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Materials Data on Re3Pb3O10 by Materials Project

Re3Pb3O10 crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. there are two inequivalent Re+4.67+ sites. In the first Re+4.67+ site, Re+4.67+ is bonded to six O2- atoms to form ReO6 octahedra that share corners with six ReO6 octahedra, edges with two equivalent PbO8 hexagonal bipyramids, and edges with four equivalent PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 40–43°. There are a spread of Re–O bond distances ranging from 1.98–2.01 Å. In the second Re+4.67+ site, Re+4.67+ is bonded to six O2- atoms to form ReO6 octahedra that share corners with six ReO6 octahedra, edges with two equivalent PbO8 hexagonal bipyramids, and edges with four equivalent PbO7 hexagonal pyramids. The corner-sharing octahedra tilt angles range from 39–41°. There is two shorter (1.98 Å) and four longer (1.99 Å) Re–O bond length. There are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded to seven O2- atoms to form distorted PbO7 hexagonal pyramids that share corners with three equivalent PbO7 hexagonal pyramids, edges with two equivalent PbO8 hexagonal bipyramids, an edgeedge with one PbO7 hexagonal pyramid, and edges with six ReO6 octahedra. There are a spread of Pb–O bond distances ranging from 2.21–2.77 Å. In the second Pb2+ site, Pb2+ is bonded to eight O2- atoms to form PbO8 hexagonal bipyramids that share edges with two equivalent PbO8 hexagonal bipyramids, edges with four equivalent PbO7 hexagonal pyramids, and edges with six ReO6 octahedra. There are two shorter (2.44 Å) and six longer (2.70 Å) Pb–O bond lengths. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two Re+4.67+ and two Pb2+ atoms. In the second O2- site, O2- is bonded to four Pb2+ atoms to form corner-sharing OPb4 tetrahedra. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Re+4.67+ and two equivalent Pb2+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Re+4.67+ and two equivalent Pb2+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Re+4.67+ and two equivalent Pb2+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Re+4.67+ and two equivalent Pb2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3Os by Materials Project

Re3Os is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Re sites. In the first Re site, Re is bonded to eight Re and four equivalent Os atoms to form distorted ReRe8Os4 cuboctahedra that share corners with four equivalent OsRe12 cuboctahedra, corners with fourteen equivalent ReRe8Os4 cuboctahedra, edges with six equivalent OsRe12 cuboctahedra, edges with twelve ReRe8Os4 cuboctahedra, faces with four equivalent OsRe12 cuboctahedra, and faces with sixteen ReRe8Os4 cuboctahedra. There are a spread of Re–Re bond distances ranging from 2.73–2.80 Å. There are two shorter (2.75 Å) and two longer (2.78 Å) Re–Os bond lengths. In the second Re site, Re is bonded to eight equivalent Re and four equivalent Os atoms to form distorted ReRe8Os4 cuboctahedra that share corners with four equivalent OsRe12 cuboctahedra, corners with fourteen ReRe8Os4 cuboctahedra, edges with six equivalent OsRe12 cuboctahedra, edges with twelve equivalent ReRe8Os4 cuboctahedra, faces with four equivalent OsRe12 cuboctahedra, and faces with sixteen ReRe8Os4 cuboctahedra. There are two shorter (2.75 Å) and two longer (2.78 Å) Re–Os bond lengths. Os is bonded to twelve Re atoms to form OsRe12 cuboctahedra that share corners with six equivalent OsRe12 cuboctahedra, corners with twelve ReRe8Os4 cuboctahedra, edges with eighteen ReRe8Os4 cuboctahedra, faces with eight equivalent OsRe12 cuboctahedra, and faces with twelve ReRe8Os4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3Pb by Materials Project

Re3Pb is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. there are two inequivalent Re sites. In the first Re site, Re is bonded to four equivalent Re and four equivalent Pb atoms to form a mixture of distorted edge, face, and corner-sharing ReRe4Pb4 tetrahedra. All Re–Re bond lengths are 2.80 Å. All Re–Pb bond lengths are 2.80 Å. In the second Re site, Re is bonded in a 8-coordinate geometry to eight equivalent Re and six equivalent Pb atoms. All Re–Pb bond lengths are 3.24 Å. Pb is bonded in a distorted body-centered cubic geometry to fourteen Re atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3Sb by Materials Project

Re3Sb is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. there are two inequivalent Re sites. In the first Re site, Re is bonded in a distorted body-centered cubic geometry to four equivalent Re and four equivalent Sb atoms. All Re–Re bond lengths are 2.77 Å. All Re–Sb bond lengths are 2.77 Å. In the second Re site, Re is bonded in a 8-coordinate geometry to eight equivalent Re and six equivalent Sb atoms. All Re–Sb bond lengths are 3.20 Å. Sb is bonded in a distorted body-centered cubic geometry to fourteen Re atoms.

36 MATERIALS SCIENCE↗
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Materials Data on Re3Ir by Materials Project

Re3Ir is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Re sites. In the first Re site, Re is bonded to eight Re and four equivalent Ir atoms to form ReRe8Ir4 cuboctahedra that share corners with twelve equivalent ReRe8Ir4 cuboctahedra, edges with eight equivalent IrRe12 cuboctahedra, edges with sixteen ReRe8Ir4 cuboctahedra, faces with four equivalent IrRe12 cuboctahedra, and faces with fourteen ReRe8Ir4 cuboctahedra. There are four shorter (2.76 Å) and four longer (2.77 Å) Re–Re bond lengths. All Re–Ir bond lengths are 2.77 Å. In the second Re site, Re is bonded to eight equivalent Re and four equivalent Ir atoms to form ReRe8Ir4 cuboctahedra that share corners with four equivalent ReRe8Ir4 cuboctahedra, corners with eight equivalent IrRe12 cuboctahedra, edges with twenty-four ReRe8Ir4 cuboctahedra, faces with six equivalent IrRe12 cuboctahedra, and faces with twelve ReRe8Ir4 cuboctahedra. All Re–Ir bond lengths are 2.76 Å. Ir is bonded to twelve Re atoms to form IrRe12 cuboctahedra that share corners with four equivalent IrRe12 cuboctahedra, corners with eight equivalent ReRe8Ir4 cuboctahedra, edges with eight equivalent IrRe12 cuboctahedra, edges with sixteen equivalent ReRe8Ir4 cuboctahedra, faces with four equivalent IrRe12 cuboctahedra, and faces with fourteen ReRe8Ir4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3Sn by Materials Project

Re3Sn crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Re sites. In the first Re site, Re is bonded to eight Re and four equivalent Sn atoms to form ReRe8Sn4 cuboctahedra that share corners with twelve equivalent ReRe8Sn4 cuboctahedra, edges with eight equivalent SnRe12 cuboctahedra, edges with sixteen ReRe8Sn4 cuboctahedra, faces with four equivalent SnRe12 cuboctahedra, and faces with fourteen ReRe8Sn4 cuboctahedra. There are four shorter (2.79 Å) and four longer (2.87 Å) Re–Re bond lengths. All Re–Sn bond lengths are 2.87 Å. In the second Re site, Re is bonded to eight equivalent Re and four equivalent Sn atoms to form ReRe8Sn4 cuboctahedra that share corners with four equivalent ReRe8Sn4 cuboctahedra, corners with eight equivalent SnRe12 cuboctahedra, edges with twenty-four ReRe8Sn4 cuboctahedra, faces with six equivalent SnRe12 cuboctahedra, and faces with twelve ReRe8Sn4 cuboctahedra. All Re–Sn bond lengths are 2.79 Å. Sn is bonded to twelve Re atoms to form SnRe12 cuboctahedra that share corners with four equivalent SnRe12 cuboctahedra, corners with eight equivalent ReRe8Sn4 cuboctahedra, edges with eight equivalent SnRe12 cuboctahedra, edges with sixteen equivalent ReRe8Sn4 cuboctahedra, faces with four equivalent SnRe12 cuboctahedra, and faces with fourteen ReRe8Sn4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3Ru by Materials Project

Re3Ru is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Re sites. In the first Re site, Re is bonded to eight Re and four equivalent Ru atoms to form distorted ReRe8Ru4 cuboctahedra that share corners with four equivalent RuRe12 cuboctahedra, corners with fourteen equivalent ReRe8Ru4 cuboctahedra, edges with six equivalent RuRe12 cuboctahedra, edges with twelve ReRe8Ru4 cuboctahedra, faces with four equivalent RuRe12 cuboctahedra, and faces with sixteen ReRe8Ru4 cuboctahedra. There are a spread of Re–Re bond distances ranging from 2.72–2.82 Å. There are two shorter (2.75 Å) and two longer (2.78 Å) Re–Ru bond lengths. In the second Re site, Re is bonded to eight equivalent Re and four equivalent Ru atoms to form distorted ReRe8Ru4 cuboctahedra that share corners with four equivalent RuRe12 cuboctahedra, corners with fourteen ReRe8Ru4 cuboctahedra, edges with six equivalent RuRe12 cuboctahedra, edges with twelve equivalent ReRe8Ru4 cuboctahedra, faces with four equivalent RuRe12 cuboctahedra, and faces with sixteen ReRe8Ru4 cuboctahedra. There are two shorter (2.75 Å) and two longer (2.78 Å) Re–Ru bond lengths. Ru is bonded to twelve Re atoms to form RuRe12 cuboctahedra that share corners with six equivalent RuRe12 cuboctahedra, corners with twelve ReRe8Ru4 cuboctahedra, edges with eighteen ReRe8Ru4 cuboctahedra, faces with eight equivalent RuRe12 cuboctahedra, and faces with twelve ReRe8Ru4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb3Re3B4 by Materials Project

Nb3Re3B4 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded in a 1-coordinate geometry to two equivalent Re and four B atoms. Both Nb–Re bond lengths are 2.71 Å. There are a spread of Nb–B bond distances ranging from 2.36–2.78 Å. In the second Nb site, Nb is bonded in a 6-coordinate geometry to six B atoms. There are two shorter (2.40 Å) and four longer (2.44 Å) Nb–B bond lengths. There are two inequivalent Re sites. In the first Re site, Re is bonded in a 8-coordinate geometry to four equivalent Nb and four equivalent B atoms. All Re–B bond lengths are 2.22 Å. In the second Re site, Re is bonded in a 6-coordinate geometry to six B atoms. There are a spread of Re–B bond distances ranging from 2.27–2.33 Å. There are three inequivalent B sites. In the first B site, B is bonded in a 7-coordinate geometry to two equivalent Nb, four equivalent Re, and one B atom. The B–B bond length is 1.85 Å. In the second B site, B is bonded in a 9-coordinate geometry to four Nb, four equivalent Re, and one B atom. In the third B site, B is bonded in a 9-coordinate geometry to four Nb, four Re, and one B atom. The B–B bond length is 1.99 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsRe2OsSe4Cl3 by Materials Project

CsRe2OsSe4Cl3 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 6-coordinate geometry to six Cl1- atoms. There are a spread of Cs–Cl bond distances ranging from 3.81–3.84 Å. In the second Cs1+ site, Cs1+ is bonded in a distorted cuboctahedral geometry to six Se2- and six Cl1- atoms. There are a spread of Cs–Se bond distances ranging from 3.97–4.01 Å. There are a spread of Cs–Cl bond distances ranging from 4.20–4.24 Å. There are four inequivalent Re6+ sites. In the first Re6+ site, Re6+ is bonded in a 5-coordinate geometry to two Os2-, four Se2-, and one Cl1- atom. Both Re–Os bond lengths are 2.65 Å. There are three shorter (2.54 Å) and one longer (2.55 Å) Re–Se bond lengths. The Re–Cl bond length is 2.41 Å. In the second Re6+ site, Re6+ is bonded in a 5-coordinate geometry to two Os2-, four Se2-, and one Cl1- atom. There are one shorter (2.65 Å) and one longer (2.66 Å) Re–Os bond lengths. There are three shorter (2.54 Å) and one longer (2.55 Å) Re–Se bond lengths. The Re–Cl bond length is 2.41 Å. In the third Re6+ site, Re6+ is bonded in a 5-coordinate geometry to two Os2-, four Se2-, and one Cl1- atom. There are one shorter (2.65 Å) and one longer (2.66 Å) Re–Os bond lengths. There are three shorter (2.54 Å) and one longer (2.55 Å) Re–Se bond lengths. The Re–Cl bond length is 2.41 Å. In the fourth Re6+ site, Re6+ is bonded in a 5-coordinate geometry to two Os2-, four Se2-, and one Cl1- atom. Both Re–Os bond lengths are 2.65 Å. There are three shorter (2.54 Å) and one longer (2.55 Å) Re–Se bond lengths. The Re–Cl bond length is 2.41 Å. There are two inequivalent Os2- sites. In the first Os2- site, Os2- is bonded in a 1-coordinate geometry to four Re6+, four Se2-, and one Cl1- atom. There are a spread of Os–Se bond distances ranging from 2.51–2.53 Å. The Os–Cl bond length is 2.41 Å. In the second Os2- site, Os2- is bonded in a 1-coordinate geometry to four Re6+, four Se2-, and one Cl1- atom. There are a spread of Os–Se bond distances ranging from 2.51–2.53 Å. The Os–Cl bond length is 2.41 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 9-coordinate geometry to two Re6+ and one Os2- atom. In the second Se2- site, Se2- is bonded in a 9-coordinate geometry to two Re6+ and one Os2- atom. In the third Se2- site, Se2- is bonded in a 7-coordinate geometry to one Cs1+, two Re6+, and one Os2- atom. In the fourth Se2- site, Se2- is bonded in a 4-coordinate geometry to one Cs1+, two Re6+, and one Os2- atom. In the fifth Se2- site, Se2- is bonded in a 7-coordinate geometry to one Cs1+, two Re6+, and one Os2- atom. In the sixth Se2- site, Se2- is bonded in a 7-coordinate geometry to one Cs1+, two Re6+, and one Os2- atom. In the seventh Se2- site, Se2- is bonded in a 7-coordinate geometry to one Cs1+, two Re6+, and one Os2- atom. In the eighth Se2- site, Se2- is bonded in a 7-coordinate geometry to one Cs1+, two Re6+, and one Os2- atom. There are six inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Os2- atom. In the second Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re6+ atom. In the third Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re6+ atom. In the fourth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re6+ atom. In the fifth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Os2- atom. In the sixth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3Rh by Materials Project

Re3Rh is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Re sites. In the first Re site, Re is bonded to eight Re and four equivalent Rh atoms to form distorted ReRe8Rh4 cuboctahedra that share corners with four equivalent RhRe12 cuboctahedra, corners with fourteen equivalent ReRe8Rh4 cuboctahedra, edges with six equivalent RhRe12 cuboctahedra, edges with twelve ReRe8Rh4 cuboctahedra, faces with four equivalent RhRe12 cuboctahedra, and faces with sixteen ReRe8Rh4 cuboctahedra. There are six shorter (2.69 Å) and two longer (2.89 Å) Re–Re bond lengths. There are two shorter (2.76 Å) and two longer (2.79 Å) Re–Rh bond lengths. In the second Re site, Re is bonded to eight equivalent Re and four equivalent Rh atoms to form distorted ReRe8Rh4 cuboctahedra that share corners with four equivalent RhRe12 cuboctahedra, corners with fourteen ReRe8Rh4 cuboctahedra, edges with six equivalent RhRe12 cuboctahedra, edges with twelve equivalent ReRe8Rh4 cuboctahedra, faces with four equivalent RhRe12 cuboctahedra, and faces with sixteen ReRe8Rh4 cuboctahedra. There are two shorter (2.76 Å) and two longer (2.79 Å) Re–Rh bond lengths. Rh is bonded to twelve Re atoms to form RhRe12 cuboctahedra that share corners with six equivalent RhRe12 cuboctahedra, corners with twelve ReRe8Rh4 cuboctahedra, edges with eighteen ReRe8Rh4 cuboctahedra, faces with eight equivalent RhRe12 cuboctahedra, and faces with twelve ReRe8Rh4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cs3Re6(SCl)7 by Materials Project

Cs3Re6(SCl)7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are three inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 7-coordinate geometry to two S2- and five Cl1- atoms. There are one shorter (3.59 Å) and one longer (3.79 Å) Cs–S bond lengths. There are a spread of Cs–Cl bond distances ranging from 3.60–3.97 Å. In the second Cs1+ site, Cs1+ is bonded in a 7-coordinate geometry to one S2- and six Cl1- atoms. The Cs–S bond length is 3.78 Å. There are a spread of Cs–Cl bond distances ranging from 3.56–3.96 Å. In the third Cs1+ site, Cs1+ is bonded in a 10-coordinate geometry to five S2- and five Cl1- atoms. There are a spread of Cs–S bond distances ranging from 3.69–4.16 Å. There are a spread of Cs–Cl bond distances ranging from 3.61–4.10 Å. There are six inequivalent Re3+ sites. In the first Re3+ site, Re3+ is bonded to four S2- and one Cl1- atom to form edge-sharing ReS4Cl square pyramids. There are a spread of Re–S bond distances ranging from 2.41–2.43 Å. The Re–Cl bond length is 2.46 Å. In the second Re3+ site, Re3+ is bonded to three S2- and two Cl1- atoms to form edge-sharing ReS3Cl2 square pyramids. There are one shorter (2.38 Å) and two longer (2.42 Å) Re–S bond lengths. There are one shorter (2.45 Å) and one longer (2.53 Å) Re–Cl bond lengths. In the third Re3+ site, Re3+ is bonded to four S2- and one Cl1- atom to form edge-sharing ReS4Cl square pyramids. There are a spread of Re–S bond distances ranging from 2.41–2.43 Å. The Re–Cl bond length is 2.43 Å. In the fourth Re3+ site, Re3+ is bonded to three S2- and two Cl1- atoms to form edge-sharing ReS3Cl2 square pyramids. There are one shorter (2.38 Å) and two longer (2.42 Å) Re–S bond lengths. There are one shorter (2.41 Å) and one longer (2.55 Å) Re–Cl bond lengths. In the fifth Re3+ site, Re3+ is bonded to four S2- and one Cl1- atom to form edge-sharing ReS4Cl square pyramids. There are two shorter (2.42 Å) and two longer (2.43 Å) Re–S bond lengths. The Re–Cl bond length is 2.44 Å. In the sixth Re3+ site, Re3+ is bonded to three S2- and two Cl1- atoms to form edge-sharing ReS3Cl2 square pyramids. There are one shorter (2.37 Å) and two longer (2.42 Å) Re–S bond lengths. There are one shorter (2.41 Å) and one longer (2.56 Å) Re–Cl bond lengths. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three Re3+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three Re3+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to one Cs1+ and three Re3+ atoms. In the fourth S2- site, S2- is bonded in a 4-coordinate geometry to one Cs1+ and three Re3+ atoms. In the fifth S2- site, S2- is bonded in a 5-coordinate geometry to two Cs1+ and three Re3+ atoms. In the sixth S2- site, S2- is bonded in a 5-coordinate geometry to two Cs1+ and three Re3+ atoms. In the seventh S2- site, S2- is bonded in a 4-coordinate geometry to two Cs1+ and three Re3+ atoms. There are seven inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 1-coordinate geometry to three Cs1+ and one Re3+ atom. In the second Cl1- site, Cl1- is bonded in a distorted single-bond geometry to three Cs1+ and one Re3+ atom. In the third Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re3+ atom. In the fourth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re3+ atom. In the fifth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re3+ atom. In the sixth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re3+ atom. In the seventh Cl1- site, Cl1- is bonded in a 4-coordinate geometry to two Cs1+ and three Re3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CrRe5B2 by Materials Project

CrRe5B2 crystallizes in the orthorhombic Amm2 space group. The structure is two-dimensional and consists of two CrRe5B2 sheets oriented in the (0, 1, 0) direction. Cr is bonded in a distorted L-shaped geometry to two equivalent B atoms. Both Cr–B bond lengths are 2.15 Å. There are three inequivalent Re sites. In the first Re site, Re is bonded in a 2-coordinate geometry to three B atoms. There are two shorter (2.27 Å) and one longer (2.57 Å) Re–B bond lengths. In the second Re site, Re is bonded in a 3-coordinate geometry to three B atoms. There are two shorter (2.26 Å) and one longer (2.41 Å) Re–B bond lengths. In the third Re site, Re is bonded in a distorted L-shaped geometry to two equivalent B atoms. Both Re–B bond lengths are 2.25 Å. There are two inequivalent B sites. In the first B site, B is bonded in a 2-coordinate geometry to two equivalent Cr and six Re atoms. In the second B site, B is bonded in a 6-coordinate geometry to eight Re atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re2P3N2(Cl5O)3 by Materials Project

(RePNOCl6)2POCl3 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four phosphorus oxychloride molecules and two RePNOCl6 clusters. In one of the RePNOCl6 clusters, there are two inequivalent Re6+ sites. In the first Re6+ site, Re6+ is bonded to two N3-, one O2-, and three Cl1- atoms to form distorted ReN2Cl3O octahedra that share a cornercorner with one PCl3O tetrahedra. There is one shorter (1.72 Å) and one longer (2.04 Å) Re–N bond length. The Re–O bond length is 2.38 Å. There are one shorter (2.31 Å) and two longer (2.33 Å) Re–Cl bond lengths. In the second Re6+ site, Re6+ is bonded in a 6-coordinate geometry to two N3-, one O2-, and three Cl1- atoms. There is one shorter (1.71 Å) and one longer (2.01 Å) Re–N bond length. The Re–O bond length is 2.55 Å. There are a spread of Re–Cl bond distances ranging from 2.31–2.34 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to one O2- and three Cl1- atoms to form PCl3O tetrahedra that share a cornercorner with one ReN2Cl3O octahedra. The corner-sharing octahedral tilt angles are 27°. The P–O bond length is 1.49 Å. There is two shorter (1.99 Å) and one longer (2.00 Å) P–Cl bond length. In the second P5+ site, P5+ is bonded in a tetrahedral geometry to one O2- and three Cl1- atoms. The P–O bond length is 1.49 Å. There is two shorter (1.99 Å) and one longer (2.00 Å) P–Cl bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a linear geometry to two Re6+ atoms. In the second N3- site, N3- is bonded in a linear geometry to two Re6+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Re6+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Re6+ and one P5+ atom. There are twelve inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the fifth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the sixth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the seventh Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the eighth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the ninth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the tenth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the eleventh Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the twelfth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In one of the RePNOCl6 clusters, there are two inequivalent Re6+ sites. In the first Re6+ site, Re6+ is bonded to two N3-, one O2-, and three Cl1- atoms to form distorted ReN2Cl3O octahedra that share corners with two equivalent ReN2Cl3O octahedra and a cornercorner with one PCl3O tetrahedra. The corner-sharing octahedra tilt angles range from 4–8°. There is one shorter (1.71 Å) and one longer (2.01 Å) Re–N bond length. The Re–O bond length is 2.42 Å. There are a spread of Re–Cl bond distances ranging from 2.32–2.34 Å. In the second Re6+ site, Re6+ is bonded to two N3-, one O2-, and three Cl1- atoms to form distorted ReN2Cl3O octahedra that share corners with two equivalent ReN2Cl3O octahedra and a cornercorner with one PCl3O tetrahedra. The corner-sharing octahedra tilt angles range from 4–8°. There is one shorter (1.71 Å) and one longer (2.02 Å) Re–N bond length. The Re–O bond length is 2.40 Å. There are one shorter (2.32 Å) and two longer (2.33 Å) Re–Cl bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to one O2- and three Cl1- atoms to form PCl3O tetrahedra that share a cornercorner with one ReN2Cl3O octahedra. The corner-sharing octahedral tilt angles are 27°. The P–O bond length is 1.49 Å. There is two shorter (1.99 Å) and one longer (2.00 Å) P–Cl bond length. In the second P5+ site, P5+ is bonded to one O2- and three Cl1- atoms to form PCl3O tetrahedra that share a cornercorner with one ReN2Cl3O octahedra. The corner-sharing octahedral tilt angles are 22°. The P–O bond length is 1.48 Å. There is one shorter (1.99 Å) and two longer (2.00 Å) P–Cl bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a linear geometry to two Re6+ atoms. In the second N3- site, N3- is bonded in a linear geometry to two Re6+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Re6+ and one P5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one Re6+ and one P5+ atom. There are twelve inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the fifth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the sixth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the seventh Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the eighth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the ninth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the tenth Cl1- site, Cl1- is bonded in a single-bond geometry to one Re6+ atom. In the eleventh Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the twelfth Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Concentration‐Discharge Relationships of Dissolved Rhenium in Alpine Catchments Reveal Its Use as a Tracer of Oxidative Weathering

Abstract Oxidative weathering of sedimentary rocks plays an important role in the global carbon cycle. Rhenium (Re) has been proposed as a tracer of rock organic carbon (OC petro ) oxidation. However, the sources of Re and its mobilization by hydrological processes remain poorly constrained. Here, we examine dissolved Re as a function of water discharge, using samples collected from three alpine catchments that drain sedimentary rocks in Switzerland (Erlenbach and Vogelbach) and Colorado, USA (East River). The Swiss catchments reveal a higher dissolved Re flux in the catchment with higher erosion rates, but have similar [Re]/[Na + ] and [Re]/[SO 4 2− ] ratios, which indicate a dominance of Re from OC petro . Despite differences in rock type and hydro‐climatic setting, the three catchments have a positive correlation between river water [Re]/[Na + ] and [Re]/[SO 4 2− ] and water discharge. We propose that this reflects preferential routing of Re from a near‐surface, oxidative weathering zone. The observations support the use of Re as a proxy to trace rock‐organic carbon oxidation, and suggest it may be a hydrological tracer of vadose zone processes. We apply the Re proxy and estimate CO 2 release by OC petro oxidation of 5.7 +6.6 / −2.0 tC km −2 yr −1 for the Erlenbach. The overall weathering intensity was ∼40%, meaning that the corresponding export of unweathered OC petro in river sediments is large, and the findings call for more measurements of OC petro oxidation in mountains and rivers as they cross floodplains.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Runaway electron beam dynamics at low plasma density in DIII-D: energy distribution, current profile, and internal instability

Parameters of the post-disruption runaway electron (RE) beam in the collisionless background plasma achieved after deuterium injection are investigated in DIII-D. The spatially resolved RE energy distribution function is measured for the first time during the RE plateau stage by inverting hard X-ray bremsstrahlung spectra. It has maximum energy up to 20 MeV and a non-monotonous feature at 5{6 MeV observed only in the core of the beam supporting the possibility of kinetic instabilities. The RE current profile is reconstructed for the first time using the spatially resolved RE energy distribution. It is found to be more peaked than the pre-disruption plasma current, with higher internal inductance, suggesting preferential formation of REs in the core plasma or potentially a radially inward motion of the REs. The accessed relatively low-current (180 kA) RE beam is found stable, likely due to its elevated q profile. From this base stable equilibrium, instability is accessed by ramping the solenoid current. Under a large applied accelerating loop voltage an internal kink mode is observed. The kink mode leads to sawtooth-like relaxation of the RE current profile, but drives no RE loss. Under conditions of a large decelerating voltage, chirping Alfvénic instabilities driven by REs during the RE plateau stage are observed for the first time. The low-frequency (0.1{7 MHz) Alfvénic instabilities, supposedly compressional Alfvén eigenmodes, are found to be correlated with a RE loss signal. Finally, this provides novel plasma conditions to study these instabilities and investigate opportunities to utilize them for RE control. Bifurcated electron cyclotron emission (ECE) spectrum is measured during the collisionless RE plateau, with a break point at ≈100 GHz suggesting resonant absorption of the ECE at low frequencies.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2023

Cross-machine comparison of runaway electron generation during tokamak start-up for extrapolation to ITER

A cross-machine comparison of global parameters that determine the runaway electron (RE) generation and loss process during tokamak start-up was carried out with the aim to extrapolate these to ITER. The study found that all considered discharges, also those that do not show signs of RE, are non-thermal at the start, i.e. have a streaming parameter larger than 0.1. During the current ramp-up the electric field, E, remains above the critical value, E c , that allows RE in the plasma. The distinction to be made is not if RE can form but, if sufficient RE can form fast enough such that they are detected or start to dominate the dynamics of the tokamak discharge. The dynamics of the value of E, density and temperature during tokamak are key to the formation of RE. It was found that larger devices operate with E closer to E c , due to their higher temperatures, hence the RE generation is relatively slower. The slower time scales for the formation of RE, estimated to be of the order of 100s of ms in ITER simplifies the development of avoidance schemes. The RE confinement time is also an important determinant of the entire process and is found to increase with the device size. The study also revealed that drift orbit losses, a mechanism often attributed as the main RE loss mechanism during the early tokamak discharge, are actually more difficult to achieve. RE losses might be more likely attributed to RE diffusion due to magnetic turbulence.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2026

Modeling the effect of MHD activity on runaway electron generation during SPARC disruptions

Magnetohydrodynamic (MHD) instabilities and runaway electrons (REs) interact in several ways, making it important to self-consistently model these interactions for accurate predictions of RE generation and the design of mitigation strategies, such as massive gas injection (MGI). Using M3D-C1 – an extended MHD code with a RE fluid model – we investigate the effects of 3-D nonlinear MHD activity, material injection, and 2-D axisymmetric vertical displacement events (VDEs) on RE evolution during disruptions on SPARC – a high-field, high-current tokamak designed to achieve a fusion gain Q > 1. Several cases, comprising different combinations of neon (Ne) and deuterium (D 2 ) injection, are considered. Here, our results demonstrate key effects that arise from the self-consistent RE + MHD coupling, such as an initial increase in RE generation due to MHD instability growth, decreased saturation energies of the m/n = 1/1 mode driving sawteeth-like activity, RE losses in stochastic magnetic fields, and subsequent RE confinement and plateau formation due to re-healing of flux surfaces. Large RE plateaus (>5 MA) are obtained with Ne-only injection (2-5 × 10 21 atoms), while combined D 2 + Ne injection (2 × 10 21 Ne atoms; 1.8 × 10 22 D 2 molecules) produces a lower RE current (<2 MA). With D 2 + Ne injection, a post thermal quench "cold" VDE terminates the RE beam, preventing a steady plateau. These simulations couple REs, 3-D MHD instabilities, MGI, and axisymmetric VDEs for the first time in SPARC disruption simulations and represent a crucial step in understanding RE generation and mitigation in high-current devices like SPARC.

Datta, Rishabh [Massachusetts Inst. of Technology ↗
DOE OSTI2020

Materials Data on Re3Ge7 by Materials Project

Re3Ge7 is Magnesium tetraboride-like structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Re sites. In the first Re site, Re is bonded in a 9-coordinate geometry to nine Ge atoms. There are a spread of Re–Ge bond distances ranging from 2.57–2.90 Å. In the second Re site, Re is bonded in a 8-coordinate geometry to eight Ge atoms. There are a spread of Re–Ge bond distances ranging from 2.54–2.68 Å. There are four inequivalent Ge sites. In the first Ge site, Ge is bonded in a 3-coordinate geometry to three equivalent Re and four equivalent Ge atoms. All Ge–Ge bond lengths are 3.05 Å. In the second Ge site, Ge is bonded in a 5-coordinate geometry to five equivalent Re atoms. In the third Ge site, Ge is bonded in a 4-coordinate geometry to three Re and three equivalent Ge atoms. There are one shorter (2.49 Å) and two longer (2.76 Å) Ge–Ge bond lengths. In the fourth Ge site, Ge is bonded in a 3-coordinate geometry to three Re and five Ge atoms.

36 MATERIALS SCIENCE↗