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At least 793 records · Page 44
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on KCuS by Materials Project

KCuS crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. K1+ is bonded to four equivalent S2- atoms to form a mixture of corner and edge-sharing KS4 tetrahedra. There are a spread of K–S bond distances ranging from 3.16–3.22 Å. Cu1+ is bonded in a linear geometry to two equivalent S2- atoms. Both Cu–S bond lengths are 2.16 Å. S2- is bonded to four equivalent K1+ and two equivalent Cu1+ atoms to form a mixture of distorted corner and edge-sharing SK4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–66°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K6Al11Si13Ag5O48 by Materials Project

K6Ag5Al11Si13O48 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded in a 2-coordinate geometry to two O atoms. There are one shorter (2.32 Å) and one longer (2.48 Å) K–O bond lengths. In the second K site, K is bonded in a 3-coordinate geometry to five O atoms. There are a spread of K–O bond distances ranging from 2.46–3.17 Å. In the third K site, K is bonded in a 3-coordinate geometry to five O atoms. There are a spread of K–O bond distances ranging from 2.46–3.12 Å. There are three inequivalent Ag sites. In the first Ag site, Ag is bonded in a trigonal planar geometry to three O atoms. There are a spread of Ag–O bond distances ranging from 2.16–2.51 Å. In the second Ag site, Ag is bonded in a distorted trigonal planar geometry to three O atoms. There are one shorter (2.22 Å) and two longer (2.41 Å) Ag–O bond lengths. In the third Ag site, Ag is bonded in a 4-coordinate geometry to four O atoms. There are two shorter (2.42 Å) and two longer (2.52 Å) Ag–O bond lengths. There are eight inequivalent Al sites. In the first Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra and corners with two SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.71–1.83 Å. In the second Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with three AlO4 tetrahedra. There is one shorter (1.69 Å) and three longer (1.78 Å) Al–O bond length. In the third Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.72–1.78 Å. In the fourth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with three AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.71–1.78 Å. In the fifth Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.71–1.77 Å. In the sixth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra and corners with two SiO4 tetrahedra. There is two shorter (1.73 Å) and two longer (1.82 Å) Al–O bond length. In the seventh Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra and corners with two equivalent SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.67–1.83 Å. In the eighth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra and corners with two equivalent SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.67–1.83 Å. There are eight inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.59–1.68 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.59–1.69 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.58–1.67 Å. In the seventh Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There is two shorter (1.61 Å) and two longer (1.67 Å) Si–O bond length. In the eighth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with three AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.59–1.68 Å. There are thirty inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to one Ag and two Si atoms. In the sixth O site, O is bonded in a distorted bent 150 degrees geometry to one Ag and two Si atoms. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to one Ag and two Si atoms. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to one Ag and two Si atoms. In the ninth O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the tenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the eleventh O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the twelfth O site, O is bonded in a linear geometry to one Al and one Si atom. In the thirteenth O site, O is bonded in a linear geometry to two Si atoms. In the fourteenth O site, O is bonded in a 2-coordinate geometry to one Ag, one Al, and one Si atom. In the fifteenth O site, O is bonded in a distorted trigonal planar geometry to one Ag and two Al atoms. In the sixteenth O site, O is bonded in a 2-coordinate geometry to one K and two Al atoms. In the seventeenth O site, O is bonded in a bent 150 degrees geometry to two Al atoms. In the eighteenth O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the nineteenth O site, O is bonded in a 4-coordinate geometry to one K, one Ag, and two Al atoms. In the twentieth O site, O is bonded to one K, one Ag, and two Al atoms to form distorted edge-sharing OKAl2Ag tetrahedra. In the twenty-first O site, O is bonded in a linear geometry to two equivalent K and two Al atoms. In the twenty-second O site, O is bonded in a 2-coordinate geometry to three K and two Al atoms. In the twenty-third O site, O is bonded in a distorted linear geometry to two equivalent K and two Al atoms. In the twenty-fourth O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent Al atoms. In the twenty-fifth O site, O is bonded in a bent 150 degrees geometry to two Al atoms. In the twenty-sixth O site, O is bonded in a 2-coordinate geometry to one K, one Al, and one Si atom. In the twenty-seventh O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Al, and one Si atom. In the twenty-eighth O site, O is bonded in a distorted bent 150 degrees geometry to one K, one Al, and one Si atom. In the twenty-ninth O site, O is bonded in a 2-coordinate geometry to one K, one Al, and one Si atom. In the thirtieth O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KPd2O3 by Materials Project

KPd2O3 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. K is bonded in a 6-coordinate geometry to six equivalent O atoms. There are three shorter (2.70 Å) and three longer (2.82 Å) K–O bond lengths. There are two inequivalent Pd sites. In the first Pd site, Pd is bonded in an octahedral geometry to six equivalent O atoms. All Pd–O bond lengths are 2.07 Å. In the second Pd site, Pd is bonded in a square co-planar geometry to four equivalent O atoms. All Pd–O bond lengths are 2.06 Å. O is bonded to two equivalent K and three Pd atoms to form a mixture of distorted edge and corner-sharing OK2Pd3 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K14P16Pd9O56 by Materials Project

K14Pd9P16O56 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are nine inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.67–3.25 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.67–3.25 Å. In the third K site, K is bonded in a 6-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.75–3.23 Å. In the fourth K site, K is bonded in a 6-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.74–3.24 Å. In the fifth K site, K is bonded in a 8-coordinate geometry to ten O atoms. There are a spread of K–O bond distances ranging from 2.87–3.40 Å. In the sixth K site, K is bonded in a 6-coordinate geometry to ten O atoms. There are a spread of K–O bond distances ranging from 2.87–3.37 Å. In the seventh K site, K is bonded to six O atoms to form distorted KO6 octahedra that share corners with eight PO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.89–3.02 Å. In the eighth K site, K is bonded in a distorted body-centered cubic geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.79–2.94 Å. In the ninth K site, K is bonded to eight O atoms to form distorted KO8 hexagonal bipyramids that share corners with six PO4 tetrahedra and edges with two equivalent PO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.82–3.17 Å. There are seven inequivalent Pd sites. In the first Pd site, Pd is bonded in a square co-planar geometry to four O atoms. There are two shorter (2.04 Å) and two longer (2.05 Å) Pd–O bond lengths. In the second Pd site, Pd is bonded in a square co-planar geometry to four O atoms. There are two shorter (2.03 Å) and two longer (2.06 Å) Pd–O bond lengths. In the third Pd site, Pd is bonded in a rectangular see-saw-like geometry to four O atoms. There are two shorter (2.04 Å) and two longer (2.06 Å) Pd–O bond lengths. In the fourth Pd site, Pd is bonded in a rectangular see-saw-like geometry to four O atoms. There are a spread of Pd–O bond distances ranging from 2.02–2.07 Å. In the fifth Pd site, Pd is bonded in a square co-planar geometry to four O atoms. All Pd–O bond lengths are 2.04 Å. In the sixth Pd site, Pd is bonded in a rectangular see-saw-like geometry to four O atoms. There are two shorter (2.04 Å) and two longer (2.07 Å) Pd–O bond lengths. In the seventh Pd site, Pd is bonded in a rectangular see-saw-like geometry to four O atoms. There are two shorter (2.03 Å) and two longer (2.08 Å) Pd–O bond lengths. There are eight inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid, a cornercorner with one KO6 octahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 68°. There are a spread of P–O bond distances ranging from 1.50–1.64 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 68°. There are a spread of P–O bond distances ranging from 1.51–1.64 Å. In the third P site, P is bonded to four O atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. In the fourth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid and a cornercorner with one PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. In the fifth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO6 octahedra, a cornercorner with one PO4 tetrahedra, and an edgeedge with one KO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 63°. There are a spread of P–O bond distances ranging from 1.51–1.64 Å. In the sixth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 64°. There are a spread of P–O bond distances ranging from 1.51–1.62 Å. In the seventh P site, P is bonded to four O atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.62 Å. In the eighth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid and a cornercorner with one PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. There are thirty-two inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to two K and two equivalent P atoms. In the second O site, O is bonded in a 2-coordinate geometry to two K and two equivalent P atoms. In the third O site, O is bonded in a distorted bent 120 degrees geometry to one K, one Pd, and one P atom. In the fourth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the fifth O site, O is bonded in a distorted single-bond geometry to four K and one P atom. In the sixth O site, O is bonded in a distorted single-bond geometry to four K and one P atom. In the seventh O site, O is bonded in a 2-coordinate geometry to one K and two equivalent P atoms. In the eighth O site, O is bonded in a bent 120 degrees geometry to two equivalent P atoms. In the ninth O site, O is bonded in a 3-coordinate geometry to one K, one Pd, and one P atom. In the tenth O site, O is bonded in a 1-coordinate geometry to one K, one Pd, and one P atom. In the eleventh O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the twelfth O site, O is bonded in a 2-coordinate geometry to one K, one Pd, and one P atom. In the thirteenth O site, O is bonded in a distorted single-bond geometry to four K and one P atom. In the fourteenth O site, O is bonded in a distorted single-bond geometry to four K and one P atom. In the fifteenth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the sixteenth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the seventeenth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the eighteenth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the nineteenth O site, O is bonded in a 2-coordinate geometry to one K and two equivalent P atoms. In the twentieth O site, O is bonded in a 2-coordinate geometry to one K and two equivalent P atoms. In the twenty-first O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the twenty-second O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the twenty-third O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the twenty-fourth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the twenty-fifth O site, O is bonded in a distorted single-bond geometry to three K and one P atom. In the twenty-sixth O site, O is bonded in a distorted single-bond geometry to three K and one P atom. In the twenty-seventh O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the twenty-eighth O site, O is bonded in a 3-coordinate geometry to one K, one Pd, and one P atom. In the twenty-ninth O site, O is bonded in a bent 120 degrees geometry to two equivalent P atoms. In the thirtieth O site, O is bonded in a distorted bent 120 degrees geometry to one K and two equivalent P atoms. In the thirty-first O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the thirty-second O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K15P16Pd9O56 by Materials Project

K15Pd9P16O56 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are six inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.87–3.29 Å. In the second K site, K is bonded in a body-centered cubic geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.80–2.95 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.69–3.25 Å. In the fourth K site, K is bonded in a 6-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.74–3.25 Å. In the fifth K site, K is bonded to eight O atoms to form distorted KO8 hexagonal bipyramids that share corners with six PO4 tetrahedra and edges with two equivalent PO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.82–3.17 Å. In the sixth K site, K is bonded to six O atoms to form KO6 octahedra that share corners with eight PO4 tetrahedra. There are two shorter (2.90 Å) and four longer (3.01 Å) K–O bond lengths. There are four inequivalent Pd sites. In the first Pd site, Pd is bonded in a rectangular see-saw-like geometry to four O atoms. There are two shorter (2.07 Å) and two longer (2.10 Å) Pd–O bond lengths. In the second Pd site, Pd is bonded in a square co-planar geometry to four O atoms. There are two shorter (2.06 Å) and two longer (2.07 Å) Pd–O bond lengths. In the third Pd site, Pd is bonded in a rectangular see-saw-like geometry to four O atoms. There are a spread of Pd–O bond distances ranging from 2.04–2.08 Å. In the fourth Pd site, Pd is bonded in a square co-planar geometry to four equivalent O atoms. All Pd–O bond lengths are 2.04 Å. There are four inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO6 octahedra, a cornercorner with one PO4 tetrahedra, and an edgeedge with one KO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 63°. There are a spread of P–O bond distances ranging from 1.51–1.64 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid, a cornercorner with one KO6 octahedra, and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 68°. There are a spread of P–O bond distances ranging from 1.50–1.64 Å. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid and a cornercorner with one PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.64 Å. In the fourth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid and a cornercorner with one PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.53–1.63 Å. There are sixteen inequivalent O sites. In the first O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the second O site, O is bonded in a distorted single-bond geometry to four K and one P atom. In the third O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the fourth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the fifth O site, O is bonded in a distorted bent 120 degrees geometry to one K and two equivalent P atoms. In the sixth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the seventh O site, O is bonded in a 1-coordinate geometry to two equivalent K, one Pd, and one P atom. In the eighth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the ninth O site, O is bonded in a distorted single-bond geometry to four K and one P atom. In the tenth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom. In the eleventh O site, O is bonded in a 3-coordinate geometry to one K, one Pd, and one P atom. In the twelfth O site, O is bonded in a 2-coordinate geometry to one K and two equivalent P atoms. In the thirteenth O site, O is bonded in a 2-coordinate geometry to two K and two equivalent P atoms. In the fourteenth O site, O is bonded in a distorted single-bond geometry to two K and one P atom. In the fifteenth O site, O is bonded in a 2-coordinate geometry to one K and two equivalent P atoms. In the sixteenth O site, O is bonded in a 1-coordinate geometry to two K, one Pd, and one P atom.

36 MATERIALS SCIENCE↗
NASA NTRS1993

Spectral evidence for stirring scales and two-dimensional turbulence in the auroral ionosphere

Electric field power spectra from two auroral sounding rocket flights show evidence of a distinct scale size regime for injection of energy into the auroral oval. The signature of this process is a broad plateau in the spectrum, with power law dependences at both shorter and longer scale sizes. We argue that the spectral properties at high k are dominated by processes occurring near the edges of inverted-V electron precipitation regions (auroral arcs). We see no compelling reason to conclude that a linear local plasma instability is occurring but rather, that nonlinear mixing and forward cascade yield the observed velocity field. The spectra of simultaneously observed density irregularities are quite different from those of the electric field, implying that the plasma density does not behave as a passive scalar in the auroral zone during active conditions. At low-k values we show that the rocket spectra are consistent with the power spectra of magnetospheric electric fields measured by the DE, AE-C, and Hilat stallites.

Earle, G. D.↗
DOE OSTI2022

Photonic Crystal Surface Emitting Diode Lasers with λ near 2 µm

Epitaxially regrown electrically pumped photonic crystal surface emitting lasers (PCSELs) operating near 2 µm were designed and fabricated within a III-V-Sb material system. A high-index-contrast photonic crystal layer was incorporated into the laser heterostructures by air-pocket-retaining epitaxial regrowth. Transmission electron microscopy studies confirmed uniform and continuous AlGaAsSb initial growth over the nano-patterned GaSb surface, followed by the development of the air-pockets. The PCSEL threshold current density had a minimal value of ~170 A/cm 2 in the 160–180 K temperature range when the QW gain spectrum aligned with the Γ 2 band edge of the photonic crystal. The devices operated in a continuous wave regime at 160 K. The divergence and polarization of the multimode laser beam emitted from the 200 µm × 200 µm PCSEL aperture were controlled by filamentation.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Rb by Materials Project

RbK3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Rb is bonded to twelve K atoms to form RbK12 cuboctahedra that share corners with six equivalent RbK12 cuboctahedra, corners with twelve KK8Rb4 cuboctahedra, edges with eighteen KK8Rb4 cuboctahedra, faces with eight equivalent RbK12 cuboctahedra, and faces with twelve KK8Rb4 cuboctahedra. All Rb–K bond lengths are 4.80 Å. There are two inequivalent K sites. In the first K site, K is bonded to four equivalent Rb and eight K atoms to form distorted KK8Rb4 cuboctahedra that share corners with four equivalent RbK12 cuboctahedra, corners with fourteen equivalent KK8Rb4 cuboctahedra, edges with six equivalent RbK12 cuboctahedra, edges with twelve KK8Rb4 cuboctahedra, faces with four equivalent RbK12 cuboctahedra, and faces with sixteen KK8Rb4 cuboctahedra. There are a spread of K–K bond distances ranging from 4.76–4.84 Å. In the second K site, K is bonded to four equivalent Rb and eight K atoms to form distorted KK8Rb4 cuboctahedra that share corners with four equivalent RbK12 cuboctahedra, corners with fourteen KK8Rb4 cuboctahedra, edges with six equivalent RbK12 cuboctahedra, edges with twelve KK8Rb4 cuboctahedra, faces with four equivalent RbK12 cuboctahedra, and faces with sixteen KK8Rb4 cuboctahedra. There are one shorter (4.76 Å) and one longer (4.84 Å) K–K bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KICl4 by Materials Project

KICl4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. K is bonded in a 7-coordinate geometry to seven Cl atoms. There are a spread of K–Cl bond distances ranging from 3.13–3.66 Å. I is bonded in a rectangular see-saw-like geometry to four Cl atoms. There are a spread of I–Cl bond distances ranging from 2.48–2.64 Å. There are four inequivalent Cl sites. In the first Cl site, Cl is bonded in a water-like geometry to one K and one I atom. In the second Cl site, Cl is bonded in a distorted T-shaped geometry to two equivalent K and one I atom. In the third Cl site, Cl is bonded in a water-like geometry to one K and one I atom. In the fourth Cl site, Cl is bonded to three equivalent K and one I atom to form a mixture of corner and edge-sharing ClK3I trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KCu2H3(SO5)2 by Materials Project

KCu2H3(SO5)2 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. K1+ is bonded to eight O2- atoms to form distorted KO8 hexagonal bipyramids that share corners with four SO4 tetrahedra, edges with four equivalent CuO6 octahedra, and edges with two SO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.75–2.87 Å. Cu2+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with four SO4 tetrahedra, edges with two equivalent KO8 hexagonal bipyramids, and edges with two equivalent CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.97–2.43 Å. There are three 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 one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.08 Å) and one longer (1.42 Å) H–O bond length. There are two inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two equivalent KO8 hexagonal bipyramids, corners with four equivalent CuO6 octahedra, and an edgeedge with one KO8 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 43–48°. There are a spread of S–O bond distances ranging from 1.46–1.51 Å. In the second S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two equivalent KO8 hexagonal bipyramids, corners with four equivalent CuO6 octahedra, and an edgeedge with one KO8 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 45–49°. There are a spread of S–O bond distances ranging from 1.46–1.51 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Cu2+, and one S6+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Cu2+, and one S6+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Cu2+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted tetrahedral geometry to two equivalent Cu2+ and two H1+ atoms. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to one K1+, two equivalent Cu2+, and one S6+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one K1+, two equivalent Cu2+, and one S6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KO3 by Materials Project

KO3 is Baddeleyite-like structured and crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. K is bonded to seven O atoms to form distorted KO7 pentagonal bipyramids that share corners with eight equivalent KO7 pentagonal bipyramids, corners with two equivalent OK3O tetrahedra, and edges with two equivalent KO7 pentagonal bipyramids. There are a spread of K–O bond distances ranging from 2.81–3.06 Å. There are two inequivalent O sites. In the first O site, O is bonded to three equivalent K and one O atom to form OK3O tetrahedra that share a cornercorner with one KO7 pentagonal bipyramid, corners with twelve equivalent OK3O tetrahedra, and edges with two equivalent OK3O tetrahedra. The O–O bond length is 1.37 Å. In the second O site, O is bonded in a trigonal planar geometry to one K and two equivalent O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K4GeO4 by Materials Project

K4GeO4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.69–3.22 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.68–3.19 Å. In the third K1+ site, K1+ is bonded to five O2- atoms to form distorted KO5 trigonal bipyramids that share corners with two equivalent KO4 tetrahedra, corners with three equivalent GeO4 tetrahedra, an edgeedge with one GeO4 tetrahedra, and edges with two equivalent KO5 trigonal bipyramids. There are a spread of K–O bond distances ranging from 2.64–2.86 Å. In the fourth K1+ site, K1+ is bonded to four O2- atoms to form distorted KO4 tetrahedra that share corners with four equivalent GeO4 tetrahedra, corners with two equivalent KO5 trigonal bipyramids, and edges with two equivalent KO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.62–2.66 Å. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with four equivalent KO4 tetrahedra, corners with three equivalent KO5 trigonal bipyramids, and an edgeedge with one KO5 trigonal bipyramid. There is two shorter (1.80 Å) and two longer (1.81 Å) Ge–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to five K1+ and one Ge4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to five K1+ and one Ge4+ atom. In the third O2- site, O2- is bonded to five K1+ and one Ge4+ atom to form distorted edge-sharing OK5Ge octahedra. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to five K1+ and one Ge4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KLi3 by Materials Project

KLi3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. K is bonded to twelve Li atoms to form a mixture of edge, face, and corner-sharing KLi12 cuboctahedra. There are four shorter (3.46 Å) and eight longer (3.60 Å) K–Li bond lengths. There are two inequivalent Li sites. In the first Li site, Li is bonded in a 4-coordinate geometry to four equivalent K atoms. In the second Li site, Li is bonded in a square co-planar geometry to four equivalent K atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3NbAs2O9 by Materials Project

K3NbAs2O9 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to seven O2- atoms to form distorted KO7 hexagonal pyramids that share corners with two equivalent KO7 hexagonal pyramids, a cornercorner with one AsO4 tetrahedra, edges with three equivalent NbO6 octahedra, and edges with three AsO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.74–2.86 Å. In the second K1+ site, K1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.76–3.41 Å. In the third K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.57–3.30 Å. Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with five AsO4 tetrahedra and edges with three equivalent KO7 hexagonal pyramids. There are a spread of Nb–O bond distances ranging from 1.77–2.42 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent NbO6 octahedra and an edgeedge with one KO7 hexagonal pyramid. The corner-sharing octahedral tilt angles are 32°. There are a spread of As–O bond distances ranging from 1.68–1.77 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share a cornercorner with one KO7 hexagonal pyramid, corners with three equivalent NbO6 octahedra, and edges with two equivalent KO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 32–34°. There are a spread of As–O bond distances ranging from 1.69–1.75 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four K1+ and one As5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to three K1+ and one As5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to four K1+ and one As5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three K1+, one Nb5+, and one As5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two K1+, one Nb5+, and one As5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to four K1+ and one Nb5+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Nb5+, and one As5+ atom.

36 MATERIALS SCIENCE↗
NASA NTRS1994

Infrared photometry and polarimetry of Cygnus X-3

We present photometry and linear polarimetry of Cygnus X-3 at K (2.2 micrometers) obtained over a 5 yr period. Photometry and polarimetry at J, H, and K of nearby field stars is also presented. From an analysis of these data we find: (1) Using the x-ray ephemeris of Kitamoto et al. (ApJ, 384, 263 (1992), including the first and second derivatives of the period, the leading edge of the decline to minimum in the quiescent K light curve has not changed in phase since 1974. The duration of the minimum in the light curve has changed significantly between different epochs, becoming much broader in 1993 than it was previously. (2) In addition to an interstellar polarization component, it is likely Cyg X-3 has an intrinsic polarization component that is variable. The variations in the polarization do not show any diagnostic pattern with orbital phase. A crude analysis of the polarization suggests the intrinsic polarization of Cyg X-3 has a mean position angle of approximately 12 deg, nearly the same as the direction of the expanding radio lobes. This is consistent with circumstellar electrons scattering in an equatorial disk that is perpendicular to the lobe axis. (3) The mean position angle for the interstellar polarization in the direction of Cyg X-3 is 150 deg. This is nearly perpendicular to the axis of interstellar radio scattering seen in the extended (Very Long Baseline Inteferometry (VLBI) images. Since the position angle of interstellar polarization is the same as the projected magnetic field direction, this suggests the interstellar (not circumstellar) scattering must be taking place perpendicular to the interstellar magnetic field lines. (4) Cyg X-3 was observed at K during a flare on 1992 September 30 with a temporal resolution of 6 s. The flaring had rise and fall times of approximately 50 s with peak intensities up to 80 mJy. The flux between individual flare events never dropped to quiescent levels for the duration of our observations (approximately 2000 s).

Jones, Terry Jay↗
DOE OSTI2020

Materials Data on K4MnO4 by Materials Project

K4MnO4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.68–3.21 Å. In the second K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.69–2.91 Å. In the third K1+ site, K1+ is bonded to four O2- atoms to form distorted KO4 trigonal pyramids that share corners with four equivalent MnO4 tetrahedra, corners with two equivalent KO5 trigonal bipyramids, and edges with two equivalent KO4 trigonal pyramids. There are a spread of K–O bond distances ranging from 2.64–2.73 Å. In the fourth K1+ site, K1+ is bonded to five O2- atoms to form distorted KO5 trigonal bipyramids that share corners with three equivalent MnO4 tetrahedra, corners with two equivalent KO4 trigonal pyramids, an edgeedge with one MnO4 tetrahedra, and edges with two equivalent KO5 trigonal bipyramids. There are a spread of K–O bond distances ranging from 2.68–2.84 Å. Mn4+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with three equivalent KO5 trigonal bipyramids, corners with four equivalent KO4 trigonal pyramids, and an edgeedge with one KO5 trigonal bipyramid. There is three shorter (1.83 Å) and one longer (1.84 Å) Mn–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to five K1+ and one Mn4+ atom to form distorted edge-sharing OK5Mn octahedra. In the second O2- site, O2- is bonded in a 1-coordinate geometry to five K1+ and one Mn4+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to five K1+ and one Mn4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to five K1+ and one Mn4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K4ZrO4 by Materials Project

K4ZrO4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.77–2.99 Å. In the second K1+ site, K1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.75–3.22 Å. In the third K1+ site, K1+ is bonded to four O2- atoms to form distorted KO4 trigonal pyramids that share corners with four equivalent ZrO4 tetrahedra, corners with two equivalent KO5 trigonal bipyramids, and edges with two equivalent KO4 trigonal pyramids. There are a spread of K–O bond distances ranging from 2.68–2.72 Å. In the fourth K1+ site, K1+ is bonded to five O2- atoms to form distorted KO5 trigonal bipyramids that share corners with three equivalent ZrO4 tetrahedra, corners with two equivalent KO4 trigonal pyramids, an edgeedge with one ZrO4 tetrahedra, and edges with two equivalent KO5 trigonal bipyramids. There are a spread of K–O bond distances ranging from 2.68–2.93 Å. Zr4+ is bonded to four O2- atoms to form ZrO4 tetrahedra that share corners with three equivalent KO5 trigonal bipyramids, corners with four equivalent KO4 trigonal pyramids, and an edgeedge with one KO5 trigonal bipyramid. There are one shorter (2.00 Å) and three longer (2.01 Å) Zr–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to five K1+ and one Zr4+ atom to form distorted edge-sharing OK5Zr octahedra. In the second O2- site, O2- is bonded in a 6-coordinate geometry to five K1+ and one Zr4+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to five K1+ and one Zr4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to four K1+ and one Zr4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Physics Basis, Optimization, and Control for Integrated 3D Edge Long-pulse Tokamak Scenarios

The aim of this project with international collaborations (PI: J.-K. Park of Princeton Plasma Physics Laboratory) is to develop a unified physics basis and predictive capability for the control of edge-localized modes (ELMs) with optimized non-axisymmetric (3D) fields, by leveraging the unique research capabilities of international KSTAR tokamak in Korea. At the University of California, Irvine, we use a fusion simulation code GTC to study the effects of the 3D magnetic fields (including both magnetic islands and stochastic magnetic field lines) on microturbulence. We focus on the effects of 3D equilibrium on turbulent and neoclassical transport that leads to ELM suppression. During the project period, the UCI team of this collaboration has made significant progress in understanding turbulent transport in 3D geometry including both tokamaks with RMP and stellarators. Four UCI postdoctoral researchers, Drs. Javier Nicolau, Gyungjin Choi, Pengfei Liu, and Xishuo Wei were partially supported by this project and collaborating with the entire project team. We have published 4 journal papers and gave several invited talks. This project advance physics understand of 3D effects on microturbulence, specially effects of magnetic islands. It will contribute to the DOE SciDAC ISEP project in the area of GTC development for general 3D geometry capability, rigorous verification and validation, and readiness for the emerging exascale computing. Through collaborations with computational scientists, the project helps to advance high performance computing in the area of GPU acceleration, linear solver, and data management.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗