Nd–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to two equivalent Mg2+, six equivalent Nd3+, and one Si4- atom. The Si–Si bond length is 2.40 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2MgSi2 by Materials Project

MgLa2Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Mg2+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All Mg–Si bond lengths are 3.04 Å. La3+ is bonded in a distorted hexagonal planar geometry to six equivalent Si4- atoms. There are two shorter (3.14 Å) and four longer (3.18 Å) La–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to two equivalent Mg2+, six equivalent La3+, and one Si4- atom. The Si–Si bond length is 2.40 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho2MgSi2 by Materials Project

MgHo2Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Mg2+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All Mg–Si bond lengths are 2.85 Å. Ho3+ is bonded in a distorted hexagonal planar geometry to six equivalent Si4- atoms. There are two shorter (2.93 Å) and four longer (3.01 Å) Ho–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to two equivalent Mg2+, six equivalent Ho3+, and one Si4- atom. The Si–Si bond length is 2.38 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb(BMo)2 by Materials Project

Nb(MoB)2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Nb2+ is bonded in a square co-planar geometry to four equivalent B3- atoms. All Nb–B bond lengths are 2.49 Å. Mo2+ is bonded in a distorted hexagonal planar geometry to six equivalent B3- atoms. There are four shorter (2.39 Å) and two longer (2.47 Å) Mo–B bond lengths. B3- is bonded in a 9-coordinate geometry to two equivalent Nb2+, six equivalent Mo2+, and one B3- atom. The B–B bond length is 1.89 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2MgSi2 by Materials Project

MgPr2Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Mg2+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All Mg–Si bond lengths are 2.99 Å. Pr3+ is bonded in a distorted hexagonal planar geometry to six equivalent Si4- atoms. There are two shorter (3.08 Å) and four longer (3.15 Å) Pr–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to two equivalent Mg2+, six equivalent Pr3+, and one Si4- atom. The Si–Si bond length is 2.41 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb2MgSi2 by Materials Project

MgTb2Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Mg2+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All Mg–Si bond lengths are 2.89 Å. Tb3+ is bonded in a distorted hexagonal planar geometry to six equivalent Si4- atoms. There are two shorter (2.96 Å) and four longer (3.04 Å) Tb–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to two equivalent Mg2+, six equivalent Tb3+, and one Si4- atom. The Si–Si bond length is 2.39 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sm2MgSi2 by Materials Project

MgSm2Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Mg2+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All Mg–Si bond lengths are 2.93 Å. Sm3+ is bonded in a distorted hexagonal planar geometry to six equivalent Si4- atoms. There are two shorter (3.02 Å) and four longer (3.08 Å) Sm–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to two equivalent Mg2+, six equivalent Sm3+, and one Si4- atom. The Si–Si bond length is 2.40 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2SnTe3 by Materials Project

K2SnTe3 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Te2- atoms. There are a spread of K–Te bond distances ranging from 3.62–3.76 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six equivalent Te2- atoms. There are a spread of K–Te bond distances ranging from 3.57–3.79 Å. Sn4+ is bonded to four Te2- atoms to form edge-sharing SnTe4 tetrahedra. There are two shorter (2.78 Å) and two longer (2.88 Å) Sn–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 6-coordinate geometry to four equivalent K1+ and two equivalent Sn4+ atoms. In the second Te2- site, Te2- is bonded in a distorted hexagonal planar geometry to five K1+ and one Sn4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Materials Data on Li7Ge12 by Materials Project

Li7Ge12 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are fourteen inequivalent Li sites. In the first Li site, Li is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.69–3.02 Å. In the second Li site, Li is bonded in a 5-coordinate geometry to seven Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.72–3.13 Å. In the third Li site, Li is bonded in a 6-coordinate geometry to seven Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.81–3.15 Å. In the fourth Li site, Li is bonded in a 4-coordinate geometry to seven Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.74–3.05 Å. In the fifth Li site, Li is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.66–2.94 Å. In the sixth Li site, Li is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.65–2.93 Å. In the seventh Li site, Li is bonded in a 4-coordinate geometry to five Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.73–3.05 Å. In the eighth Li site, Li is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.74–3.00 Å. In the ninth Li site, Li is bonded in a 9-coordinate geometry to ten Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.78–3.14 Å. In the tenth Li site, Li is bonded in a 9-coordinate geometry to ten Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.75–3.15 Å. In the eleventh Li site, Li is bonded in a 4-coordinate geometry to seven Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.70–3.22 Å. In the twelfth Li site, Li is bonded in a 4-coordinate geometry to seven Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.69–3.20 Å. In the thirteenth Li site, Li is bonded in a 8-coordinate geometry to nine Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.82–3.21 Å. In the fourteenth Li site, Li is bonded in a 4-coordinate geometry to four Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.57–2.68 Å. There are twenty-four inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to seven Li and three Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.55–2.82 Å. In the second Ge site, Ge is bonded in a 4-coordinate geometry to four Li and three Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.58–2.73 Å. In the third Ge site, Ge is bonded in a 8-coordinate geometry to four Li and four Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.48–2.66 Å. In the fourth Ge site, Ge is bonded in a 8-coordinate geometry to four Li and four Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.49–2.60 Å. In the fifth Ge site, Ge is bonded in a 2-coordinate geometry to four Li and four Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.50–2.65 Å. In the sixth Ge site, Ge is bonded in a 2-coordinate geometry to four Li and four Ge atoms. There are a spread of Ge–Ge bond distances ranging from 2.51–2.66 Å. In the seventh Ge site, Ge is bonded in a 7-coordinate geometry to four Li and three Ge atoms. The Ge–Ge bond length is 2.49 Å. In the eighth Ge site, Ge is bonded in a 7-coordinate geometry to four Li and three Ge atoms. The Ge–Ge bond length is 2.50 Å. In the ninth Ge site, Ge is bonded in a 1-coordinate geometry to three Li and four Ge atoms. There are one shorter (2.49 Å) and one longer (2.54 Å) Ge–Ge bond lengths. In the tenth Ge site, Ge is bonded in a 8-coordinate geometry to four Li and four Ge atoms. There are one shorter (2.52 Å) and one longer (2.56 Å) Ge–Ge bond lengths. In the eleventh Ge site, Ge is bonded in a 7-coordinate geometry to four Li and three Ge atoms. The Ge–Ge bond length is 2.49 Å. In the twelfth Ge site, Ge is bonded in a 6-coordinate geometry to three Li and three Ge atoms. The Ge–Ge bond length is 2.48 Å. In the thirteenth Ge site, Ge is bonded in a 5-coordinate geometry to one Li and four Ge atoms. There are one shorter (2.48 Å) and one longer (2.49 Å) Ge–Ge bond lengths. In the fourteenth Ge site, Ge is bonded in a 5-coordinate geometry to one Li and four Ge atoms. There are one shorter (2.48 Å) and one longer (2.49 Å) Ge–Ge bond lengths. In the fifteenth Ge site, Ge is bonded in a 2-coordinate geometry to two Li and four Ge atoms. There are one shorter (2.55 Å) and one longer (2.56 Å) Ge–Ge bond lengths. In the sixteenth Ge site, Ge is bonded in a 9-coordinate geometry to seven Li and two Ge atoms. The Ge–Ge bond length is 2.55 Å. In the seventeenth Ge site, Ge is bonded in a 9-coordinate geometry to seven Li and two Ge atoms. The Ge–Ge bond length is 2.56 Å. In the eighteenth Ge site, Ge is bonded in a 6-coordinate geometry to two Li and four Ge atoms. The Ge–Ge bond length is 2.51 Å. In the nineteenth Ge site, Ge is bonded in a 6-coordinate geometry to two Li and four Ge atoms. The Ge–Ge bond length is 2.51 Å. In the twentieth Ge site, Ge is bonded in a 7-coordinate geometry to four Li and three Ge atoms. The Ge–Ge bond length is 2.50 Å. In the twenty-first Ge site, Ge is bonded in a 7-coordinate geometry to four Li and three Ge atoms. The Ge–Ge bond length is 2.49 Å. In the twenty-second Ge site, Ge is bonded in a 10-coordinate geometry to seven Li and three Ge atoms. In the twenty-third Ge site, Ge is bonded in a 9-coordinate geometry to six Li and three Ge atoms. In the twenty-fourth Ge site, Ge is bonded in a distorted hexagonal planar geometry to two Li and four Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on B12Pb6O25 by Materials Project

B12Pb6O25 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent B3+ sites. In the first B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There is two shorter (1.49 Å) and two longer (1.50 Å) B–O bond length. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. All B–O bond lengths are 1.38 Å. Pb+2.33+ is bonded in a 3-coordinate geometry to three O2- atoms. There are two shorter (2.34 Å) and one longer (2.36 Å) Pb–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent B3+, one Pb+2.33+, and one O2- atom. The O–O bond length is 2.29 Å. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one B3+ and two equivalent Pb+2.33+ atoms. In the third O2- site, O2- is bonded in a distorted hexagonal planar geometry to six equivalent O2- atoms. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two B3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaU(Te3O8)2 by Materials Project

NaU(Te3O8)2 crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. Na1+ is bonded in a hexagonal planar geometry to six equivalent O2- atoms. All Na–O bond lengths are 2.54 Å. U5+ is bonded to eight O2- atoms to form distorted UO8 hexagonal bipyramids that share edges with six equivalent TeO5 square pyramids. There are two shorter (1.85 Å) and six longer (2.44 Å) U–O bond lengths. Te+4.33+ is bonded to five O2- atoms to form distorted TeO5 square pyramids that share corners with six equivalent TeO5 square pyramids and an edgeedge with one UO8 hexagonal bipyramid. There are a spread of Te–O bond distances ranging from 1.93–2.32 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Na1+ and two equivalent Te+4.33+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one U5+ and two equivalent Te+4.33+ atoms. In the third O2- site, O2- is bonded in a single-bond geometry to one U5+ atom. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to three equivalent Te+4.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La5S7 by Materials Project

La5S7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are seven inequivalent La+2.80+ sites. In the first La+2.80+ site, La+2.80+ is bonded in a distorted body-centered cubic geometry to eight S2- atoms. There are a spread of La–S bond distances ranging from 2.87–3.18 Å. In the second La+2.80+ site, La+2.80+ is bonded in a distorted hexagonal planar geometry to six S2- atoms. There are a spread of La–S bond distances ranging from 2.75–3.27 Å. In the third La+2.80+ site, La+2.80+ is bonded to seven S2- atoms to form LaS7 hexagonal pyramids that share edges with two equivalent LaS7 hexagonal pyramids and faces with two equivalent LaS6 pentagonal pyramids. There are a spread of La–S bond distances ranging from 2.96–3.20 Å. In the fourth La+2.80+ site, La+2.80+ is bonded to six S2- atoms to form distorted LaS6 pentagonal pyramids that share corners with two equivalent LaS6 pentagonal pyramids and faces with two equivalent LaS7 hexagonal pyramids. There are a spread of La–S bond distances ranging from 2.77–2.86 Å. In the fifth La+2.80+ site, La+2.80+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of La–S bond distances ranging from 2.87–3.17 Å. In the sixth La+2.80+ site, La+2.80+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of La–S bond distances ranging from 2.93–3.17 Å. In the seventh La+2.80+ site, La+2.80+ is bonded in a 6-coordinate geometry to six S2- atoms. There are a spread of La–S bond distances ranging from 2.84–2.98 Å. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to five La+2.80+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to five La+2.80+ atoms. In the third S2- site, S2- is bonded in a 5-coordinate geometry to five La+2.80+ atoms. In the fourth S2- site, S2- is bonded to five La+2.80+ atoms to form distorted corner-sharing SLa5 trigonal bipyramids. In the fifth S2- site, S2- is bonded in a 5-coordinate geometry to five La+2.80+ atoms. In the sixth S2- site, S2- is bonded in a 5-coordinate geometry to five La+2.80+ atoms. In the seventh S2- site, S2- is bonded in a 4-coordinate geometry to four La+2.80+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on In2Rh3S2 by Materials Project

Rh3In2S2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Rh is bonded to four In and two equivalent S atoms to form distorted RhIn4S2 octahedra that share corners with two equivalent InRh6S2 hexagonal bipyramids, corners with twelve equivalent RhIn4S2 octahedra, and faces with four equivalent RhIn4S2 octahedra. The corner-sharing octahedra tilt angles range from 0–61°. There are two shorter (2.82 Å) and two longer (2.85 Å) Rh–In bond lengths. Both Rh–S bond lengths are 2.31 Å. There are two inequivalent In sites. In the first In site, In is bonded in a distorted hexagonal planar geometry to six equivalent Rh atoms. In the second In site, In is bonded to six equivalent Rh and two equivalent S atoms to form InRh6S2 hexagonal bipyramids that share corners with six equivalent InRh6S2 hexagonal bipyramids and corners with six equivalent RhIn4S2 octahedra. The corner-sharing octahedral tilt angles are 46°. Both In–S bond lengths are 2.95 Å. S is bonded in a 4-coordinate geometry to three equivalent Rh and one In atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tl2Rh3S2 by Materials Project

Rh3Tl2S2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Rh is bonded to four Tl and two equivalent S atoms to form distorted RhTl4S2 octahedra that share corners with two equivalent TlRh6S2 hexagonal bipyramids, corners with twelve equivalent RhTl4S2 octahedra, and faces with four equivalent RhTl4S2 octahedra. The corner-sharing octahedra tilt angles range from 0–60°. There are two shorter (2.88 Å) and two longer (2.90 Å) Rh–Tl bond lengths. Both Rh–S bond lengths are 2.31 Å. There are two inequivalent Tl sites. In the first Tl site, Tl is bonded in a hexagonal planar geometry to six equivalent Rh atoms. In the second Tl site, Tl is bonded to six equivalent Rh and two equivalent S atoms to form TlRh6S2 hexagonal bipyramids that share corners with six equivalent TlRh6S2 hexagonal bipyramids and corners with six equivalent RhTl4S2 octahedra. The corner-sharing octahedral tilt angles are 46°. Both Tl–S bond lengths are 3.15 Å. S is bonded in a 4-coordinate geometry to three equivalent Rh and one Tl atom.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Effect of hexagonal patterned arrays and defect geometry on the critical current of superconducting films

Understanding the effect of pinning on the vortex dynamics in superconductors is a key factor towards controlling critical current values. Large-scale simulations of vortex dynamics can provide a rational approach to achieve this goal. Here, we use the time-dependent Ginzburg-Landau equations to study thin superconducting films with artificially created pinning centers arranged periodically in hexagonal lattices. We calculate the critical current density for various geometries of the pinning centers—varying their size, strength, and density. Furthermore, we shed light upon the influence of pattern distortion on the magnetic-field-dependent critical current. We compare our result directly with available experimental measurements on patterned molybdenum-germanium films, obtaining good agreement. In conclusion, our results give important systematic insights into the mechanisms of pinning in these artificial pinning landscapes and open a path for tailoring superconducting films with desired critical current behavior.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗