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DOE OSTI2020

Materials Data on U3W2O17F2 by Materials Project

U3W2O17F2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent U sites. In the first U site, U is bonded to six O and one F atom to form distorted UO6F pentagonal bipyramids that share corners with three equivalent WO6 octahedra, a cornercorner with one UO6F pentagonal bipyramid, an edgeedge with one WO6 octahedra, and an edgeedge with one UO6F pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 31–40°. There are a spread of U–O bond distances ranging from 1.79–2.47 Å. The U–F bond length is 2.27 Å. In the second U site, U is bonded to five O and two equivalent F atoms to form distorted UO5F2 pentagonal bipyramids that share corners with two equivalent WO6 octahedra and an edgeedge with one UO5F2 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 20°. There are a spread of U–O bond distances ranging from 1.80–2.43 Å. Both U–F bond lengths are 2.33 Å. W is bonded to six O atoms to form distorted WO6 octahedra that share corners with four UO6F pentagonal bipyramids, an edgeedge with one WO6 octahedra, and an edgeedge with one UO6F pentagonal bipyramid. There are a spread of W–O bond distances ranging from 1.81–2.12 Å. There are ten inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one W atom. In the second O site, O is bonded in a single-bond geometry to one U atom. In the third O site, O is bonded in a bent 150 degrees geometry to one U and one W atom. In the fourth O site, O is bonded in a single-bond geometry to one U atom. In the fifth O site, O is bonded in a single-bond geometry to one U atom. In the sixth O site, O is bonded in a single-bond geometry to one U atom. In the seventh O site, O is bonded in a 3-coordinate geometry to two equivalent U and one W atom. In the eighth O site, O is bonded in a single-bond geometry to one U atom. In the ninth O site, O is bonded in a bent 150 degrees geometry to one U and one W atom. In the tenth O site, O is bonded in a distorted trigonal non-coplanar geometry to one U and two equivalent W atoms. There are two inequivalent F sites. In the first F site, F is bonded in a linear geometry to two equivalent U atoms. In the second F site, F is bonded in a bent 120 degrees geometry to two equivalent U atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te4MoW3(SeS)2 by Materials Project

(WTe2)2WSe2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one WSe2 sheet oriented in the (0, 0, 1) direction; and two WTe2 sheets oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.47 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Mo6+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the 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 each WTe2 sheet, W+3.33+ is bonded to six Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.72 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the second Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W+3.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na8Te4W7O36 by Materials Project

Na8W7Te4O36 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are eight inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 1-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.22–2.92 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.30–2.71 Å. In the third Na1+ site, Na1+ is bonded in a 2-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.27–3.01 Å. In the fourth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.50–2.81 Å. In the fifth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.32–3.00 Å. In the sixth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–3.01 Å. In the seventh Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.44–2.82 Å. In the eighth Na1+ site, Na1+ is bonded to seven O2- atoms to form distorted NaO7 pentagonal bipyramids that share corners with three WO6 octahedra and edges with two WO6 octahedra. The corner-sharing octahedra tilt angles range from 27–45°. There are a spread of Na–O bond distances ranging from 2.24–2.73 Å. There are seven inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share corners with two WO6 octahedra and a cornercorner with one NaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 26–39°. There are a spread of W–O bond distances ranging from 1.78–2.22 Å. In the second W6+ site, W6+ is bonded to six O2- atoms to form corner-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 22–41°. There are a spread of W–O bond distances ranging from 1.80–2.13 Å. In the third W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent WO6 octahedra, a cornercorner with one NaO7 pentagonal bipyramid, a cornercorner with one TeO5 trigonal bipyramid, and an edgeedge with one NaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 27–46°. There are a spread of W–O bond distances ranging from 1.80–2.17 Å. In the fourth W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three WO6 octahedra, a cornercorner with one NaO7 pentagonal bipyramid, a cornercorner with one TeO5 trigonal bipyramid, and an edgeedge with one NaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 26–46°. There are a spread of W–O bond distances ranging from 1.79–2.16 Å. In the fifth W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three WO6 octahedra and a cornercorner with one TeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 26–40°. There are a spread of W–O bond distances ranging from 1.80–2.09 Å. In the sixth W6+ site, W6+ is bonded to six O2- atoms to form distorted corner-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 22–41°. There are a spread of W–O bond distances ranging from 1.78–2.20 Å. In the seventh W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three WO6 octahedra and a cornercorner with one TeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 24–40°. There are a spread of W–O bond distances ranging from 1.79–2.10 Å. There are four inequivalent Te+5.50+ sites. In the first Te+5.50+ site, Te+5.50+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.84–2.74 Å. In the second Te+5.50+ site, Te+5.50+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–1.93 Å. In the third Te+5.50+ site, Te+5.50+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.90 Å) and two longer (1.91 Å) Te–O bond length. In the fourth Te+5.50+ site, Te+5.50+ is bonded to five O2- atoms to form TeO5 trigonal bipyramids that share corners with four WO6 octahedra. The corner-sharing octahedra tilt angles range from 33–55°. There are a spread of Te–O bond distances ranging from 1.82–2.00 Å. There are thirty-six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Na1+ and one W6+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one W6+, and one Te+5.50+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te+5.50+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and two W6+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and one W6+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two W6+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te+5.50+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one W6+, and one Te+5.50+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and one W6+ atom. In the tenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to two Na1+ and one Te+5.50+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Na1+ and one O2- atom. The O–O bond length is 1.23 Å. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and one W6+ atom. In the thirteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one W6+ and one Te+5.50+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one W6+, and one Te+5.50+ atom. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one W6+, and one Te+5.50+ atom. In the sixteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and two W6+ atoms. In the seventeenth O2- site, O2- is bonded in a bent 150 degrees geometry to two W6+ atoms. In the eighteenth O2- site, O2- is bonded in a trigonal non-coplanar geometry to two Na1+ and one Te+5.50+ atom. In the nineteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and two W6+ atoms. In the twentieth O2- site, O2- is bonded in a bent 150 degrees geometry to two W6+ atoms. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te+5.50+ atom. In the twenty-second O2- site, O2- is bonded to three Na1+ and one W6+ atom to form distorted edge-sharing ONa3W tetrahedra. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one W6+ atom. In the twenty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te+5.50+ atom. In the twenty-fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two W6+ atoms. In the twenty-sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te+5.50+ atom. In the twenty-seventh O2- site, O2- is bonded to three Na1+ and one W6+ atom to form distorted edge-sharing ONa3W trigonal pyramids. In the twenty-eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and one W6+ atom. In the twenty-ninth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+, one W6+, and one Te+5.50+ atom. In the thirtieth O2- site, O2- is bonded in a single-bond geometry to one O2- atom. In the thirty-first O2- site, O2- is bonded in a 3-coordinate geometry to two Na1+, one W6+, and one Te+5.50+ atom. In the thirty-second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one W6+, and one Te+5.50+ atom. In the thirty-third O2- site, O2- is bonded in a bent 150 degrees geometry to two W6+ atoms. In the thirty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+ and two W6+ atoms. In the thirty-fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Na1+ and two W6+ atoms. In the thirty-sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one W6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K15W7N19 by Materials Project

K15W7N19 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are sixteen inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.77–3.45 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.76–3.25 Å. In the third K1+ site, K1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.80–3.09 Å. In the fourth K1+ site, K1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.67–2.98 Å. In the fifth K1+ site, K1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.68–3.00 Å. In the sixth K1+ site, K1+ is bonded in a 3-coordinate geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.74–3.33 Å. In the seventh K1+ site, K1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.77–3.15 Å. In the eighth K1+ site, K1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of K–N bond distances ranging from 2.74–3.25 Å. In the ninth K1+ site, K1+ is bonded in a 3-coordinate geometry to five N3- atoms. There are a spread of K–N bond distances ranging from 2.78–3.36 Å. In the tenth K1+ site, K1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.88–3.04 Å. In the eleventh K1+ site, K1+ is bonded in a distorted rectangular see-saw-like geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.67–3.01 Å. In the twelfth K1+ site, K1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of K–N bond distances ranging from 2.79–3.39 Å. In the thirteenth K1+ site, K1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.71–3.05 Å. In the fourteenth K1+ site, K1+ is bonded in a 4-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.63–3.35 Å. In the fifteenth K1+ site, K1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.84–3.42 Å. In the sixteenth K1+ site, K1+ is bonded in a hexagonal planar geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 3.05–3.28 Å. There are seven inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.80–1.94 Å. In the second W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.80–1.94 Å. In the third W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.80–1.94 Å. In the fourth W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.82–1.97 Å. In the fifth W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.79–1.93 Å. In the sixth W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.82–1.98 Å. In the seventh W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.82–1.97 Å. There are nineteen inequivalent N3- sites. In the first N3- site, N3- is bonded in a 6-coordinate geometry to five K1+ and one W6+ atom. In the second N3- site, N3- is bonded in a 2-coordinate geometry to four K1+ and two W6+ atoms. In the third N3- site, N3- is bonded to four K1+ and one W6+ atom to form distorted corner-sharing NK4W trigonal bipyramids. In the fourth N3- site, N3- is bonded in a 4-coordinate geometry to two K1+ and two W6+ atoms. In the fifth N3- site, N3- is bonded in a 2-coordinate geometry to three K1+ and two W6+ atoms. In the sixth N3- site, N3- is bonded to four K1+ and one W6+ atom to form a mixture of distorted corner and edge-sharing NK4W trigonal bipyramids. In the seventh N3- site, N3- is bonded in a 1-coordinate geometry to four K1+ and one W6+ atom. In the eighth N3- site, N3- is bonded in a 6-coordinate geometry to four K1+ and two W6+ atoms. In the ninth N3- site, N3- is bonded in a 1-coordinate geometry to five K1+ and one W6+ atom. In the tenth N3- site, N3- is bonded in a 6-coordinate geometry to five K1+ and one W6+ atom. In the eleventh N3- site, N3- is bonded in a 2-coordinate geometry to three K1+ and two W6+ atoms. In the twelfth N3- site, N3- is bonded in a 4-coordinate geometry to four K1+ and one W6+ atom. In the thirteenth N3- site, N3- is bonded in a 2-coordinate geometry to three K1+ and two W6+ atoms. In the fourteenth N3- site, N3- is bonded in a 6-coordinate geometry to four K1+ and two W6+ atoms. In the fifteenth N3- site, N3- is bonded in a 6-coordinate geometry to five K1+ and one W6+ atom. In the sixteenth N3- site, N3- is bonded in a 4-coordinate geometry to three K1+ and two W6+ atoms. In the seventeenth N3- site, N3- is bonded in a 2-coordinate geometry to two K1+ and two W6+ atoms. In the eighteenth N3- site, N3- is bonded in a 6-coordinate geometry to five K1+ and one W6+ atom. In the nineteenth N3- site, N3- is bonded in a 5-coordinate geometry to four K1+ and one W6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on EuWO5 by Materials Project

EuWO5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Eu is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Eu–O bond distances ranging from 2.36–2.54 Å. W is bonded in a distorted trigonal bipyramidal geometry to five O atoms. There are a spread of W–O bond distances ranging from 1.80–2.14 Å. There are five inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to two equivalent Eu and one W atom. In the second O site, O is bonded in a distorted trigonal non-coplanar geometry to two equivalent Eu and one W atom. In the third O site, O is bonded in a 3-coordinate geometry to two equivalent Eu and one W atom. In the fourth O site, O is bonded in a linear geometry to one Eu and one W atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Eu and one W atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re2W by Materials Project

WRe2 is Hexagonal Laves structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. W is bonded in a 12-coordinate geometry to four equivalent W and twelve Re atoms. There are one shorter (3.07 Å) and three longer (3.17 Å) W–W bond lengths. There are six shorter (2.99 Å) and six longer (3.02 Å) W–Re bond lengths. There are two inequivalent Re sites. In the first Re site, Re is bonded to six equivalent W and six equivalent Re atoms to form a mixture of face, edge, and corner-sharing ReRe6W6 cuboctahedra. All Re–Re bond lengths are 2.60 Å. In the second Re site, Re is bonded to six equivalent W and six Re atoms to form a mixture of face, edge, and corner-sharing ReRe6W6 cuboctahedra. There are two shorter (2.48 Å) and two longer (2.66 Å) Re–Re bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SmW4S2NO8 by Materials Project

SmW4NS2O8 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of two SmW4NS2O8 sheets oriented in the (0, 1, 0) direction. Sm3+ is bonded to six O2- atoms to form distorted SmO6 pentagonal pyramids that share corners with two SO4 tetrahedra and edges with two SO4 tetrahedra. There are a spread of Sm–O bond distances ranging from 2.29–2.59 Å. There are four inequivalent W5+ sites. In the first W5+ site, W5+ is bonded in an L-shaped geometry to one N3- and one O2- atom. The W–N bond length is 2.11 Å. The W–O bond length is 2.36 Å. In the second W5+ site, W5+ is bonded in a single-bond geometry to one O2- atom. The W–O bond length is 2.34 Å. In the third W5+ site, W5+ is bonded in a bent 150 degrees geometry to one N3- and one O2- atom. The W–N bond length is 1.86 Å. The W–O bond length is 2.24 Å. In the fourth W5+ site, W5+ is bonded in an L-shaped geometry to one N3- and one O2- atom. The W–N bond length is 2.31 Å. The W–O bond length is 2.24 Å. N3- is bonded in a distorted T-shaped geometry to three W5+ atoms. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one SmO6 pentagonal pyramid and an edgeedge with one SmO6 pentagonal pyramid. There are a spread of S–O bond distances ranging from 1.46–1.54 Å. In the second S2- site, S2- is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one SmO6 pentagonal pyramid and an edgeedge with one SmO6 pentagonal pyramid. There are a spread of S–O bond distances ranging from 1.45–1.52 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Sm3+, one W5+, and one S2- atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Sm3+ and one S2- atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two W5+ and one S2- atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Sm3+ and one S2- atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sm3+ and one S2- atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sm3+ and one S2- atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to one Sm3+ and one S2- atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one W5+ and one S2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sn2W3Cl14 by Materials Project

W3Sn2Cl14 crystallizes in the hexagonal P6_3 space group. The structure is two-dimensional and consists of two W3Sn2Cl14 sheets oriented in the (0, 0, 1) direction. W+3.33+ is bonded to six Cl1- atoms to form WCl6 octahedra that share a cornercorner with one SnCl4 trigonal pyramid and edges with two equivalent WCl6 octahedra. There are a spread of W–Cl bond distances ranging from 2.41–2.50 Å. There are two inequivalent Sn2+ sites. In the first Sn2+ site, Sn2+ is bonded in a 6-coordinate geometry to six Cl1- atoms. There are three shorter (2.72 Å) and three longer (3.13 Å) Sn–Cl bond lengths. In the second Sn2+ site, Sn2+ is bonded to four Cl1- atoms to form distorted SnCl4 trigonal pyramids that share corners with three equivalent WCl6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are one shorter (2.42 Å) and three longer (3.06 Å) Sn–Cl bond lengths. There are six inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Sn2+ atom. In the second Cl1- site, Cl1- is bonded in a 12-coordinate geometry to three equivalent W+3.33+ atoms. In the third Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two equivalent W+3.33+ atoms. In the fourth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to one W+3.33+ and one Sn2+ atom. In the fifth Cl1- site, Cl1- is bonded in a water-like geometry to one W+3.33+ and one Sn2+ atom. In the sixth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one W+3.33+ and one Sn2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Rb15W7N19 by Materials Project

Rb15W7N19 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are sixteen inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Rb–N bond distances ranging from 2.85–3.19 Å. In the second Rb1+ site, Rb1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Rb–N bond distances ranging from 2.91–3.41 Å. In the third Rb1+ site, Rb1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of Rb–N bond distances ranging from 2.89–3.34 Å. In the fourth Rb1+ site, Rb1+ is bonded in a 1-coordinate geometry to six N3- atoms. There are a spread of Rb–N bond distances ranging from 2.79–3.50 Å. In the fifth Rb1+ site, Rb1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of Rb–N bond distances ranging from 2.82–3.12 Å. In the sixth Rb1+ site, Rb1+ is bonded in a 3-coordinate geometry to four N3- atoms. There are a spread of Rb–N bond distances ranging from 2.93–3.47 Å. In the seventh Rb1+ site, Rb1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Rb–N bond distances ranging from 2.92–3.16 Å. In the eighth Rb1+ site, Rb1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of Rb–N bond distances ranging from 2.82–3.18 Å. In the ninth Rb1+ site, Rb1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Rb–N bond distances ranging from 2.93–3.57 Å. In the tenth Rb1+ site, Rb1+ is bonded in a 6-coordinate geometry to five N3- atoms. There are a spread of Rb–N bond distances ranging from 3.01–3.36 Å. In the eleventh Rb1+ site, Rb1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of Rb–N bond distances ranging from 2.78–3.18 Å. In the twelfth Rb1+ site, Rb1+ is bonded in a 1-coordinate geometry to seven N3- atoms. There are a spread of Rb–N bond distances ranging from 2.93–3.55 Å. In the thirteenth Rb1+ site, Rb1+ is bonded in a 3-coordinate geometry to four N3- atoms. There are a spread of Rb–N bond distances ranging from 2.81–3.30 Å. In the fourteenth Rb1+ site, Rb1+ is bonded in a 4-coordinate geometry to five N3- atoms. There are a spread of Rb–N bond distances ranging from 2.72–3.43 Å. In the fifteenth Rb1+ site, Rb1+ is bonded in a hexagonal planar geometry to six N3- atoms. There are two shorter (3.04 Å) and four longer (3.26 Å) Rb–N bond lengths. In the sixteenth Rb1+ site, Rb1+ is bonded in a hexagonal planar geometry to six N3- atoms. There are a spread of Rb–N bond distances ranging from 3.08–3.29 Å. There are seven inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.80–1.94 Å. In the second W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.80–1.95 Å. In the third W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.80–1.95 Å. In the fourth W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.82–1.98 Å. In the fifth W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.79–1.94 Å. In the sixth W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.82–1.98 Å. In the seventh W6+ site, W6+ is bonded to four N3- atoms to form corner-sharing WN4 tetrahedra. There are a spread of W–N bond distances ranging from 1.83–1.98 Å. There are nineteen inequivalent N3- sites. In the first N3- site, N3- is bonded in a 1-coordinate geometry to five Rb1+ and one W6+ atom. In the second N3- site, N3- is bonded in a distorted linear geometry to three Rb1+ and two W6+ atoms. In the third N3- site, N3- is bonded in a 1-coordinate geometry to five Rb1+ and one W6+ atom. In the fourth N3- site, N3- is bonded in a 3-coordinate geometry to three Rb1+ and two W6+ atoms. In the fifth N3- site, N3- is bonded in a 2-coordinate geometry to four Rb1+ and two W6+ atoms. In the sixth N3- site, N3- is bonded to four Rb1+ and one W6+ atom to form distorted edge-sharing NRb4W trigonal bipyramids. In the seventh N3- site, N3- is bonded in a 1-coordinate geometry to six Rb1+ and one W6+ atom. In the eighth N3- site, N3- is bonded in a 2-coordinate geometry to four Rb1+ and two W6+ atoms. In the ninth N3- site, N3- is bonded in a 1-coordinate geometry to five Rb1+ and one W6+ atom. In the tenth N3- site, N3- is bonded in a 6-coordinate geometry to five Rb1+ and one W6+ atom. In the eleventh N3- site, N3- is bonded in a 2-coordinate geometry to three Rb1+ and two W6+ atoms. In the twelfth N3- site, N3- is bonded in a 5-coordinate geometry to four Rb1+ and one W6+ atom. In the thirteenth N3- site, N3- is bonded in a 2-coordinate geometry to two Rb1+ and two W6+ atoms. In the fourteenth N3- site, N3- is bonded in a 2-coordinate geometry to four Rb1+ and two W6+ atoms. In the fifteenth N3- site, N3- is bonded in a 1-coordinate geometry to five Rb1+ and one W6+ atom. In the sixteenth N3- site, N3- is bonded in a 2-coordinate geometry to three Rb1+ and two W6+ atoms. In the seventeenth N3- site, N3- is bonded in a 2-coordinate geometry to two Rb1+ and two W6+ atoms. In the eighteenth N3- site, N3- is bonded in a 1-coordinate geometry to five Rb1+ and one W6+ atom. In the nineteenth N3- site, N3- is bonded in a 5-coordinate geometry to four Rb1+ and one W6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2022

An “Eddy β-Spiral” mechanism for vertical velocity dipole patterns of isolated oceanic mesoscale eddies

Oceanic eddies accompanied by a significant vertical velocity ( w ) are known to be of great importance for the vertical transport of various climatically, biologically or biogeochemically relevant properties. Using quasi-geostrophic w -thinking to extend the classic “ β -spiral” w -theory for gyre circulations to isolated and nearly symmetric oceanic mesoscale eddies, we propose that their w motion will be dominated by a strong east-west dipole pattern with deep ocean penetrations. Contrasting numerical simulations of idealized isolated eddies together with w -equation diagnostics confirm that the w -dipole is indeed dominated by the “eddy β -spiral” mechanism in the β -plane simulation, whereas this w -dipole expectedly disappears in the f -plane simulation. Analyses of relatively isolated warm and cold eddy examples show good agreement with the proposed mechanism. Our studies further clarify eddy vertical motions, have implications for ocean mixing and vertical transport, and inspire further studies.

58 GEOSCIENCES↗
DOE OSTI2024

The Dark Energy Survey: Cosmology Results with ∼1500 New High-redshift Type Ia Supernovae Using the Full 5 yr Data Set

Abstract We present cosmological constraints from the sample of Type Ia supernovae (SNe Ia) discovered and measured during the full 5 yr of the Dark Energy Survey (DES) SN program. In contrast to most previous cosmological samples, in which SNe are classified based on their spectra, we classify the DES SNe using a machine learning algorithm applied to their light curves in four photometric bands. Spectroscopic redshifts are acquired from a dedicated follow-up survey of the host galaxies. After accounting for the likelihood of each SN being an SN Ia, we find 1635 DES SNe in the redshift range 0.10 < z < 1.13 that pass quality selection criteria sufficient to constrain cosmological parameters. This quintuples the number of high-quality z > 0.5 SNe compared to the previous leading compilation of Pantheon+ and results in the tightest cosmological constraints achieved by any SN data set to date. To derive cosmological constraints, we combine the DES SN data with a high-quality external low-redshift sample consisting of 194 SNe Ia spanning 0.025 < z < 0.10. Using SN data alone and including systematic uncertainties, we find Ω M = 0.352 ± 0.017 in flat ΛCDM. SN data alone now require acceleration ( q 0 < 0 in ΛCDM) with over 5 σ confidence. We find ( Ω M , w ) = ( 0.264 − 0.096 + 0.074 , − 0.80 − 0.16 + 0.14 ) in flat w CDM. For flat w 0 w a CDM, we find ( Ω M , w 0 , w a ) = ( 0.495 − 0.043 + 0.033 , − 0.36 − 0.30 + 0.36 , − 8.8 − 4.5 + 3.7 ) , consistent with a constant equation of state to within ∼2 σ . Including Planck cosmic microwave background, Sloan Digital Sky Survey baryon acoustic oscillation, and DES 3 × 2pt data gives (Ω M , w ) = (0.321 ± 0.007, −0.941 ± 0.026). In all cases, dark energy is consistent with a cosmological constant to within ∼2 σ . Systematic errors on cosmological parameters are subdominant compared to statistical errors; these results thus pave the way for future photometrically classified SN analyses.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2023

Assessing the cloud radiative bias at Macquarie Island in the ACCESS-AM2 model

Abstract. As a long-standing problem in climate models, large positive shortwave radiation biases exist at the surface over the Southern Ocean, impacting the accurate simulation of sea surface temperature, atmospheric circulation, and precipitation. Underestimations of low-level cloud fraction and liquid water content are suggested to predominantly contribute to these radiation biases. Most model evaluations for radiation focus on summer and rely on satellite products, which have their own limitations. In this work, we use surface-based observations at Macquarie Island to provide the first long-term, seasonal evaluation of both downwelling surface shortwave and longwave radiation in the Australian Community Climate and Earth System Simulator Atmosphere-only Model version 2 (ACCESS-AM2) over the Southern Ocean. The capacity of the Clouds and the Earth’s Radiant Energy System (CERES) product to simulate radiation is also investigated. We utilize the novel lidar simulator, the Automatic Lidar and Ceilometer Framework (ALCF), and all-sky cloud camera observations of cloud fraction to investigate how radiation biases are influenced by cloud properties. Overall, we find an overestimation of +9.5±33.5 W m−2 for downwelling surface shortwave radiation fluxes and an underestimation of -2.3±13.5 W m−2 for downwelling surface longwave radiation in ACCESS-AM2 in all-sky conditions, with more pronounced shortwave biases of +25.0±48.0 W m−2 occurring in summer. CERES presents an overestimation of +8.0±18.0 W m−2 for the shortwave and an underestimation of -12.1±12.2 W m−2 for the longwave in all-sky conditions. For the cloud radiative effect (CRE) biases, there is an overestimation of +4.8±28.0 W m−2 in ACCESS-AM2 and an underestimation of -7.9±20.9 W m−2 in CERES. An overestimation of downwelling surface shortwave radiation is associated with an underestimated cloud fraction and low-level cloud occurrence. We suggest that modeled cloud phase is also having an impact on the radiation biases. Our results show that the ACCESS-AM2 model and CERES product require further development to reduce these radiation biases not just in shortwave and in all-sky conditions, but also in longwave and in clear-sky conditions.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1974

Evaluation of cermet materials suitable for lithium lubricated thrust bearings for high temperature operation

Cerment materials (HfC - 10 wt% W; HfC - 10 wt% TaC - 10 wt%W; HfC - 2 wt% CbC - 8 wt% Mo;Hfn - 10 wt% W; Hfn - 10 wt% TaN - 10 wt% W; and ZrC - 17 wt% W) were evaluated for possible use as lithium-lubricated bearings in the control system of a nuclear reactor. Tests of compatibility with lithium were made in T-111 (Ta-8W-2Hf) capsules at temperatures up to 1090 C. The tendencies of HfC-TaC-W, HfC-CbC-Mo, and HfN-W to bond to themselves and to the refractory alloys T-111 and TZM when enclosed in lithium-filled capsules under a pressure of 2000 psi at 980 and 1200 C for 1933 hours were evaluated. Thermal expansion characteristics were determined for the same three materials from room temperature to 1200 C. On the basis of these tests, HfC-10 TaC-10W and HfN-10W were selected as the best and second best candidates, respectively, of the materials tested for the bearing application.

Sinclair, J. H.↗
NASA NTRS2000

Comparison of Aerosol Single Scattering Albedos Derived By Diverse Techniques in Two North Atlantic Experiments

Aerosol single scattering albedo w (the ratio of scattering to extinction) is important in determining aerosol climatic effects, in explaining relationships between calculated and measured radiative fluxes, and in retrieving aerosol optical depths from satellite radiances. Recently, two experiments in the North Atlantic region, TARFOX and ACE-2, determined aerosol w by a variety of techniques. The techniques included fitting of calculated to measured fluxes; retrievals of w from skylight radiances; best fits of complex refractive index to profiles of backscatter, extinction, and size distribution; and in situ measurements of scattering and absorption at the surface and aloft. Both TARFOX and ACE-2 found a fairly wide range of values for w at midvisible wavelengths, with 0.85 less than wmidvis less than 0.99 for the marine aerosol impacted by continental pollution. Frequency distributions of w could usually be approximated by lognormals in wmax-w, with some occurrence of bimodality, suggesting the influence of different aerosol sources or processing. In both TARFOX and ACE-2, closure tests between measured and calculated radiative fluxes yielded best-fit values of wmidvis of 0.90+/-0.04 for the polluted boundary layer. Although these results have the virtue of describing the column aerosol unperturbed by sampling, they are subject to questions about representativeness and possible artifacts (e.g., unknown gas absorption). The other techniques gave larger values for wmidvis for the polluted boundary layer, with a typical result of wmidvis = 0.95+/-0.04, Current uncertainties in vv are large in terms of climate effects. More tests are needed of the consistency among different methods and of humidification effects on w.

Russell, P. B.↗
DOE OSTI2024

Syntheses of Tungsten Imido Cyclohexylidene Complexes Using Perfluoro‐ t ‐Butanol or Hexafluoro‐ t ‐Butanol as Acids

Abstract The fluorinated alcohols, (CF 3 ) 3 COH (R F9 OH) and (CF 3 ) 2 MeCOH (R F6 OH), react with W(NR) 2 Cy 2 (Cy=Cyclohexyl; R=2,6‐diisopropylphenyl or 1‐adamantyl) in C 6 D 6 at 55 °C to give cyclohexylidene complexes. Traditional routes to terminal alkylidene complexes (neopentylidene or neophylidene) have used either triflic acid or HCl (rarely), but relatively weak fluorinated acids are sufficient and active bisalkoxide catalysts are therefore prepared directly. An α hydrogen abstraction reaction to give a cyclohexylidene complex from a biscyclohexyl complex appears to be as facile as α hydrogen abstraction to give a neopentylidene or neophylidene ligand, but isomerization of a cyclohexene formed through β hydrogen abstraction is also a possibility. The OR F9 ligands can be replaced readily with dimethylpyrrolide (Me 2 Pyr) or other more basic alkoxides. Single crystal X‐ray studies were carried out on W(NAr) 2 Cy 2 , W(NAr)(OR F9 ) 2 (C 6 H 10 )(ArNH 2 ), W(NAr)(OR F6 ) 2 (C 6 H 10 )(ArNH 2 ), W(NAd)(OR F9 ) 2 (C 6 H 10 )(AdNH 2 ), W(NAr)(O‐ i ‐Pr F6 ) 3 Cy, and W(NAd)(η 1 ‐Me 2 Pyr) 2 (C 6 H 10 ) (C 6 H 10 =cyclohexylidene).

Maji, Milan↗
DOE OSTI2026

Mechanical characterization of fine-grain dispersion-strengthened tungsten as a plasma facing material

Field-Assisted Sintering Technology (FAST) was used to produce fine-grained, dispersion-strengthened tungsten (W) materials. Investigated materials 4138, 4353, and 4355 composed of 3 wt% ZrC sintered at 1800 °C, 5 wt% ZrC sintered at 1800 °C, and 3 wt% ZrC sintered at 2000 °C, respectively. They were compared against ITER-grade W. A series of mechanical and thermal property testing and microstructure studies were conducted to study them as a potential plasma facing material (PFM) for fusion reactors. Hardness testing showed that manufacturing conditions substantially altered hardness. Material 4355 had an average HV10 value of 497.2 ± 16.8, slightly higher than ITER-grade at 378.5 ± 40.3. However, material 4353 was substantially higher with an HV10 value of 738.9 ± 31.7 over the investigated temperature range. Electron Backscatter Diffraction (EBSD) analysis showed that FAST produced substantially smaller grains than the hot-rolled ITER-grade W material, offering notable control over grain size. Materials 4353 and 4355 had grain sizes of 0.44 ± 0.20 µm and 3.67 ± 0.89 µm, respectively, whereas ITER-grade 27.14 ± 19.76 µm at room temperature. The fine grain structures showed no net coarsening after 1 hr. anneals up to 1800 °C, several hundred degrees above the 1100 – 1500 °C recrystallization range reported for conventional W. Inverse application of the Zener pinning relationship to the measured grain sizes indicates that these two FAST sintering conditions produce markedly different effective dispersoid populations, with effective particle diameters of approximately 90 nm at a peak sintering temperature of 1800 °C and approximately 460 nm at 2000 °C, respectively. This result demonstrates that the FAST thermal condition itself, and not the nominal ZrC content alone, governs the pinning effectiveness of the dispersion. Thermal diffusivity measurements support this finding independently. Materials of identical composition sintered at different temperatures differ by approximately 19% in measured thermal diffusivity with statistically indistinguishable density, while materials of different composition and sintering temperature converge to within approximately 2%. At a representative divertor heat flux of 10 MW/m², the lower thermal conductivity of the fine-grained materials corresponds to approximately 28 to 33 °C per millimeter of armor thickness relative to ITER-grade W, traded against a substantially larger margin to recrystallization-driven degradation. While high temperature tensile testing revealed likely contamination that motivates refinement of the manufacturing process, FAST-produced, fine-grained, dispersion-strengthened W offers process-controlled microstructural stability well above the operating temperatures of conventional W and supports its continued development as a PFM for economically viable commercial fusion power.

Parker, Gabe [ORNL] (ORCID:0000000190394100)↗
DOE OSTI2022

Intense cyclic heating effects on thermo-fracture and thermal shock of solid tungsten and open-cell tungsten foam

Here we investigate here the effects of transient (cyclic) arc-jet plasma and laser heating on fracture behavior of W-foam and solid tungsten. The two key parameters that control the foam thermomechanical response are its density and mean cell size expressed in Pores Per Inch (PPI). Tungsten foam samples were fabricated with Chemical Vapor Deposition (CVD) with variety of PPI and relative density. These were tested under two types of qualitatively different conditions: (1) high-enthalpy arc-jet, and (2) high-power cyclic laser heating. None of the foam samples showed macroscopic through-thickness cracks. However, distributed micro-cracks were observed on ligaments and their triple junctions. Under the same loading conditions, W-foam and solid tungsten showed similar crack network pattern and characteristic length-scale. However, Crack Opening Displacement (COD) was twice as large in solid W as compared to W-foam. Foam samples that have been previously exposed to a low-pressure helium plasma showed significant changes in their surface forming nano-texture fuzz which was removed by subsequent testing in the arc-jet. Extensive fracture and re-crystallization were observed in the thin solid W disk that was fully-constrained from expansion. Thicker and fully-constrained solid W disks did not display recrystallization, grain growth, and extensive cracking. However, thicker disks that were free to expand showed some recrystallization and extensive through-thickness cracks due to less effective cooling and thus higher temperatures. Laser beam testing showed no visible damage formation at 0.19 GW/m 2 and 0.38 GW/m 2 for both low-density (23%) and high-density (43%) foams at low pulses (100-1000). Micro-cracks were observed after 10,000 pulses at 0.19 GW/m 2 in both foams, and in low-density foam after 100,000 at 0.38 GW/m 2 . The nature of thermomechanical damage in W-foam exposed to extreme power (GW/m 2 ) short-duration laser pulses was found to be qualitatively similar to that of high power (MW/m 2 ) long-duration arc-jet.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Behavior and properties of helium cavities in ductile-phase-toughened tungsten irradiated with He + ions at an elevated temperature

Ductile-phase toughened tungsten (DPT W) composites have demonstrated a great potential for plasma-facing components in fusion power systems. These materials can retain the outstanding thermomechanical properties of W while significantly enhancing the fracture toughness. The DPT W composite in this study consists of W particles (88 wt.%) embedded in a ductile NiFeW (12 wt.%) solution matrix. Irradiation of the composite was performed with 90 keV He + ions to 1.0 × 10 17 He + /cm 2 at 973 K. The He cavities formed in both W and NiFeW phases are examined using convergent-beam scanning transmission electron microscopy (CB-STEM) at an atomic-level resolution. Full-range depth profiles of the He cavity diameters and number densities are analyzed. The results show that the average cavity diameter in NiFeW is ~2.7 times that in W, while the number density is an order of magnitude lower. A quantitative analysis of the He density and pressure in the cavities is also achieved using STEM electron energy loss spectroscopy (STEM-EELS) mapping. The He atoms in the cavities in NiFeW are found to be under-pressurized, while those in similar-sized cavities in W are not detectable. Further, the He energy-loss shift exhibits a linear relationship with the He density in cavities in NiFeW, with the slope comparable to that for martensitic steel.

36 MATERIALS SCIENCE↗