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DOE OSTI2020

Materials Data on Li8Fe7P12WO48 by Materials Project

Li8WFe7P12O48 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Li sites. In the first Li site, Li is bonded in a distorted see-saw-like geometry to four O atoms. There are a spread of Li–O bond distances ranging from 1.95–1.99 Å. In the second Li site, Li is bonded in a distorted see-saw-like geometry to four O atoms. There are a spread of Li–O bond distances ranging from 1.95–2.03 Å. In the third Li site, Li is bonded to four O atoms to form distorted LiO4 trigonal pyramids that share corners with four PO4 tetrahedra and edges with two FeO6 octahedra. There are a spread of Li–O bond distances ranging from 1.93–2.02 Å. In the fourth Li site, Li is bonded in a distorted see-saw-like geometry to four O atoms. There are a spread of Li–O bond distances ranging from 1.93–1.98 Å. In the fifth Li site, Li is bonded in a rectangular see-saw-like geometry to four O atoms. There are a spread of Li–O bond distances ranging from 1.91–1.98 Å. In the sixth Li site, Li is bonded in a rectangular see-saw-like geometry to four O atoms. There are a spread of Li–O bond distances ranging from 1.90–2.15 Å. In the seventh Li site, Li is bonded in a distorted see-saw-like geometry to four O atoms. There are a spread of Li–O bond distances ranging from 1.96–2.03 Å. In the eighth Li site, Li is bonded in a distorted see-saw-like geometry to four O atoms. There are a spread of Li–O bond distances ranging from 1.92–2.17 Å. W is bonded to six O atoms to form WO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of W–O bond distances ranging from 1.90–1.98 Å. There are seven inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.94–2.11 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Fe–O bond distances ranging from 1.97–2.08 Å. In the third Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Fe–O bond distances ranging from 1.95–2.10 Å. In the fourth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.92–2.15 Å. In the fifth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.96–2.18 Å. In the sixth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.92–2.14 Å. In the seventh Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.96–2.04 Å. There are twelve 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 WO6 octahedra, corners with three FeO6 octahedra, and a cornercorner with one LiO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 21–39°. There are a spread of P–O bond distances ranging from 1.51–1.63 Å. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and a cornercorner with one LiO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 12–43°. There are a spread of P–O bond distances ranging from 1.53–1.56 Å. In the third P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 11–43°. There are a spread of P–O bond distances ranging from 1.53–1.56 Å. In the fourth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one WO6 octahedra and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 14–41°. There are a spread of P–O bond distances ranging from 1.51–1.64 Å. In the fifth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra and a cornercorner with one LiO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 10–42°. There is one shorter (1.54 Å) and three longer (1.55 Å) P–O bond length. In the sixth P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 27–36°. There is two shorter (1.53 Å) and two longer (1.56 Å) P–O bond length. In the seventh P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 26–37°. There are a spread of P–O bond distances ranging from 1.53–1.56 Å. In the eighth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one WO6 octahedra, corners with three FeO6 octahedra, and a cornercorner with one LiO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 8–44°. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. In the ninth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one WO6 octahedra and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 7–47°. There are a spread of P–O bond distances ranging from 1.51–1.64 Å. In the tenth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one WO6 octahedra and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 13–44°. There are a spread of P–O bond distances ranging from 1.51–1.64 Å. In the eleventh P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with four FeO6 octahedra. The corner-sharing octahedra tilt angles range from 11–43°. There are a spread of P–O bond distances ranging from 1.53–1.56 Å. In the twelfth P site, P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one WO6 octahedra and corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 27–34°. There are a spread of P–O bond distances ranging from 1.51–1.65 Å. There are forty-eight inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the second O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the third O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the fourth O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the fifth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the sixth O site, O is bonded in a distorted T-shaped geometry to one Li, one Fe, and one P atom. In the seventh O site, O is bonded in a linear geometry to one Fe and one P atom. In the eighth O site, O is bonded in a linear geometry to one Fe and one P atom. In the ninth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the eleventh O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the twelfth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the thirteenth O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the fourteenth O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the fifteenth O site, O is bonded in a distorted T-shaped geometry to one Li, one Fe, and one P atom. In the sixteenth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the seventeenth O site, O is bonded in a linear geometry to one Fe and one P atom. In the eighteenth O site, O is bonded in a linear geometry to one Fe and one P atom. In the nineteenth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the twentieth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the twenty-first O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the twenty-second O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the twenty-third O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the twenty-fourth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the twenty-fifth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the twenty-sixth O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the twenty-seventh O site, O is bonded in a distorted trigonal planar geometry to one Li, one W, and one P atom. In the twenty-eighth O site, O is bonded in a distorted T-shaped geometry to one Li, one Fe, and one P atom. In the twenty-ninth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the thirtieth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the thirty-first O site, O is bonded in a linear geometry to one Fe and one P atom. In the thirty-second O site, O is bonded in a linear geometry to one W and one P atom. In the thirty-third O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the thirty-fourth O site, O is bonded in a distorted trigonal non-coplanar geometry to one Li, one W, and one P atom. In the thirty-fifth O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the thirty-sixth O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the thirty-seventh O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the thirty-eighth O site, O is bonded in a distorted trigonal planar geometry to one Li, one W, and one P atom. In the thirty-ninth O site, O is bonded in a distorted trigonal non-coplanar geometry to one Li, one Fe, and one P atom. In the fortieth O site, O is bonded in a distorted trigonal planar geometry to one Li, one Fe, and one P atom. In the forty-first O site, O is bonded in a linear geometry to one Fe and one P atom. In the forty-second O site, O is bonded in a linear geometry to one Fe and one P atom. In the forty-third O site, O is bonded in a distorted T-shaped geometry to one Li, one W, and one P atom. In the forty-fourth O site, O is bonded in a distorted T-shaped geometry to one Li, one Fe, and one P atom. In the forty-fifth O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the forty-sixth O site, O is bonded in a 3-coordinate geometry to one Li, one Fe, and one P atom. In the forty-seventh O site, O is bonded in a bent 150 degrees geometry to one Fe and one P atom. In the forty-eighth O site, O is bonded in a bent 150 degrees geometry to one W and one P atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Si2W3 by Materials Project

W3Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are two inequivalent W+2.67+ sites. In the first W+2.67+ site, W+2.67+ is bonded in a square co-planar geometry to four equivalent Si4- atoms. All W–Si bond lengths are 2.58 Å. In the second W+2.67+ site, W+2.67+ is bonded to six equivalent Si4- atoms to form a mixture of distorted face, edge, and corner-sharing WSi6 pentagonal pyramids. There are two shorter (2.55 Å) and four longer (2.57 Å) W–Si bond lengths. Si4- is bonded in a 9-coordinate geometry to eight W+2.67+ and one Si4- atom. The Si–Si bond length is 2.51 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na2TeW2O9 by Materials Project

Na2TeW2O9 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 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.49–2.90 Å. In the second 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 2.31–2.89 Å. In the third 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 2.33–2.72 Å. In the fourth Na1+ site, Na1+ is bonded to seven O2- atoms to form NaO7 pentagonal bipyramids that share corners with four WO6 octahedra, an edgeedge with one NaO7 hexagonal pyramid, and edges with two WO6 octahedra. The corner-sharing octahedra tilt angles range from 35–61°. There are a spread of Na–O bond distances ranging from 2.30–2.63 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 2.34–2.96 Å. In the sixth Na1+ site, Na1+ is bonded to seven O2- atoms to form distorted NaO7 hexagonal pyramids that share a cornercorner with one WO6 octahedra, edges with three WO6 octahedra, and an edgeedge with one NaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 60°. There are a spread of Na–O bond distances ranging from 2.44–2.78 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 2.40–2.96 Å. In the eighth 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 2.38–2.91 Å. There are eight inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share corners with three WO6 octahedra, a cornercorner with one NaO7 pentagonal bipyramid, an edgeedge with one NaO7 hexagonal pyramid, and an edgeedge with one NaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 18–42°. There are a spread of W–O bond distances ranging from 1.80–2.19 Å. In the second 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, and an edgeedge with one NaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 18–42°. There are a spread of W–O bond distances ranging from 1.81–2.13 Å. In the third 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 33–44°. There are a spread of W–O bond distances ranging from 1.81–2.21 Å. In the fourth W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share corners with two WO6 octahedra, a cornercorner with one NaO7 pentagonal bipyramid, and edges with two equivalent NaO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 37–38°. There are a spread of W–O bond distances ranging from 1.79–2.22 Å. In the fifth W6+ site, W6+ is bonded to six O2- atoms to form distorted corner-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 30–44°. There are a spread of W–O bond distances ranging from 1.77–2.26 Å. In the sixth W6+ site, W6+ is bonded to six O2- atoms to form corner-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 18–43°. There are a spread of W–O bond distances ranging from 1.78–2.16 Å. In the seventh W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share a cornercorner with one NaO7 hexagonal pyramid and corners with three WO6 octahedra. The corner-sharing octahedra tilt angles range from 18–43°. There are a spread of W–O bond distances ranging from 1.81–2.22 Å. In the eighth W6+ site, W6+ is bonded to six O2- atoms to form distorted corner-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 21–41°. There are a spread of W–O bond distances ranging from 1.80–2.20 Å. There are four inequivalent Te4+ sites. In the first Te4+ site, Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There is two shorter (1.90 Å) and one longer (1.91 Å) Te–O bond length. In the second Te4+ site, Te4+ is bonded in a 6-coordinate geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.91–2.62 Å. In the third Te4+ site, Te4+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–2.70 Å. In the fourth Te4+ site, Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There is two shorter (1.91 Å) and one longer (1.92 Å) Te–O bond length. There are thirty-six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one W6+, and one Te4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+ and one W6+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two W6+ atoms. 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 bent 150 degrees geometry to two W6+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and one W6+ atom. In the eighth O2- site, O2- is bonded to three Na1+ and one W6+ atom to form a mixture of distorted edge and corner-sharing ONa3W tetrahedra. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one W6+, and one Te4+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, one W6+, and one Te4+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te4+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te4+ atom. In the thirteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and one W6+ atom. In the fourteenth O2- site, O2- is bonded to three Na1+ and one W6+ atom to form corner-sharing ONa3W tetrahedra. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and two W6+ atoms. In the sixteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two W6+ atoms. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to two W6+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one W6+, and one Te4+ atom. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te4+ atom. In the twentieth O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+ and one W6+ atom. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te4+ atom. In the twenty-second O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+ and two W6+ atoms. In the twenty-third O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and one W6+ atom. In the twenty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one W6+ atom. In the twenty-fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two W6+, and one Te4+ atom. In the twenty-sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te4+ atom. In the twenty-seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te4+ atom. In the twenty-eighth O2- site, O2- is bonded to three Na1+ and one W6+ atom to form a mixture of distorted edge and corner-sharing ONa3W trigonal pyramids. In the twenty-ninth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one W6+ atom. In the thirtieth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te4+ atom. In the thirty-first O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+ and two W6+ atoms. In the thirty-second O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one W6+, and one Te4+ atom. In the thirty-third O2- site, O2- is bonded in a 3-coordinate geometry to two Na1+ and one W6+ atom. In the thirty-fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two W6+ atoms. In the thirty-fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and two W6+ atoms. In the thirty-sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and two W6+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba2Li3Ho3(WO4)8 by Materials Project

Li3Ba2Ho3(WO4)8 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 1.97–2.54 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 1.98–2.50 Å. In the third Li1+ site, Li1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Li–O bond distances ranging from 2.29–2.64 Å. There are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.65–3.33 Å. In the second Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.63–3.26 Å. There are three inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ho–O bond distances ranging from 2.25–2.51 Å. In the second Ho3+ site, Ho3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ho–O bond distances ranging from 2.29–2.45 Å. In the third Ho3+ site, Ho3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ho–O bond distances ranging from 2.28–2.50 Å. There are eight inequivalent W6+ sites. In the first W6+ site, W6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of W–O bond distances ranging from 1.82–1.84 Å. In the second W6+ site, W6+ is bonded to five O2- atoms to form distorted corner-sharing WO5 tetrahedra. There are a spread of W–O bond distances ranging from 1.79–2.40 Å. In the third W6+ site, W6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of W–O bond distances ranging from 1.82–1.85 Å. In the fourth W6+ site, W6+ is bonded in a distorted tetrahedral geometry to four O2- atoms. There are a spread of W–O bond distances ranging from 1.80–1.88 Å. In the fifth W6+ site, W6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of W–O bond distances ranging from 1.81–1.87 Å. In the sixth W6+ site, W6+ is bonded to four O2- atoms to form distorted corner-sharing WO4 tetrahedra. There are a spread of W–O bond distances ranging from 1.80–1.89 Å. In the seventh W6+ site, W6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of W–O bond distances ranging from 1.81–1.85 Å. In the eighth W6+ site, W6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of W–O bond distances ranging from 1.80–1.88 Å. There are thirty-two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Ho3+, and one W6+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ho3+ and one W6+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ho3+, and one W6+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ho3+ and one W6+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+, one Ba2+, and one W6+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+, one Ba2+, and one W6+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+, one Ba2+, and one W6+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom. In the fourteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+, one Ho3+, and one W6+ atom. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+, one Ho3+, and one W6+ atom. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Ho3+, and one W6+ atom. In the seventeenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Ho3+, and one W6+ atom. In the eighteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ho3+ and one W6+ atom. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ho3+, and one W6+ atom. In the twentieth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ho3+ and one W6+ atom. In the twenty-first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Ho3+, and one W6+ atom. In the twenty-second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ho3+ and one W6+ atom. In the twenty-third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ho3+, and one W6+ atom. In the twenty-fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ho3+ and one W6+ atom. In the twenty-fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom. In the twenty-sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+, one Ho3+, and one W6+ atom. In the twenty-seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Ho3+, and one W6+ atom. In the twenty-eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+, one Ho3+, and one W6+ atom. In the twenty-ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom. In the thirtieth O2- site, O2- is bonded in a 1-coordinate geometry to one Li1+, one Ba2+, and two W6+ atoms. In the thirty-first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom. In the thirty-second O2- site, O2- is bonded in a 1-coordinate geometry to one Li1+, one Ba2+, and one W6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfAlW4 by Materials Project

HfW4Al is Hexagonal Laves-derived structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Hf is bonded in a 12-coordinate geometry to twelve equivalent W and four equivalent Al atoms. All Hf–W bond lengths are 3.13 Å. All Hf–Al bond lengths are 3.26 Å. W is bonded to three equivalent Hf, six equivalent W, and three equivalent Al atoms to form a mixture of corner, edge, and face-sharing WHf3Al3W6 cuboctahedra. There are three shorter (2.66 Å) and three longer (2.68 Å) W–W bond lengths. All W–Al bond lengths are 3.12 Å. Al is bonded in a 12-coordinate geometry to four equivalent Hf and twelve equivalent W atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfZrW4 by Materials Project

HfZrW4 is Cubic Laves-derived structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Hf is bonded in a 12-coordinate geometry to four equivalent Zr and twelve equivalent W atoms. All Hf–Zr bond lengths are 3.31 Å. All Hf–W bond lengths are 3.17 Å. Zr is bonded in a 12-coordinate geometry to four equivalent Hf and twelve equivalent W atoms. All Zr–W bond lengths are 3.17 Å. W is bonded to three equivalent Hf, three equivalent Zr, and six equivalent W atoms to form a mixture of corner, edge, and face-sharing WHf3Zr3W6 cuboctahedra. All W–W bond lengths are 2.71 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li3(WO3)8 by Materials Project

Li3(WO3)8 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a distorted square co-planar geometry to four equivalent O2- atoms. All Li–O bond lengths are 2.15 Å. In the second Li1+ site, Li1+ is bonded in a distorted square co-planar geometry to four equivalent O2- atoms. All Li–O bond lengths are 2.15 Å. In the third Li1+ site, Li1+ is bonded in a distorted square co-planar geometry to four equivalent O2- atoms. All Li–O bond lengths are 2.16 Å. W+5.62+ is bonded to six O2- atoms to form corner-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 26–31°. There are a spread of W–O bond distances ranging from 1.93–1.97 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent W+5.62+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent W+5.62+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+ and two equivalent W+5.62+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+ and two equivalent W+5.62+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent W+5.62+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+ and two equivalent W+5.62+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZrSiW4 by Materials Project

ZrW4Si is Hexagonal Laves-derived structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Zr is bonded in a 12-coordinate geometry to twelve equivalent W and four equivalent Si atoms. All Zr–W bond lengths are 3.13 Å. All Zr–Si bond lengths are 3.27 Å. W is bonded to three equivalent Zr, six equivalent W, and three equivalent Si atoms to form a mixture of face, edge, and corner-sharing WZr3Si3W6 cuboctahedra. There are three shorter (2.65 Å) and three longer (2.68 Å) W–W bond lengths. All W–Si bond lengths are 3.13 Å. Si is bonded in a 12-coordinate geometry to four equivalent Zr and twelve equivalent W atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Progress and Challenges of Additive Manufacturing of Tungsten and Alloys as Plasma-Facing Materials

Tungsten (W) and W alloys are considered as primary candidates for plasma-facing components (PFCs) that must perform in severe environments in terms of temperature, neutron fluxes, plasma effects, and irradiation bombardment. These materials are notoriously difficult to produce using additive manufacturing (AM) methods due to issues inherent to these techniques. The progress on applying AM techniques to W-based PFC applications is reviewed and the technical issues in selected manufacturing methods are discussed in this review. Specifically, we focus on the recent development and applications of laser powder bed fusion (LPBF), electron beam melting (EBM), and direct energy deposition (DED) in W materials due to their abilities to preserve the properties of W as potential PFCs. Additionally, the existing literature on irradiation effects on W and W alloys is surveyed, with possible solutions to those issues therein addressed. Finally, the gaps in possible future research on additively manufactured W are identified and outlined.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Search for vector-boson resonances decaying into a top quark and a bottom quark using $p p$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

A search for a new massive charged gauge boson, $W'$, is performed with the ATLAS detector at the LHC. The dataset used in this analysis was collected from proton–proton collisions at a centre-of-mass energy of $\sqrt{s}$ = 13 TeV, and corresponds to an integrated luminosity of 139 fb -1 . The reconstructed tb invariant mass is used to search for a $W'$ boson decaying into a top quark and a bottom quark. The result is interpreted in terms of a $W'$ boson with purely right-handed or left-handed chirality in a mass range of 0.5–6 TeV. Different values for the coupling of the $W'$ boson to the top and bottom quarks are considered, taking into account interference with single-top-quark production in the $s$-channel. No significant deviation from the background prediction is observed. The results are expressed as upper limits on the $W'$ → $tb$ production cross-section times branching ratio as a function of the $W'$-boson mass and in the plane of the coupling vs the $W'$-boson mass.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2022

Origins of wear-induced tungsten corrosion defects in semiconductor manufacturing during tungsten chemical mechanical polishing

During chemical mechanical polishing (CMP) process optimization, a unique corrosion defect was identified in the tungsten (W) contact plugs, which were investigated to develop practical solutions to improve CMP mass productivity. The corrosion defect occurred in the absence of external incident energy and was observed to occur only at the W plugs connected to the P + /n-well close to the wafer edge. To examine the root cause of the corrosion, a series of experiments was carried out at each W CMP step, using in-line defect inspection. Additional experiments were conducted using on-line inductively coupled plasma mass spectrometry (ICP-MS) to understand pH- and potential-dependent electrochemical dissolution behaviors of W. Experimentally, W corrosion was confirmed to be exacerbated if the surface oxide of the W plugs is removed by the deionized water (DIW) rinsing step under wafer pressurization, then exposed to DIW and alkaline cleaning solution. Although the DIW rinsing step is commonly performed to clean polishing pads right after the main polishing, a small amount of applied pressure (0.5 psi) without slurry supply can lead to corrosion defects. Finally, this wear-induced corrosion of the W plugs can be prevented by removing the applied pressure during the post DIW rinsing step of W CMP.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Effect of rhenium addition on deuterium retention in neutron-irradiated tungsten

In this work, the effects of rhenium (Re) addition on deuterium (D) retention in neutron-irradiated tungsten (W) were investigated. Pure W and W-5Re (5 at.%) alloy samples were irradiated with neutrons at High Flux Isotope Reactor using MFE-RB-19 J capsule. The sample temperature and the damage level were 864 K and 0.35 dpa for pure W and 792 K and 0.26 dpa for W-5Re alloy. A portion of the samples was exposed to D plasma at Tritium Plasma Experiment at Idaho National Laboratory at 823 K to a fluence of 5 × 1025 m -2 . Vacancy-type defects in neutron-irradiated samples were examined using positron annihilation spectroscopy (PAS); D retention after plasma exposure was evaluated by thermal desorption spectrometry (TDS). TDS measurements revealed that D retention in the neutron-irradiated W-5Re alloy was similar to that in the unirradiated W sample, whereas a significant increase in D retention was observed in neutron-irradiated W. Thus, Re addition significantly suppressed the increase in D retention after neutron irradiation. This effect was attributed to the suppression of vacancy-type defect formation, as confirmed by PAS.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

The diurnally-averaged aerosol direct radiative effect and the use of the daytime-mean and insolation-weighted-mean solar zenith angles

Here, this study examines the application of the daytime-mean and insolation-weighted-mean solar zenith angles to calculate the diurnally-averaged aerosol direct radiative effect (DRE), DRE DA , for observed clear-sky conditions at the Atmospheric Radiation Measurement Program (ARM) Southern Great Plains (SGP) and Tropical Western Pacific (TWP) sites. As compared with the reference calculation, the DRE DA are too strong (i.e., more negative) using daytime-mean solar zenith angles (DTMSZA) and are too weak (i.e., less negative) using insolation-weighted-mean solar zenith angles (IWMSZA). The biases in the DRE DA for DTMSZA (IWMSZA) are about -0.8 (0.7) W m -2 at the TOA and about -1.5 (0.9) W m -2 at the surface. Noting the mean TOA DRE DA of -2.85 W m -2 and the surface DRE DA of -7.09 W m -2 at SGP, the relative biases for DTMSZA (IWMSZA) are 26% (-24%) for the TOA DRE DA , and 17% (-11%) for the surface DRE DA . At TWP, the mean TOA DRE DA is -2.81 W m -2 and the surface DRE DA is -11.84 W m -2 which corresponds to relative biases for DTMSZA (IWMSZA) of 29% (-27%) for the TOA DRE DA and 15% (-9%) for the surface DRE DA . By introducing an adjusted insolation-weighted-mean solar zenith angle, the mean biases in the DRE DA at the TOA becomes -0.09 W m -2 and the biases in the DRE DA at the surface are about -0.41 W m -2 . Also presented are the effects of using the mean solar zenith angles on the shortwave (SW) upward fluxes at the TOA and SW downward fluxes at the surface in both clear-sky and pristine-clear-sky (i.e., gases only) conditions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Improving Aerosol Radiative Forcing and Climate in E3SM: Impacts of New Cloud Microphysics and Improved Wet Removal Treatments

Abstract Numerous Earth system models exhibit excessive aerosol effective forcing at the top of the atmosphere (TOA), including the Department of Energy's Energy Exascale Earth System Model (E3SM). Here, in the context of the E3SM version 3 effort, the predicted particle property (P3) stratiform cloud microphysics scheme and an enhanced deep convection parameterization suite (ZM_plus) are implemented into E3SM. The ZM_plus includes a convective cloud microphysics scheme, a multi‐scale coherent structure parameterization for mesoscale convective systems, and a revised cloud base mass flux formulation considering impacts of the large‐scale environment. The P3 scheme improved cloud and radiation particularly over the Northern Hemisphere and the frequency of heavy precipitation over the tropics, and the ZM_plus improved clouds in the tropics. P3 decreases aerosol effective forcing by 0.15 W m −2 , while the ZM_plus increases it by 0.27 W m −2 , resulting from excessive direct (0.31 W m −2 ) and indirect forcing (−1.79 W m −2 ). The excessive aerosol forcings are due to aerosol overestimation associated with insufficient aerosol wet removal. By improving the physical treatments in the aerosol wet removal, we effectively mitigate anthropogenic aerosol overestimation and thus attenuate direct (0.09 W m −2 ) and indirect aerosol forcing (−1.52 W m −2 ). Adjustment to primary organic matter hygroscopicity reduces direct and indirect forcing to more reasonable values: −0.13 W m −2 and −1.31 W m −2 , respectively. On climatology, improved aerosol treatments mitigate overestimation of aerosol optical depth.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Machine learned interatomic potential for dispersion strengthened plasma facing components

Tungsten (W) is a material of choice for the divertor material due to its high melting temperature, thermal conductivity, and sputtering threshold. However, W has a very high brittle-to-ductile transition temperature, and at fusion reactor temperatures (≥1000 K), it may undergo recrystallization and grain growth. Dispersion-strengthening W with zirconium carbide (ZrC) can improve ductility and limit grain growth, but much of the effects of the dispersoids on microstructural evolution and thermomechanical properties at high temperatures are still unknown. We present a machine learned Spectral Neighbor Analysis Potential for W–ZrC that can now be used to study these materials. In order to construct a potential suitable for large-scale atomistic simulations at fusion reactor temperatures, it is necessary to train on ab initio data generated for a diverse set of structures, chemical environments, and temperatures. Further accuracy and stability tests of the potential were achieved using objective functions for both material properties and high temperature stability. Additionally, validation of lattice parameters, surface energies, bulk moduli, and thermal expansion is confirmed on the optimized potential. Tensile tests of W/ZrC bicrystals show that although the W(110)–ZrC(111) C-terminated bicrystal has the highest ultimate tensile strength (UTS) at room temperature, observed strength decreases with increasing temperature. At 2500 K, the terminating C layer diffuses into the W, resulting in a weaker W–Zr interface. Meanwhile, the W(110)–ZrC(111) Zr-terminated bicrystal has the highest UTS at 2500 K.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Fast response, optical radiance measurements of low intensity impurity emission in WEST plasmas with staggered wavelength filters

Fast response acquisition of atomic line emission through the use of a filterscope has been implemented on the WEST tokamak at multiple poloidal locations. Filterscopes consist of a fiber-optic-based transmission from the tokamak to specifically engineered optical bandpasses and photomultiplier tubes (PMT) that collect the emission intensity to measure a radiance, L [W/cm2/str], over the specified bandpass. This diagnostic records plasma-wall interaction (PWI) properties (e.g. impurity emission and recycling of main fuel ions) up to a max acquisition rate of 100 kHz. These PMT radiometric measurements are calibrated into a line-normalized radiance, LN [photons/sec/cm2/str], similar to traditional spectrometers, which can later be converted to a particle flux. Low intensity emission peaks are difficult to quantify due to often comparable continuum levels, thus a secondary filter shifted to a judiciously-selected, line-free region (~1 nm away) allows for background subtraction. The system currently installed on WEST targets tungsten (W) gross sputtering specifically by monitoring, with a filter pair, the spectral region near the neutral W line emission (W I 400.9 nm). The line and background filters of the pair are centered at 400.6 nm and 403.1 nm, respectively. Through a set beam splitters on each sight line, the filter pair are measuring from the same location. The two L signals near W I are then subtracted from each other yielding only the W I LN. W I LN data from a recent WEST experimental campaign is presented and compared with plasma parameters and traditional spectrometer measurements of W I line emission to demonstrate the capabilities of this staggered-filter filterscope method. Specifically, the choice of WEST-specific bandpass curves for the W I LN will be illustrated based on this latter comparison.

Neff, Anton↗
DOE OSTI2025

Rapid Bayesian High Entropy Alloy Designs Fabricated via Wire Arc Additive Manufacturing

Purpose: This project seeks to demonstrate a new high-throughput (rapid) alloy design technique applied to creating new high entropy alloys (HEAs) for extreme environments. High entropy alloys shift the design paradigm from being focused on a single principal element (e.g. nickel-based alloys) to target alloys that include high atomic fractions (X >10%) of multiple elements. These HEA materials can exhibit sluggish diffusion and enhanced corrosion resistance, ideal for potential applications in advanced ultra supercritical (A-USC) steam cycles for power generation. Scope: The addition of multiple elements in high atomic fractions creates an enormous design space that cannot easily be investigated by traditional material design strategies such as designed of experiments (DOE). This project utilizes a Bayesian machine learning algorithm that has been modified to work with calculation of phase diagrams (CALPHAD) software. This Bayesian algorithm reduces manual inputs and increase the likelihood of achieving an optimal solution. Compositional inputs to this algorithm will be assessed using existing material property models for high temperature strength and corrosion resistance. The target for alloy performance will be a 15% (~100 ⁰C) increase in allowable service temperature beyond heat-resistant stainless steels while maintaining or improving alloy cost and corrosion resistance. Haynes 230 was selected as a baseline, which is 57 wt% Ni with 22 wt% Cr 14 wt% W, and 2 wt% Mo as solid solution strengtheners. In addition to rapid design via Bayesian machine learning, the alloys were rapidly fabricated using a multi-wire arc additive manufacturing (mWAAM) technique which allows for precise control of alloy composition and assessing of alloy design “windows” to study composition effects. Build speeds for wire-arc additive processes are among the highest for additive technologies enabling rapid and reliable sample fabrication when compared to conventional methods such as arc button melting. The mWAAM samples will be rapidly characterized via instrumented indentation for room temperature modulus and strength and for elevated temperature strength via hot hardness tests. After being screened with hardness testing, potential alloys will be further evaluated with conventional microscopy techniques including scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to assess agreement with modeling results. The most promising compositions will also be evaluated by printing full sized tensile specimens for mechanical behavior tests at elevated temperatures. Results: Bayesian machine learning of a single performance function was initially used to optimize five performance metrics: 1) single phase stability, 2) yield strength, 3) creep resistance (low diffusion coefficient), 4) freezing range (weldability), and 5) material cost. The single performance function was suboptimal as assumptions had to be made about the results while formulating the optimization. A goal-oriented Bayesian optimization strategy (Hanaoka, 2021) was implemented with CALPHAD for use with the five metrics above. This multi-objective Bayesian optimization (MOBO) enabled the design of NiCrCoFe alloys with V and W additions. A base composition of NiCoCr was selected as Ni provides a stable FCC matrix, Cr aids corrosion/oxidation resistance, and Co is a solid-solutions strengthener that also improves creep by increasing the activation energy. Fe helps reduce diffusion coefficients and cost. Finally, V and W were selected for their reasonable solubility and high atomic misfit to aid in solid solution strengthening. Cracking of the mWAAM specimens was an early issue, and the Easton solidification cracking model (Easton et al., 2014a) was selected for addition to the MOBO function. High performing alloys fabricated by mWAAM included Ni 28 Cr 25 Co 26 Fe 15 V 8 and Ni 62 Cr 18 Co 1 Fe 3 W 15 . It was observed that even after adapting the mWAAM process for W, the W did not fully dissolve. To fully evaluate the Ni 62 Cr 18 Co 1 Fe 3 W 15 composition, a cored wire (80-20 NiCr sheath/powder core) was manufactured and printed via WAAM, and HIP’ing was utilized to homogenize and densify the printed alloy. The V and W alloys produced met metrics 1 (solid solution), 4 (solidification cracking), and 5 (cost). However, an unmodeled mechanism of thermal stress cracking was identified in the WAAM produced materials, perhaps exacerbated by the lack of grain boundary strengthening elements (B, C). Conclusions & Recommendations: A high-throughput (rapid) alloy design technique was applied to designing and manufacturing new high entropy alloys (HEAs) for extreme environments utilizing MOBO and mWAAM. The developed process was rapid and effective in addressing the mechanisms included in the model. The lack of grain boundary strengthening element additions (e.g., B, C) was a simplification that likely produced thermal stress cracking that turned into a large part of the investigation. Additions on the order of 0.005 wt% B and 0.05 wt% C likely would have minimized thermal stress grain boundary cracking. Overall, the high throughput design strategy is promising for rapid design of metrics-driven alloys for advanced ultra supercritical (A-USC) steam cycles for power generation. The MOBO and mWAAM process could be commercialized to accelerate metrics-driven alloy design. In addition, the cored-wire process utilized for scale-up is a promising high-volume process for WAAM alloy development and scale-up.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Effective radiative forcing and adjustments in CMIP6 models

Abstract. The effective radiative forcing, which includes the instantaneous forcing plus adjustments from the atmosphere and surface, has emerged as the key metric of evaluating human and natural influence on the climate. We evaluate effective radiative forcing and adjustments in 17 contemporary climate models that are participating in the Coupled Model Intercomparison Project (CMIP6) and have contributed to the Radiative Forcing Model Intercomparison Project (RFMIP). Present-day (2014) global-mean anthropogenic forcing relative to pre-industrial (1850) levels from climate models stands at 2.00 (±0.23) W m−2, comprised of 1.81 (±0.09) W m−2 from CO2, 1.08 (± 0.21) W m−2 from other well-mixed greenhouse gases, −1.01 (± 0.23) W m−2 from aerosols and −0.09 (±0.13) W m−2 from land use change. Quoted uncertainties are 1 standard deviation across model best estimates, and 90 % confidence in the reported forcings, due to internal variability, is typically within 0.1 W m−2. The majority of the remaining 0.21 W m−2 is likely to be from ozone. In most cases, the largest contributors to the spread in effective radiative forcing (ERF) is from the instantaneous radiative forcing (IRF) and from cloud responses, particularly aerosol–cloud interactions to aerosol forcing. As determined in previous studies, cancellation of tropospheric and surface adjustments means that the stratospherically adjusted radiative forcing is approximately equal to ERF for greenhouse gas forcing but not for aerosols, and consequentially, not for the anthropogenic total. The spread of aerosol forcing ranges from −0.63 to −1.37 W m−2, exhibiting a less negative mean and narrower range compared to 10 CMIP5 models. The spread in 4×CO2 forcing has also narrowed in CMIP6 compared to 13 CMIP5 models. Aerosol forcing is uncorrelated with climate sensitivity. Therefore, there is no evidence to suggest that the increasing spread in climate sensitivity in CMIP6 models, particularly related to high-sensitivity models, is a consequence of a stronger negative present-day aerosol forcing and little evidence that modelling groups are systematically tuning climate sensitivity or aerosol forcing to recreate observed historical warming.

54 ENVIRONMENTAL SCIENCES↗