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DOE OSTI2020

Materials Data on Y8Cu3(GeSe7)3 by Materials Project

Y8Cu3(GeSe7)3 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are eight inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 7-coordinate geometry to eight Se2- atoms. There are a spread of Y–Se bond distances ranging from 2.91–3.50 Å. In the second Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Y–Se bond distances ranging from 2.87–3.06 Å. In the third Y3+ site, Y3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Y–Se bond distances ranging from 2.84–3.38 Å. In the fourth Y3+ site, Y3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Y–Se bond distances ranging from 2.91–3.46 Å. In the fifth Y3+ site, Y3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Y–Se bond distances ranging from 2.89–3.22 Å. In the sixth Y3+ site, Y3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Y–Se bond distances ranging from 2.84–3.35 Å. In the seventh Y3+ site, Y3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Y–Se bond distances ranging from 2.88–3.42 Å. In the eighth Y3+ site, Y3+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Y–Se bond distances ranging from 2.89–3.13 Å. There are three inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a trigonal planar geometry to three Se2- atoms. There are a spread of Cu–Se bond distances ranging from 2.36–2.38 Å. In the second Cu2+ site, Cu2+ is bonded in a trigonal planar geometry to three Se2- atoms. There are two shorter (2.34 Å) and one longer (2.38 Å) Cu–Se bond lengths. In the third Cu2+ site, Cu2+ is bonded in a trigonal planar geometry to three Se2- atoms. There are one shorter (2.36 Å) and two longer (2.37 Å) Cu–Se bond lengths. There are three inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are a spread of Ge–Se bond distances ranging from 2.34–2.42 Å. In the second Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are a spread of Ge–Se bond distances ranging from 2.37–2.41 Å. In the third Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are a spread of Ge–Se bond distances ranging from 2.39–2.43 Å. There are twenty-one inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Y3+ and one Ge4+ atom. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Y3+ and one Ge4+ atom. In the third Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Y3+ and one Ge4+ atom. In the fourth Se2- site, Se2- is bonded in a 3-coordinate geometry to two Y3+ and one Ge4+ atom. In the fifth Se2- site, Se2- is bonded in a 3-coordinate geometry to two Y3+ and one Ge4+ atom. In the sixth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Y3+ and one Ge4+ atom. In the seventh Se2- site, Se2- is bonded in a 3-coordinate geometry to two Y3+ and one Ge4+ atom. In the eighth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Y3+ and one Ge4+ atom. In the ninth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Y3+ and one Ge4+ atom. In the tenth Se2- site, Se2- is bonded in a distorted tetrahedral geometry to three Y3+ and one Ge4+ atom. In the eleventh Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to two Y3+ and one Ge4+ atom. In the twelfth Se2- site, Se2- is bonded in a tetrahedral geometry to three Y3+ and one Ge4+ atom. In the thirteenth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Y3+ and one Cu2+ atom. In the fourteenth Se2- site, Se2- is bonded in a 1-coordinate geometry to four Y3+ and one Cu2+ atom. In the fifteenth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Y3+ and one Cu2+ atom. In the sixteenth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Y3+ and one Cu2+ atom. In the seventeenth Se2- site, Se2- is bonded in a 1-coordinate geometry to four Y3+ and one Cu2+ atom. In the eighteenth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Y3+ and one Cu2+ atom. In the nineteenth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Y3+ and one Cu2+ atom. In the twentieth Se2- site, Se2- is bonded in a 4-coordinate geometry to four Y3+ and one Cu2+ atom. In the twenty-first Se2- site, Se2- is bonded in a 4-coordinate geometry to three Y3+ and one Cu2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ErSe2NO11 by Materials Project

ErNSe2O9O2 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of two hydrogen peroxide molecules and one ErNSe2O9 sheet oriented in the (0, 0, 1) direction. In the ErNSe2O9 sheet, Er is bonded to six O atoms to form ErO6 octahedra that share corners with three equivalent SeO4 tetrahedra. There are a spread of Er–O bond distances ranging from 2.18–2.29 Å. N is bonded in a water-like geometry to two O atoms. There is one shorter (1.17 Å) and one longer (1.55 Å) N–O bond length. There are two inequivalent Se sites. In the first Se site, Se is bonded to four O atoms to form SeO4 tetrahedra that share corners with three equivalent ErO6 octahedra. The corner-sharing octahedra tilt angles range from 35–56°. There are a spread of Se–O bond distances ranging from 1.67–2.01 Å. In the second Se site, Se is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Se–O bond distances ranging from 1.68–1.88 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Er and one Se atom. In the second O site, O is bonded in a single-bond geometry to one N atom. In the third O site, O is bonded in a water-like geometry to one Se and one O atom. The O–O bond length is 1.35 Å. In the fourth O site, O is bonded in a bent 120 degrees geometry to one Er and one O atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Er and one Se atom. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Er and one Se atom. In the seventh O site, O is bonded in a bent 150 degrees geometry to one Er and one Se atom. In the eighth O site, O is bonded in a bent 120 degrees geometry to one N and one Se atom. In the ninth O site, O is bonded in a bent 150 degrees geometry to one Er and one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cd2Se3N2O15 by Materials Project

Cd2Se3O14N2O crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional and consists of two hydroxylamine, o-amino- molecules and one Cd2Se3O14 framework. In the Cd2Se3O14 framework, Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with five SeO4 tetrahedra. There are a spread of Cd–O bond distances ranging from 2.26–2.39 Å. There are two inequivalent Se+5.33+ sites. In the first Se+5.33+ site, Se+5.33+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with two equivalent CdO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Se–O bond distances ranging from 1.64–1.74 Å. In the second Se+5.33+ site, Se+5.33+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with four equivalent CdO6 octahedra. The corner-sharing octahedra tilt angles range from 51–55°. There is one shorter (1.67 Å) and three longer (1.68 Å) Se–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Cd2+ and one Se+5.33+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Cd2+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Se+5.33+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Se+5.33+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cd2+ and one Se+5.33+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Cd2+ and one Se+5.33+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Cd2+ and one Se+5.33+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cd2+ and one Se+5.33+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaSe2O9 by Materials Project

LaSe2O9 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. La is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of La–O bond distances ranging from 2.39–2.77 Å. There are two inequivalent Se sites. In the first Se site, Se is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Se–O bond distances ranging from 1.66–1.73 Å. In the second Se site, Se is bonded in a tetrahedral geometry to four O atoms. There are a spread of Se–O bond distances ranging from 1.67–1.69 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one La and one Se atom. In the second O site, O is bonded in a single-bond geometry to one Se atom. In the third O site, O is bonded in a single-bond geometry to one La atom. In the fourth O site, O is bonded in a single-bond geometry to one Se atom. In the fifth O site, O is bonded in a single-bond geometry to one La atom. In the sixth O site, O is bonded in a 2-coordinate geometry to two equivalent La and one Se atom. In the seventh O site, O is bonded in a distorted trigonal planar geometry to two equivalent La and one Se atom. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to one La and one Se atom. In the ninth O site, O is bonded in a distorted bent 150 degrees geometry to one La and one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Rb3Yb7Se12 by Materials Project

Rb3Yb7Se12 is Orthorhombic Perovskite-like structured and crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. there are three inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are a spread of Rb–Se bond distances ranging from 3.51–3.97 Å. In the second Rb1+ site, Rb1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Rb–Se bond distances ranging from 3.52–4.17 Å. In the third Rb1+ site, Rb1+ is bonded to six Se2- atoms to form distorted RbSe6 octahedra that share edges with two equivalent RbSe6 octahedra and edges with four YbSe6 octahedra. There are a spread of Rb–Se bond distances ranging from 3.41–3.90 Å. There are seven inequivalent Yb3+ sites. In the first Yb3+ site, Yb3+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Yb–Se bond distances ranging from 2.81–2.96 Å. In the second Yb3+ site, Yb3+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are a spread of Yb–Se bond distances ranging from 2.80–3.47 Å. In the third Yb3+ site, Yb3+ is bonded in a 4-coordinate geometry to six Se2- atoms. There are a spread of Yb–Se bond distances ranging from 2.78–3.41 Å. In the fourth Yb3+ site, Yb3+ is bonded in a 4-coordinate geometry to six Se2- atoms. There are a spread of Yb–Se bond distances ranging from 2.77–3.47 Å. In the fifth Yb3+ site, Yb3+ is bonded to six Se2- atoms to form edge-sharing YbSe6 octahedra. There are a spread of Yb–Se bond distances ranging from 2.82–3.06 Å. In the sixth Yb3+ site, Yb3+ is bonded to six Se2- atoms to form distorted YbSe6 octahedra that share edges with two equivalent RbSe6 octahedra and edges with two equivalent YbSe6 octahedra. There are a spread of Yb–Se bond distances ranging from 2.88–3.52 Å. In the seventh Yb3+ site, Yb3+ is bonded to six Se2- atoms to form distorted YbSe6 octahedra that share edges with two equivalent RbSe6 octahedra and edges with two equivalent YbSe6 octahedra. There are a spread of Yb–Se bond distances ranging from 2.86–3.44 Å. There are twelve inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to three Rb1+ and three Yb3+ atoms. In the second Se2- site, Se2- is bonded to two equivalent Rb1+ and three Yb3+ atoms to form distorted SeRb2Yb3 square pyramids that share corners with two equivalent SeRb3Yb3 octahedra and edges with two equivalent SeRb2Yb3 square pyramids. The corner-sharing octahedral tilt angles are 72°. In the third Se2- site, Se2- is bonded to one Rb1+ and five Yb3+ atoms to form distorted SeRbYb5 square pyramids that share corners with two equivalent SeRb3Yb3 octahedra, an edgeedge with one SeRb3Yb3 octahedra, and edges with two equivalent SeRbYb5 square pyramids. The corner-sharing octahedral tilt angles are 11°. In the fourth Se2- site, Se2- is bonded in a 6-coordinate geometry to one Rb1+ and five Yb3+ atoms. In the fifth Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Rb1+ and three Yb3+ atoms. In the sixth Se2- site, Se2- is bonded in a 5-coordinate geometry to two equivalent Rb1+ and three Yb3+ atoms. In the seventh Se2- site, Se2- is bonded in a 6-coordinate geometry to three Rb1+ and three Yb3+ atoms. In the eighth Se2- site, Se2- is bonded to three Rb1+ and three Yb3+ atoms to form distorted SeRb3Yb3 octahedra that share corners with four SeRb2Yb3 square pyramids, edges with two equivalent SeRb3Yb3 octahedra, and an edgeedge with one SeRbYb5 square pyramid. In the ninth Se2- site, Se2- is bonded in a 2-coordinate geometry to one Rb1+, two Yb3+, and two equivalent Se2- atoms. Both Se–Se bond lengths are 2.53 Å. In the tenth Se2- site, Se2- is bonded in a 2-coordinate geometry to one Rb1+, four Yb3+, and two equivalent Se2- atoms. Both Se–Se bond lengths are 2.52 Å. In the eleventh Se2- site, Se2- is bonded in a 5-coordinate geometry to three Yb3+ and two equivalent Se2- atoms. In the twelfth Se2- site, Se2- is bonded in a 5-coordinate geometry to three Yb3+ and two equivalent Se2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta2Se8Br by Materials Project

Ta2Se8Br crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Ta+4.50+ sites. In the first Ta+4.50+ site, Ta+4.50+ is bonded to eight Se1- atoms to form face-sharing TaSe8 hexagonal bipyramids. There are a spread of Ta–Se bond distances ranging from 2.57–2.80 Å. In the second Ta+4.50+ site, Ta+4.50+ is bonded to seven Se1- and one Br1- atom to form distorted face-sharing TaSe7Br hexagonal bipyramids. There are a spread of Ta–Se bond distances ranging from 2.61–2.74 Å. The Ta–Br bond length is 2.66 Å. In the third Ta+4.50+ site, Ta+4.50+ is bonded to eight Se1- atoms to form face-sharing TaSe8 hexagonal bipyramids. There are a spread of Ta–Se bond distances ranging from 2.59–2.77 Å. In the fourth Ta+4.50+ site, Ta+4.50+ is bonded to eight Se1- atoms to form face-sharing TaSe8 hexagonal bipyramids. There are a spread of Ta–Se bond distances ranging from 2.60–2.74 Å. There are sixteen inequivalent Se1- sites. In the first Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ atoms. In the second Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ atoms. In the third Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ atoms. In the fourth Se1- site, Se1- is bonded in a 1-coordinate geometry to one Ta+4.50+ atom. In the fifth Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ and one Se1- atom. The Se–Se bond length is 2.39 Å. In the sixth Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ and one Se1- atom. The Se–Se bond length is 2.40 Å. In the seventh Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ atoms. In the eighth Se1- site, Se1- is bonded in a 1-coordinate geometry to two Ta+4.50+, one Se1-, and one Br1- atom. The Se–Br bond length is 3.16 Å. In the ninth Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ atoms. In the tenth Se1- site, Se1- is bonded in a 3-coordinate geometry to two Ta+4.50+ and one Br1- atom. The Se–Br bond length is 3.12 Å. In the eleventh Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+, one Se1-, and one Br1- atom. The Se–Se bond length is 2.41 Å. The Se–Br bond length is 3.10 Å. In the twelfth Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ atoms. In the thirteenth Se1- site, Se1- is bonded in a 1-coordinate geometry to two Ta+4.50+, one Se1-, and one Br1- atom. The Se–Br bond length is 3.13 Å. In the fourteenth Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ and one Se1- atom. In the fifteenth Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ atoms. In the sixteenth Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ atoms. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 1-coordinate geometry to one Ta+4.50+ atom. In the second Br1- site, Br1- is bonded in a 4-coordinate geometry to four Se1- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GdSe2NO11 by Materials Project

Gd(SeO4)2NOO2 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of two hydrogen peroxide molecules; two nitroxyl molecules; and one Gd(SeO4)2 sheet oriented in the (0, 0, 1) direction. In the Gd(SeO4)2 sheet, Gd is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Gd–O bond distances ranging from 2.26–2.46 Å. There are two inequivalent Se sites. In the first Se site, Se is bonded in a tetrahedral geometry to four O atoms. There are a spread of Se–O bond distances ranging from 1.66–1.69 Å. In the second Se site, Se is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Se–O bond distances ranging from 1.67–1.72 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Gd and one Se atom. In the second O site, O is bonded in a single-bond geometry to one Se atom. In the third O site, O is bonded in a single-bond geometry to one Gd atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to one Gd and one Se atom. In the fifth O site, O is bonded in a distorted bent 120 degrees geometry to one Gd and one Se atom. In the sixth O site, O is bonded in a bent 150 degrees geometry to one Gd and one Se atom. In the seventh O site, O is bonded in a single-bond geometry to one Se atom. In the eighth O site, O is bonded in a bent 120 degrees geometry to one Gd and one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K5In3P6Se19 by Materials Project

K5In3P6Se19 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are five inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 9-coordinate geometry to seven Se2- atoms. There are a spread of K–Se bond distances ranging from 3.37–3.74 Å. In the second K1+ site, K1+ is bonded in a 9-coordinate geometry to eight Se2- atoms. There are a spread of K–Se bond distances ranging from 3.39–3.92 Å. In the third K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of K–Se bond distances ranging from 3.36–3.77 Å. In the fourth K1+ site, K1+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are a spread of K–Se bond distances ranging from 3.35–3.56 Å. In the fifth K1+ site, K1+ is bonded in a 9-coordinate geometry to eight Se2- atoms. There are a spread of K–Se bond distances ranging from 3.41–3.98 Å. There are three inequivalent In1+ sites. In the first In1+ site, In1+ is bonded to six Se2- atoms to form corner-sharing InSe6 octahedra. There are a spread of In–Se bond distances ranging from 2.74–2.93 Å. In the second In1+ site, In1+ is bonded in a rectangular see-saw-like geometry to four Se2- atoms. There are a spread of In–Se bond distances ranging from 2.59–2.70 Å. In the third In1+ site, In1+ is bonded to five Se2- atoms to form corner-sharing InSe5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 56°. There are a spread of In–Se bond distances ranging from 2.66–3.04 Å. There are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are a spread of P–Se bond distances ranging from 2.15–2.26 Å. In the second P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are a spread of P–Se bond distances ranging from 2.15–2.26 Å. In the third P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are one shorter (2.16 Å) and two longer (2.26 Å) P–Se bond lengths. In the fourth P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are two shorter (2.17 Å) and one longer (2.24 Å) P–Se bond lengths. In the fifth P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are a spread of P–Se bond distances ranging from 2.15–2.27 Å. In the sixth P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se2- atoms. There are a spread of P–Se bond distances ranging from 2.20–2.24 Å. There are nineteen inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to one K1+ and three In1+ atoms. In the second Se2- site, Se2- is bonded in a 4-coordinate geometry to two K1+, one In1+, and one P5+ atom. In the third Se2- site, Se2- is bonded in a 4-coordinate geometry to two K1+, one In1+, and one P5+ atom. In the fourth Se2- site, Se2- is bonded in a 1-coordinate geometry to three K1+ and one P5+ atom. In the fifth Se2- site, Se2- is bonded in a 2-coordinate geometry to one K1+, one In1+, and one P5+ atom. In the sixth Se2- site, Se2- is bonded in a 2-coordinate geometry to one K1+, one In1+, and one P5+ atom. In the seventh Se2- site, Se2- is bonded in a 1-coordinate geometry to two K1+ and one P5+ atom. In the eighth Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent K1+, one In1+, and one P5+ atom. In the ninth Se2- site, Se2- is bonded in a 3-coordinate geometry to one K1+, one In1+, and one P5+ atom. In the tenth Se2- site, Se2- is bonded in a 4-coordinate geometry to three K1+ and one P5+ atom. In the eleventh Se2- site, Se2- is bonded in a 2-coordinate geometry to one K1+, one In1+, and one P5+ atom. In the twelfth Se2- site, Se2- is bonded in a 1-coordinate geometry to three K1+ and one P5+ atom. In the thirteenth Se2- site, Se2- is bonded in a 1-coordinate geometry to three K1+ and one P5+ atom. In the fourteenth Se2- site, Se2- is bonded in a 4-coordinate geometry to two K1+, one In1+, and one P5+ atom. In the fifteenth Se2- site, Se2- is bonded in a 3-coordinate geometry to two K1+ and one P5+ atom. In the sixteenth Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent K1+, one In1+, and one P5+ atom. In the seventeenth Se2- site, Se2- is bonded in a 1-coordinate geometry to two equivalent K1+, one In1+, and one P5+ atom. In the eighteenth Se2- site, Se2- is bonded in a 2-coordinate geometry to one K1+, one In1+, and one P5+ atom. In the nineteenth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to two K1+, one In1+, and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TmSe2NO11 by Materials Project

TmNSe2O9O2 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of two hydrogen peroxide molecules and one TmNSe2O9 sheet oriented in the (0, 0, 1) direction. In the TmNSe2O9 sheet, Tm is bonded to six O atoms to form TmO6 octahedra that share corners with three equivalent SeO4 tetrahedra. There are a spread of Tm–O bond distances ranging from 2.17–2.27 Å. N is bonded in a water-like geometry to two O atoms. There is one shorter (1.17 Å) and one longer (1.56 Å) N–O bond length. There are two inequivalent Se sites. In the first Se site, Se is bonded to four O atoms to form SeO4 tetrahedra that share corners with three equivalent TmO6 octahedra. The corner-sharing octahedra tilt angles range from 35–57°. There are a spread of Se–O bond distances ranging from 1.67–1.99 Å. In the second Se site, Se is bonded in a trigonal non-coplanar geometry to three O atoms. There is two shorter (1.69 Å) and one longer (1.87 Å) Se–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Tm and one Se atom. In the second O site, O is bonded in a single-bond geometry to one N atom. In the third O site, O is bonded in a water-like geometry to one Se and one O atom. The O–O bond length is 1.36 Å. In the fourth O site, O is bonded in a bent 120 degrees geometry to one Tm and one O atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Tm and one Se atom. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Tm and one Se atom. In the seventh O site, O is bonded in a bent 150 degrees geometry to one Tm and one Se atom. In the eighth O site, O is bonded in a water-like geometry to one N and one Se atom. In the ninth O site, O is bonded in a bent 150 degrees geometry to one Tm and one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Characterization of Arsenic and Selenium in Coal Fly Ash to Improve Evaluations for Disposal and Reuse Potential (Final Technical Report)

Coal fly ash is a high volume waste material that is discarded in landfills and surface water impoundments across the U.S. and is also widely recycled for a variety of applications. The leaching of potential of contaminants of concern, such as arsenic (As) and selenium (Se), is often the driver of risk assessments for coal ash disposal and reuse. The extent of leachable As and Se depends on several factors related to environmental conditions and fly ash characteristics. Previous studies employed various methods to delineate the concentration, chemical form, and distribution of As and Se in fly ash materials. However, few studies have attempted to directly correlate these properties to mobilization parameters relevant to disposal and reuse. Instead, the coal residuals industries often rely upon standardized leaching protocols that can be laborious or involve hazardous chemicals. The goals of the project were to: 1) Develop and evaluate a characterization protocol that can be used to screen fly ash samples for leachability of As and Se; 2) Characterize As, Se, and associated constituents of fly ash particles at multiple length scales (nanometer to micrometer) to determine if elemental associations differ as a function of the resolution of characterization; and 3) Establish a predictive model for the chemical composition of coal ash produced annually at major U.S. coal fired power facilities on 50-year national coal supply records. For the first objective, we performed leaching experiments with 52 fly ash samples collected from 15 different U.S. power plants and representing coal feedstocks from the three major domestic coal regions. For this work, we assessed the mobilization potential of As and Se in fly ash based on standardized leaching protocols and performed multivariate and lasso regression analyses to explore correlations of leachable As and Se contents with characteristics such as major element contents, loss on ignition (LOI) and pH. The results of regression models indicated that major elements (Fe, Ca, Al) for a wide range of fly ashes can serve as predictor variables for the leaching potential of As, but not for Se. LOI and pH were not important predictive variables in the models. Both regression approaches resulted in relatively strong fits for leachable As (correlation coefficient R 2 = 0.78 for both models) compared to models for leachable Se (R 2 = 0.49). Overall, these results suggest that correlation models combined with on-site elemental analysis with portable analyzers may enable a screening method for leachable As in coal ash. For the second objective, we utilized nanoscale 2-D imaging (30-50 nm spot size) with the Hard X-ray Nanoprobe (HXN) in combination with microprobe X-ray capabilities (~5 µm resolution) to determine As and Se elemental associations in fly ash particles. Speciation of As and Se was also measured at the nano- to microscale with X-ray absorption spectroscopy. The enhanced resolution of HXN showed As and Se that were diffusely located around or comingled with Ca- and Fe-rich particles. The results also showed nanoparticles of Se attached to the surface of fly ash grains. Overall, a comparison of As and Se species across scales highlights the heterogeneity and complexity of chemical associations for these trace elements of concern in coal fly ash. For the final objective, we developed a predictive model for major element composition of coal ash in reserve at disposal sites of major U.S. coal fired power plants. This model was constructed from coal purchase records of 705 power stations from 1973-2022 and was trained on coal ash composition data showing that coal ash elemental composition is strongly associated with the source of feedstock coal. The model showed regional shifts in the major element contents of ash produced by power plants in the last 50 years, particularly for calcium and iron (expressed as %CaO and %Fe 2 O 3 ), as coal-fired power stations changed their source of coal over this time frame. Our approach enables an estimation of coal ash chemical composition that is stored in waste impoundments at individual power stations. Such information can help delineate the regional market potential for material applications that would utilize coal ash harvested from disposal sites across the U.S.

01 COAL, LIGNITE, AND PEAT↗
NASA NTRSDate not supplied

Introduction of an Agile Systems Engineering Process to the NASA Armstrong Flight Research Center

This paper will provide background on the National Aeronautics and Space Administration (NASA) Aeronautics Research Mission Directorate (ARMD) ARMD Test Data Portal (ATDP) effort along with the rationale that motivated the ATDP team to consider implementing an agile systems engineering (SE) process. The primary motivation for using this new SE process was based on the desire to mitigate a major risk to project success. Since the agile SE process had never been used before at the NASA Armstrong Flight Research Center (AFRC), utilizing this new SE process required a trailblazing effort to introduce it to NASA AFRC leadership. As a result, the ATDP team chose to adhere to the agile SE process in addition to the trusted classical waterfall SE process on ATDP. Through successful execution of this hybrid SE process during Phase I, along with demonstrating the value and rigor of the agile SE process, NASA AFRC leadership ultimately permitted the ATDP project to solely use the agile SE process for developments beyond Phase I. While it is the opinion of the authors that the classical SE process is more effective for most projects at NASA AFRC, some projects may deem that the agile SE process is more advantageous. Although this paper is focused on introducing the agile SE process to NASA AFRC, lessons learned will be valuable to other organizations as well. Details of how the ATDP team implemented the agile SE process during Phase I will be summarized, along with how the team met all required classical SE milestones. Lessons learned throughout Phase I of this effort will also be highlighted.

Daniel S. Jones↗
DOE OSTI2020

Materials Data on Rh3Se8 by Materials Project

Rh3Se8 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Rh+3.33+ is bonded to six Se+1.25- atoms to form corner-sharing RhSe6 octahedra. The corner-sharing octahedra tilt angles range from 63–65°. There are a spread of Rh–Se bond distances ranging from 2.52–2.54 Å. There are two inequivalent Se+1.25- sites. In the first Se+1.25- site, Se+1.25- is bonded in a 3-coordinate geometry to two equivalent Rh+3.33+ and one Se+1.25- atom. The Se–Se bond length is 2.44 Å. In the second Se+1.25- site, Se+1.25- is bonded in a 4-coordinate geometry to three equivalent Rh+3.33+ and one Se+1.25- atom. The Se–Se bond length is 2.51 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaSe2 by Materials Project

NaSe2 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to six Se atoms to form distorted corner-sharing NaSe6 pentagonal pyramids. There are a spread of Na–Se bond distances ranging from 2.96–3.24 Å. In the second Na site, Na is bonded in a 6-coordinate geometry to six Se atoms. There are a spread of Na–Se bond distances ranging from 2.97–3.27 Å. There are two inequivalent Se sites. In the first Se site, Se is bonded in a distorted see-saw-like geometry to two Na and two Se atoms. There are one shorter (2.39 Å) and one longer (2.41 Å) Se–Se bond lengths. In the second Se site, Se is bonded in a 5-coordinate geometry to four Na and one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tl2B2Se7 by Materials Project

Tl2B2Se7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Tl1+ is bonded in a 6-coordinate geometry to nine Se+1.14- atoms. There are a spread of Tl–Se bond distances ranging from 3.34–3.93 Å. B3+ is bonded to four Se+1.14- atoms to form corner-sharing BSe4 tetrahedra. There are a spread of B–Se bond distances ranging from 2.05–2.08 Å. There are four inequivalent Se+1.14- sites. In the first Se+1.14- site, Se+1.14- is bonded in a distorted single-bond geometry to three equivalent Tl1+ and one B3+ atom. In the second Se+1.14- site, Se+1.14- is bonded in a distorted single-bond geometry to two equivalent Tl1+ and one B3+ atom. In the third Se+1.14- site, Se+1.14- is bonded in a distorted single-bond geometry to three equivalent Tl1+ and one B3+ atom. In the fourth Se+1.14- site, Se+1.14- is bonded in a water-like geometry to two equivalent Tl1+ and two equivalent B3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Rb2B2Se7 by Materials Project

Rb2B2Se7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Rb1+ is bonded in a 9-coordinate geometry to nine Se+1.14- atoms. There are a spread of Rb–Se bond distances ranging from 3.53–3.96 Å. B3+ is bonded to four Se+1.14- atoms to form corner-sharing BSe4 tetrahedra. There are a spread of B–Se bond distances ranging from 2.05–2.08 Å. There are four inequivalent Se+1.14- sites. In the first Se+1.14- site, Se+1.14- is bonded in a distorted single-bond geometry to three equivalent Rb1+ and one B3+ atom. In the second Se+1.14- site, Se+1.14- is bonded in a distorted single-bond geometry to two equivalent Rb1+ and one B3+ atom. In the third Se+1.14- site, Se+1.14- is bonded in a distorted single-bond geometry to three equivalent Rb1+ and one B3+ atom. In the fourth Se+1.14- site, Se+1.14- is bonded in a distorted water-like geometry to two equivalent Rb1+ and two equivalent B3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb2Se by Materials Project

Nb2Se crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one Nb2Se sheet oriented in the (0, 0, 1) direction. there are four inequivalent Nb sites. In the first Nb site, Nb is bonded in a 3-coordinate geometry to three Se atoms. There are two shorter (2.73 Å) and one longer (2.83 Å) Nb–Se bond lengths. In the second Nb site, Nb is bonded to five Se atoms to form distorted edge-sharing NbSe5 trigonal bipyramids. There are a spread of Nb–Se bond distances ranging from 2.65–2.72 Å. In the third Nb site, Nb is bonded in a 2-coordinate geometry to two Se atoms. There are one shorter (2.83 Å) and one longer (2.93 Å) Nb–Se bond lengths. In the fourth Nb site, Nb is bonded in a distorted L-shaped geometry to two equivalent Se atoms. Both Nb–Se bond lengths are 2.65 Å. There are two inequivalent Se sites. In the first Se site, Se is bonded in a distorted hexagonal planar geometry to six Nb atoms. In the second Se site, Se is bonded in a 6-coordinate geometry to six Nb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on V2Se9 by Materials Project

V2Se9 crystallizes in the monoclinic C2/c space group. The structure is one-dimensional and consists of two V2Se9 ribbons oriented in the (1, 0, 1) direction. V5+ is bonded in a 8-coordinate geometry to eight Se+1.11- atoms. There are a spread of V–Se bond distances ranging from 2.53–2.64 Å. There are five inequivalent Se+1.11- sites. In the first Se+1.11- site, Se+1.11- is bonded in a distorted single-bond geometry to one V5+ atom. In the second Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two equivalent V5+ atoms. In the third Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two equivalent V5+ atoms. In the fourth Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two equivalent V5+ atoms. In the fifth Se+1.11- site, Se+1.11- is bonded in a distorted L-shaped geometry to two equivalent V5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaPt2Se3 by Materials Project

NaPt2Se3 crystallizes in the hexagonal P6_3mc space group. The structure is two-dimensional and consists of two NaPt2Se3 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 3-coordinate geometry to three equivalent Se+1.67- atoms. All Na–Se bond lengths are 3.23 Å. In the second Na1+ site, Na1+ is bonded in a 3-coordinate geometry to three equivalent Se+1.67- atoms. All Na–Se bond lengths are 3.18 Å. There are two inequivalent Pt2+ sites. In the first Pt2+ site, Pt2+ is bonded in a square co-planar geometry to four Se+1.67- atoms. There are two shorter (2.47 Å) and two longer (2.48 Å) Pt–Se bond lengths. In the second Pt2+ site, Pt2+ is bonded in an octahedral geometry to six Se+1.67- atoms. There are three shorter (2.54 Å) and three longer (2.55 Å) Pt–Se bond lengths. There are two inequivalent Se+1.67- sites. In the first Se+1.67- site, Se+1.67- is bonded to one Na1+ and three Pt2+ atoms to form a mixture of distorted edge and corner-sharing SeNaPt3 trigonal pyramids. In the second Se+1.67- site, Se+1.67- is bonded to one Na1+ and three Pt2+ atoms to form a mixture of distorted edge and corner-sharing SeNaPt3 trigonal pyramids.

36 MATERIALS SCIENCE↗