Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “W”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,477 records · Page 82
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on KLiWO5 by Materials Project

KLiWO5 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.68–3.24 Å. Li is bonded to four O atoms to form LiO4 tetrahedra that share corners with three equivalent WO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.93–2.09 Å. W is bonded to four O atoms to form WO4 tetrahedra that share corners with three equivalent LiO4 tetrahedra. There are a spread of W–O bond distances ranging from 1.79–1.84 Å. There are five inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to two equivalent K and one W atom. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one K, one Li, and one W atom. In the third O site, O is bonded in a distorted single-bond geometry to two equivalent K and one Li atom. In the fourth O site, O is bonded in a 2-coordinate geometry to one K, one Li, and one W atom. In the fifth O site, O is bonded in a 4-coordinate geometry to two equivalent K, one Li, and one W atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ni6W6C by Materials Project

Ni6W6C crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. W is bonded in a 1-coordinate geometry to six Ni and one C atom. There are a spread of W–Ni bond distances ranging from 2.60–2.73 Å. The W–C bond length is 2.17 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to six equivalent W and six Ni atoms. There are three shorter (2.37 Å) and three longer (2.58 Å) Ni–Ni bond lengths. In the second Ni site, Ni is bonded to six equivalent W and six equivalent Ni atoms to form NiNi6W6 cuboctahedra that share corners with six equivalent CW6 octahedra and faces with six equivalent NiNi6W6 cuboctahedra. The corner-sharing octahedral tilt angles are 45°. C is bonded to six equivalent W atoms to form CW6 octahedra that share corners with twelve equivalent NiNi6W6 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbLiWO5 by Materials Project

RbLiWO5 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Rb is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Rb–O bond distances ranging from 2.77–3.31 Å. Li is bonded to four O atoms to form LiO4 tetrahedra that share corners with three equivalent WO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.94–2.10 Å. W is bonded to four O atoms to form WO4 tetrahedra that share corners with three equivalent LiO4 tetrahedra. There are a spread of W–O bond distances ranging from 1.79–1.85 Å. There are five inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to two equivalent Rb and one W atom. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Rb, one Li, and one W atom. In the third O site, O is bonded in a distorted single-bond geometry to two equivalent Rb and one Li atom. In the fourth O site, O is bonded in a 2-coordinate geometry to one Rb, one Li, and one W atom. In the fifth O site, O is bonded in a 4-coordinate geometry to two equivalent Rb, one Li, and one W atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr8Cu(WO6)3 by Materials Project

Sr8CuW3O18 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are sixteen inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.45–2.68 Å. In the second Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–2.65 Å. In the third Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.47–2.78 Å. In the fourth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 pentagonal pyramids that share corners with three SrO6 octahedra and edges with three WO6 octahedra. The corner-sharing octahedra tilt angles range from 73–75°. There are a spread of Sr–O bond distances ranging from 2.51–2.59 Å. In the fifth Sr2+ site, Sr2+ is bonded to six O2- atoms to form distorted SrO6 pentagonal pyramids that share corners with three SrO6 octahedra and edges with three WO6 octahedra. The corner-sharing octahedral tilt angles are 72°. There are a spread of Sr–O bond distances ranging from 2.51–2.59 Å. In the sixth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–2.76 Å. In the seventh Sr2+ site, Sr2+ is bonded in a 3-coordinate geometry to ten O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–3.27 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 3-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.53–3.19 Å. In the ninth Sr2+ site, Sr2+ is bonded in a 3-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.50–3.00 Å. In the tenth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.50–2.67 Å. In the eleventh Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.43–2.70 Å. In the twelfth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.51–2.69 Å. In the thirteenth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 28–40°. There are a spread of Sr–O bond distances ranging from 2.40–2.53 Å. In the fourteenth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six WO6 octahedra and corners with two equivalent SrO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 26–35°. There are a spread of Sr–O bond distances ranging from 2.41–2.52 Å. In the fifteenth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six WO6 octahedra and a cornercorner with one SrO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 28–33°. There are a spread of Sr–O bond distances ranging from 2.40–2.52 Å. In the sixteenth Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six WO6 octahedra and corners with three SrO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 29–36°. There are a spread of Sr–O bond distances ranging from 2.41–2.51 Å. There are six inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with five SrO6 octahedra. The corner-sharing octahedra tilt angles range from 31–40°. There are a spread of W–O bond distances ranging from 1.90–2.14 Å. In the second W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three SrO6 octahedra. The corner-sharing octahedra tilt angles range from 26–29°. There are a spread of W–O bond distances ranging from 1.89–2.07 Å. In the third W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with four SrO6 octahedra. The corner-sharing octahedra tilt angles range from 28–34°. There are a spread of W–O bond distances ranging from 1.90–2.07 Å. In the fourth W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with five SrO6 octahedra and an edgeedge with one SrO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 30–35°. There are a spread of W–O bond distances ranging from 1.94–1.98 Å. In the fifth W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with four SrO6 octahedra and edges with two equivalent SrO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 28–32°. There are a spread of W–O bond distances ranging from 1.92–1.99 Å. In the sixth W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three SrO6 octahedra and edges with three SrO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 29–33°. There are a spread of W–O bond distances ranging from 1.93–2.00 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of Cu–O bond distances ranging from 1.91–1.96 Å. In the second Cu2+ site, Cu2+ is bonded in a distorted trigonal planar geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.95–2.77 Å. There are thirty-six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to three Sr2+ and one W6+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+, one W6+, and one Cu2+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+, one W6+, and one Cu2+ atom. In the fourth O2- site, O2- is bonded to three Sr2+ and one W6+ atom to form distorted corner-sharing OSr3W trigonal pyramids. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+, one W6+, and one Cu2+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+, one W6+, and one Cu2+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+, one W6+, and one Cu2+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+, one W6+, and one Cu2+ atom. In the ninth O2- site, O2- is bonded to three Sr2+ and one W6+ atom to form distorted corner-sharing OSr3W trigonal pyramids. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to three Sr2+ and one W6+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to three Sr2+ and one W6+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Sr2+ and one W6+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Sr2+ and one W6+ atom. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one W6+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one W6+ atom. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the eighteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Sr2+ and one W6+ atom. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the twentieth O2- site, O2- is bonded to three Sr2+ and one W6+ atom to form a mixture of distorted edge and corner-sharing OSr3W tetrahedra. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the twenty-second O2- site, O2- is bonded to three Sr2+ and one W6+ atom to form a mixture of distorted edge and corner-sharing OSr3W tetrahedra. In the twenty-third O2- site, O2- is bonded to three Sr2+ and one W6+ atom to form a mixture of distorted edge and corner-sharing OSr3W tetrahedra. In the twenty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the twenty-fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the twenty-sixth O2- site, O2- is bonded to three Sr2+ and one W6+ atom to form a mixture of distorted edge and corner-sharing OSr3W tetrahedra. In the twenty-seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the twenty-eighth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the twenty-ninth O2- site, O2- is bonded in a 3-coordinate geometry to three Sr2+, one W6+, and one Cu2+ atom. In the thirtieth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one W6+ atom. In the thirty-first O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the thirty-second O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the thirty-third O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one W6+ atom. In the thirty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the thirty-fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one W6+ atom. In the thirty-sixth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one W6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WSe2)3 by Materials Project

WTe2(WSe2)2MoSe2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoSe2 sheet oriented in the (0, 0, 1) direction; two WSe2 sheets oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoSe2 sheet, Mo6+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing MoSe6 pentagonal pyramids. All Mo–Se bond lengths are 2.56 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In each WSe2 sheet, W+3.33+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing WSe6 pentagonal pyramids. All W–Se bond lengths are 2.56 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the WTe2 sheet, W+3.33+ is bonded to six equivalent Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.72 Å. Te2- is bonded in a 12-coordinate geometry to three equivalent W+3.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TbCu(WO4)2 by Materials Project

TbCu(WO4)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Tb3+ sites. In the first Tb3+ site, Tb3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tb–O bond distances ranging from 2.29–2.84 Å. In the second Tb3+ site, Tb3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Tb–O bond distances ranging from 2.28–2.61 Å. In the third Tb3+ site, Tb3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tb–O bond distances ranging from 2.28–2.72 Å. There are six inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to six O2- atoms to form distorted edge-sharing WO6 octahedra. There are a spread of W–O bond distances ranging from 1.80–2.20 Å. In the second W6+ site, W6+ is bonded to six O2- atoms to form distorted edge-sharing WO6 octahedra. There are a spread of W–O bond distances ranging from 1.80–2.21 Å. In the third W6+ site, W6+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of W–O bond distances ranging from 1.80–2.30 Å. In the fourth W6+ site, W6+ is bonded to six O2- atoms to form distorted edge-sharing WO6 octahedra. There are a spread of W–O bond distances ranging from 1.81–2.21 Å. In the fifth W6+ site, W6+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of W–O bond distances ranging from 1.81–2.28 Å. In the sixth W6+ site, W6+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of W–O bond distances ranging from 1.80–2.26 Å. There are four inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded in a linear geometry to two equivalent O2- atoms. Both Cu–O bond lengths are 1.85 Å. In the second Cu1+ site, Cu1+ is bonded in a distorted square co-planar geometry to four O2- atoms. There are two shorter (1.87 Å) and two longer (2.46 Å) Cu–O bond lengths. In the third Cu1+ site, Cu1+ is bonded in a 4-coordinate geometry to three O2- atoms. There are a spread of Cu–O bond distances ranging from 1.85–2.58 Å. In the fourth Cu1+ site, Cu1+ is bonded in a distorted linear geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.86–2.75 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Tb3+ and two equivalent W6+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Tb3+ and two W6+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Tb3+ and two equivalent W6+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Tb3+ and two W6+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Tb3+ and two W6+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two W6+ and one Cu1+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Tb3+, one W6+, and one Cu1+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Tb3+ and one W6+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Tb3+ and one W6+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Tb3+ and one W6+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one Tb3+, one W6+, and one Cu1+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to one Tb3+, two W6+, and one Cu1+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to two W6+ and one Cu1+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to two W6+ and one Cu1+ atom. In the fifteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Tb3+ and one W6+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Tb3+, one W6+, and one Cu1+ atom. In the seventeenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Tb3+ and two W6+ atoms. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Tb3+ and one W6+ atom. In the nineteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Tb3+, two W6+, and one Cu1+ atom. In the twentieth O2- site, O2- is bonded in a 1-coordinate geometry to one Tb3+, one W6+, and one Cu1+ atom. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to one Tb3+, two W6+, and one Cu1+ atom. In the twenty-second O2- site, O2- is bonded in a bent 120 degrees geometry to one Tb3+ and one W6+ atom. In the twenty-third O2- site, O2- is bonded in a bent 150 degrees geometry to one Tb3+ and one W6+ atom. In the twenty-fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Tb3+ and one W6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on IrW by Materials Project

WIr crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. W is bonded to six equivalent W and six equivalent Ir atoms to form WIr6W6 cuboctahedra that share corners with eighteen equivalent WIr6W6 cuboctahedra, edges with six equivalent WIr6W6 cuboctahedra, edges with twelve equivalent IrIr6W6 cuboctahedra, faces with eight equivalent WIr6W6 cuboctahedra, and faces with twelve equivalent IrIr6W6 cuboctahedra. All W–W bond lengths are 2.81 Å. All W–Ir bond lengths are 2.77 Å. Ir is bonded to six equivalent W and six equivalent Ir atoms to form IrIr6W6 cuboctahedra that share corners with eighteen equivalent IrIr6W6 cuboctahedra, edges with six equivalent IrIr6W6 cuboctahedra, edges with twelve equivalent WIr6W6 cuboctahedra, faces with eight equivalent IrIr6W6 cuboctahedra, and faces with twelve equivalent WIr6W6 cuboctahedra. All Ir–Ir bond lengths are 2.81 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaFe4W by Materials Project

TaWFe4 is Hexagonal Laves-derived structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Ta is bonded in a 1-coordinate geometry to three equivalent Ta, one W, and twelve Fe atoms. All Ta–Ta bond lengths are 2.96 Å. The Ta–W bond length is 2.89 Å. There are a spread of Ta–Fe bond distances ranging from 2.76–2.87 Å. W is bonded in a 7-coordinate geometry to one Ta and twelve Fe atoms. There are a spread of W–Fe bond distances ranging from 2.76–2.80 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to six equivalent Ta and six equivalent Fe atoms to form FeTa6Fe6 cuboctahedra that share corners with twelve equivalent FeTa3Fe6W3 cuboctahedra, edges with six equivalent FeTa6Fe6 cuboctahedra, and faces with twenty FeFe6W6 cuboctahedra. All Fe–Fe bond lengths are 2.42 Å. In the second Fe site, Fe is bonded to six equivalent W and six equivalent Fe atoms to form FeFe6W6 cuboctahedra that share corners with twelve equivalent FeTa3Fe6W3 cuboctahedra, edges with six equivalent FeFe6W6 cuboctahedra, and faces with twenty FeTa6Fe6 cuboctahedra. All Fe–Fe bond lengths are 2.39 Å. In the third Fe site, Fe is bonded to three equivalent Ta, three equivalent W, and six Fe atoms to form FeTa3Fe6W3 cuboctahedra that share corners with eighteen FeTa6Fe6 cuboctahedra, edges with six equivalent FeTa3Fe6W3 cuboctahedra, and faces with eighteen FeTa6Fe6 cuboctahedra. There are two shorter (2.33 Å) and two longer (2.42 Å) Fe–Fe bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on WO5 by Materials Project

WO5 crystallizes in the monoclinic P2/m space group. The structure is two-dimensional and consists of two water molecules and one WO4 sheet oriented in the (0, 1, 0) direction. In the WO4 sheet, W is bonded to six O atoms to form corner-sharing WO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of W–O bond distances ranging from 1.87–2.01 Å. There are four inequivalent O sites. In the first O site, O is bonded in a linear geometry to two equivalent W atoms. In the second O site, O is bonded in a linear geometry to two equivalent W atoms. In the third O site, O is bonded in a linear geometry to two equivalent W atoms. In the fourth O site, O is bonded in a single-bond geometry to one W atom.

36 MATERIALS SCIENCE↗
NASA NTRS1973

Code regenerative clean-up loop transponder for a mu-type ranging system

A loop transponder for regenerating the code of a mu type ranging system is disclosed. It includes a phase locked loop, a code generator, and a loop detector. The function of the phase locked loop is to provide phase lock between a received component wk of the range signal and a replica rafter wk of the received component, provided by the code generator. The code generator also provides a replica of the next component rafter w(w+1). The loop detector responds to wk rafler wk and rafter w(k+1) to determine when the next component w(k+1) is received and controls the code generator to supply w(k+1) to the phase locked loop and to generate a replica rafter w(k+2) of the next component.

Hurd, W. J.↗
NASA NTRS1992

Precipitable water and surface humidity over global oceans from special sensor microwave imager and European Center for Medium Range Weather Forecasts

Global fields of precipitable water W from the special sensor microwave imager were compared with those from the European Center for Medium Range Weather Forecasts (ECMWF) model. They agree over most ocean areas; both data sets capture the two annual cycles examined and the interannual anomalies during an ENSO episode. They show significant differences in the dry air masses over the eastern tropical-subtropical oceans, particularly in the Southern Hemisphere. In these regions, comparisons with radiosonde data indicate that overestimation by the ECMWF model accounts for a large part of the differences. As a check on the W differences, surface-level specific humidity Q derived from W, using a statistical relation, was compared with Q from the ECMWF model. The differences in Q were found to be consistent with the differences in W, indirectly validating the Q-W relation. In both W and Q, SSMI was able to discern clearly the equatorial extension of the tongues of dry air in the eastern tropical ocean, while both ECMWF and climatological fields have reduced spatial gradients and weaker intensity.

Liu, W. T.↗
NASA NTRS1993

Unsteady Flow Simulations in Support of the SSME HEX Turning Vane Cracking Investigation with the ATD HPOTP

Unsteady flow computations are being performed with the P&W (ATD) and the Rocketdyne baseline configurations of the SSME LO2 turbine turnaround duct (TAD) and heat exchanger (HEX). The work is in support of the HEX inner turning vane cracking investigation. Fatigue cracking has occurred during hot firings with the P&W configuration on the HEX inner vane, and it appears the fix will involve changes to the TAD splitter vane position and to the TAD inner wall curvature to reduce the dynamic loading on the inner vane. Unsteady flow computations on the P&W baseline and fix and on the Rocketdyne baseline reference follow steady-flow screening computations done by MSFC/ED32 on several trial configurations arriving at the fix. The P&W TAD inlet velocity profile has a strong radial velocity component that directs the flow toward the inner wall and raises the local velocity a factor of two and the dynamic pressure a factor, of four. The fix is intended to redistribute the flow more evenly across the HEX inner and outer vanes like the Rocketdyne baseline reference. Vane buffeting at frequencies around 4,000 Hz is the leading suspected cause of the problem. Our simulations (work in progress) are being done with the USA 2D axisymmetric code approximating the flow as axisymmetric u+v 2D (axial, u, and radial, v, components only). The HEX coils are included in the model to make sure the fix does not adversely affect the HEX environment. Turbulent kinetic energy, k, levels where k = 1/2 v' rms2 are locally as high as 10,000 ft2/sec2 for the P&W baseline at the engine interface (between the TAD and HEX) at the HEX inner vane location. However, k is less than 8,000 on the HEX outer vane and only about 4,500 on the HEX inner vane for the Rocketdyne baseline. Unsteady turbulence intensity, v'rms/v, and pressure, p', are being computed in the present computations to compare with steady-flow Reynolds-averaged computations where p'rms = const (pk) for overall rms random turbulence from 0.1 to 12,000 Hz frequency. Random overall static, p'rms fluctuations as large as 1.7 psi are estimated from k on the HEX inner vane for the P&W baseline configuration but only about 0.7 psi for the Rocketdyne configuration.

Dougherty, N. S.↗
NASA NTRS2021

Cirrus Cloud Top-of-the-Atmosphere Net Daytime Forcing in the Alaskan Subarctic from Ground-Based MPLNET Monitoring

Cirrus cloud daytime top-of-the-atmosphere radiative forcing (TOA CRF) is estimated for a two-year NASA Micro-Pulse Lidar Network (532 nm; MPLNET) dataset collected at Fairbanks, Alaska. Two-year averaged daytime TOA CRF is estimated at between -1.08 and 0.78 W·m-2 (-0.49 to 1.10 W·m-2 in 2017, and -1.67 to 0.47 W·m-2 in 2018). This subarctic study completes a now trilogy of MPLNET ground-based cloud forcing investigations, following midlatitude and tropical studies by Campbell et al. (2016; C16) at Greenbelt, Maryland and Lolli et al. (2017) at Singapore. C16 hypothesize a global meridional daytime TOA CRF gradient that begins positive at the equator (2.20 – 2.59 W·m-2 over land and -0.46 – 0.42 W·m-2 over ocean at Singapore), becomes neutral in the midlatitudes (0.03 – 0.27 W·m-2 over land in Maryland) and turns negative moving poleward. This study does not completely confirm C16, as values are not found as exclusively negative. Evidence in historical reanalysis data suggests that daytime cirrus forcing in and around the subarctic likely once was exclusively negative. Increasing tropopause heights, inducing higher and colder cirrus, have likely increased regional forcing over the last forty years. We hypothesize that subarctic inter-annual cloud variability is likely a considerable influence on global cirrus cloud forcing sensitivity, given the irregularity of polar versus midlatitude synoptic weather intrusions. This study and hypothesis lays basis for an extrapolation of these MPLNET experiments to satellite-based lidar cirrus cloud datasets.

James R Campbell↗
NASA NTRS2024

Martensitic Phase Transition in Complex NiTi-Based Shape Memory Alloys from First-Principles Calculations

Recent rapid progresses in physics theory and computational power have made it possible to accurately predict the phase transitions and martensitic transition temperatures (MTTs) in shape memory alloys (SMAs) from first principles. However, previously theory and calculations [1-4] were applied only to study highly ordered stoichiometric binary alloys such as NiTi, PdTi and NiHf. Here we report on our recent first-principles investigations [5,6] on Ni 0.5 Ti 0.5-x Hf x and Pd x Ni 0.5-x Ti 0.5 ternaries and off-stoichiometric NiTi, and the predicted martensitic phase transitions in these complex SMAs are in good agreement with experimental findings. In particular, the calculated MTTs for all these compositions are within 100 K compared with the corresponding measured data, and our results also reveal the origin of the striking asymmetry in MTT of the off-stoichiometric NiTi near equiatomic compositions. We will address various techniques to overcome the difficulty encountered in studying ternaries and off-stoichiometic binaries associated with disorder and/or much lowered symmetry. Our theoretical approach is expected to be a broadly applicable and predictive theory for designing complex SMAs with desirable properties. References: [1] J. B. Haskins, A. E. Thompson, and J. W. Lawson, Phys. Rev B 94 , 214110 (2016). [2] J. B. Haskins and J. W. Lawson, J. App. Phys. 121 , 205103 (2017). [3] J. B. Haskins, H. Malmir, S. J. Honrao, L. A. Sandoval, and J. W. Lawson, Acta Materialia 212 , 116872 (2017). [4] Z. Wu, J. W. Lawson, and O. Benafan, Phys. Rev. B 106 , L140102 (2022). [5] Z. Wu, H. Malmir, O. Benafan, and J. W. Lawson, Acta Materialia 261 , 119362 (2023). [6] Z. Wu, J. W. Lawson, and O. Benafan, Phys. Rev. B 108 , L140103 (2023).

Zhigang Wu↗
DOE OSTI2021

Heavily Tungsten–Doped Sodium Thioantimonate Solid–State Electrolytes with Exceptionally Low Activation Energy for Ionic Diffusion

A strategy for modifying the structure of solid-state electrolytes (SSEs) to reduce the cation diffusion activation energy is presented. Two heavily W-doped sodium thioantimonate SSEs, Na 2.895 W 0.3 Sb 0.7 S 4 and Na 2.7 W 0.3 Sb 0.7 S 4 are designed, both exhibiting exceptionally low activation energy and enhanced room temperature (RT) ionic conductivity; 0.09 eV, 24.2 mS/cm and 0.12 eV, 14.5 mS/cm. At –15 °C the Na 2.895 W 0.3 Sb 0.7 S 4 displays a total ionic conductivity of 5.5 mS/cm. Here, the 30 % W content goes far beyond the 10–12 % reported in the prior studies, and results in novel pseudo-cubic or orthorhombic structures. Calculations reveal that these properties result from a combination of multiple diffusion mechanisms, including vacancy defects, strongly correlated modes and excessive Na-ions. An all-solid-state battery (ASSB) using Na 2.895 W 0.3 Sb 0.7 S 4 as the primary SSE and a sodium sulfide (Na 2 S) cathode achieves a reversible capacity of 400 mAh g –1 .

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Heavily Tungsten-Doped Sodium Thioantimonate Solid-State Electrolytes with Exceptionally Low Activation Energy for Ionic Diffusion

A strategy for modifying the structure of solid-state electrolytes (SSEs) to reduce the cation diffusion activation energy is presented. Two heavily W-doped sodium thioantimonate SSEs, Na 2.895 W 0.3 Sb 0.7 S 4 and Na 2.7 W 0.3 Sb 0.7 S 4 are designed, both exhibiting exceptionally low activation energy and enhanced room temperature (RT) ionic conductivity; 0.09 eV, 24.2 mS/cm and 0.12 eV, 14.5 mS/cm. At –15 °C the Na 2.895 W 0.3 Sb 0.7 S 4 displays a total ionic conductivity of 5.5 mS/cm. The 30 % W content goes far beyond the 10–12 % reported in the prior studies, and results in novel pseudo-cubic or orthorhombic structures. Here, calculations reveal that these properties result from a combination of multiple diffusion mechanisms, including vacancy defects, strongly correlated modes and excessive Na-ions. An all-solid-state battery (ASSB) using Na 2.895 W 0.3 Sb 0.7 S 4 as the primary SSE and a sodium sulfide (Na 2 S) cathode achieves a reversible capacity of 400 mAh g –1 .

sodium metal battery (SMB)↗
DOE OSTI2022

Non-local slicing approaches for NNLO QCD in MCFM

We present the implementation of several processes at Next-to-Next-to Leading Order (NNLO) accuracy in QCD in the parton-level Monte Carlo program MCFM. The processes treated are pp → H, W ± , Z, W ± H, ZH, W ± γ, Zγ and γγ and, for the first time in the code, W + W - , W ± Z and ZZ. Decays of the unstable bosons are fully included, resulting in a flexible fully differential Monte Carlo code. The NNLO corrections have been calculated using two non-local slicing approaches, isolating the doubly unresolved region by cutting on the zero-jettiness, $\mathscr{T}_0$, or on q T , the transverse momentum of the colour singlet final-state particles. We find that for most, but not all processes the q T slicing method leads to smaller power corrections for equal computational burden.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2022

Nickel-rich, volatile depleted iron meteorites: Relationships and formation processes

Ungrouped iron meteorites Tishomingo, Willow Grove, and Chinga, and group IVB iron meteorites, are Ni-rich. Similarities include enrichments of 10–100 × CI for some refractory siderophile elements, and equivalent depletions in more volatile siderophile elements. Superimposed on the overall enrichment/depletion trend, certain siderophile elements (P, W, Fe, Mo) are depleted relative to elements of similar volatility. All three ungrouped irons derive from parent bodies formed in the early Solar System. Willow Grove and Chinga are characterized by cosmic ray exposure corrected 182 W/ 184 W consistent with metal-silicate segregation on their parent bodies within 1–3 Myr of Solar System formation, within the age range determined for segregation of magmatic iron meteorite parent bodies, including group IVB irons. Tishomingo is characterized by a younger model age 4–5 Myr subsequent to Solar System formation, reflecting either late stage melting resulting from 26 Al decay, or an impact resetting. The discovery of stishovite in Tishomingo, indicating exposure to a minimum shock pressure of 8–9 GPa, is consistent with the latter. Stishovite in Tishomingo and chromite included in troilite-daubréelite in IVB irons allows oxygen isotopic composition comparison between these meteorites. Different mass independent oxygen isotopic compositions of IVB irons and Tishomingo indicate genetically distinct parent bodies. By contrast, mass independent Mo isotopic compositions overlap within analytical uncertainties, indicating a similar, carbonaceous chondrite (CC) type genetic heritage. Molybdenum and 183 W isotopic data for Chinga and Willow Grove indicate derivation from CC type parent bodies. Willow Grove shares Mo and 183 W isotopic compositions with the Ni-rich South Byron Trio (SBT) grouplet and the Milton pallasite. These Ni-rich meteorites likely formed in the same general nebular environment as other CC planetesimals, likely the outer Solar System. Highly siderophile element (HSE) abundances of Willow Grove and Tishomingo are similar to some IVB meteorites, consistent with formation by moderate degrees of fractional crystallization from initial metallic melts with low S and P, and modestly fractionated HSE. The comparable HSE abundances of Tishomingo and Willow Grove to some IVB irons, yet substantially higher Ni concentrations, indicate formation on parent bodies with lower bulk HSE abundances or HSE concentration in proportionally smaller volumes of metal. HSE abundances in Chinga are considerably lower than in IVB irons, highly fractionated, and processes responsible for these remain elusive. For IVB irons and these ungrouped irons, high temperature condensation likely dominated the enrichment and depletion of the refractory and volatile siderophile elements, respectively. Parent body degassing may have also played a role. Relative depletion of volatile siderophile elements is not, however, a universal feature of high-Ni meteorites. The SBT and Milton pallasite are Ni-rich, but less depleted in the more volatile siderophile elements. Nickel enrichment was likely driven by oxidation of Fe metal during parent body accretion or core segregation. Oxidation of the Tishomingo and Willow Grove parent bodies may have occurred at ~ IW + 1, indicated by relative Mo and W depletions due to metal/water reaction during differentiation. Late-stage reduction, indicated by the presence of Cr-bearing sulfides in Tishomingo and IVB irons, may have resulted from exhaustion of the oxidant.

36 MATERIALS SCIENCE↗