Search NASA⌕ Search

SEARCH · Search NASA

Results for “Al-Eu-O”

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

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

10 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on EuAlO3 by Materials Project

EuAlO3 is Orthorhombic Perovskite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Eu3+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of Eu–O bond distances ranging from 2.44–2.98 Å. Al3+ is bonded to six O2- atoms to form corner-sharing AlO6 octahedra. The corner-sharing octahedra tilt angles range from 14–16°. All Al–O bond lengths are 1.90 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four equivalent Eu3+ and two equivalent Al3+ atoms. In the second O2- site, O2- is bonded in a 5-coordinate geometry to four equivalent Eu3+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu4Al2O9 by Materials Project

Eu4Al2O9 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Eu3+ sites. In the first Eu3+ site, Eu3+ is bonded to six O2- atoms to form EuO6 octahedra that share corners with five AlO4 tetrahedra and edges with two equivalent EuO7 hexagonal pyramids. There are a spread of Eu–O bond distances ranging from 2.29–2.45 Å. In the second Eu3+ site, Eu3+ is bonded to seven O2- atoms to form distorted EuO7 hexagonal pyramids that share corners with three AlO4 tetrahedra, edges with two equivalent EuO6 octahedra, and edges with two AlO4 tetrahedra. There are a spread of Eu–O bond distances ranging from 2.33–2.61 Å. In the third Eu3+ site, Eu3+ is bonded in a 8-coordinate geometry to seven O2- atoms. There are a spread of Eu–O bond distances ranging from 2.34–2.74 Å. In the fourth Eu3+ site, Eu3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Eu–O bond distances ranging from 2.33–2.86 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one EuO7 hexagonal pyramid, corners with three equivalent EuO6 octahedra, a cornercorner with one AlO4 tetrahedra, and an edgeedge with one EuO7 hexagonal pyramid. The corner-sharing octahedra tilt angles range from 48–61°. There are a spread of Al–O bond distances ranging from 1.75–1.78 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two equivalent EuO7 hexagonal pyramids, corners with two equivalent EuO6 octahedra, a cornercorner with one AlO4 tetrahedra, and an edgeedge with one EuO7 hexagonal pyramid. The corner-sharing octahedra tilt angles range from 38–50°. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Eu3+ and one Al3+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Eu3+ and one Al3+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two Eu3+ and one Al3+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Eu3+ and two Al3+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Eu3+ and one Al3+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Eu3+ and one Al3+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to three Eu3+ and one Al3+ atom. In the eighth O2- site, O2- is bonded to four Eu3+ atoms to form a mixture of edge and corner-sharing OEu4 tetrahedra. In the ninth O2- site, O2- is bonded to four Eu3+ atoms to form a mixture of edge and corner-sharing OEu4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu2Al42O65 by Materials Project

Eu2Al42O65 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Eu sites. In the first Eu site, Eu is bonded in a distorted hexagonal planar geometry to six O atoms. There are a spread of Eu–O bond distances ranging from 2.39–2.82 Å. In the second Eu site, Eu is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Eu–O bond distances ranging from 2.33–2.94 Å. There are forty-two inequivalent Al sites. In the first Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with six AlO4 tetrahedra and edges with six AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.90–1.93 Å. In the second Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.08 Å. In the third Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.12 Å. In the fourth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.11 Å. In the fifth Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–61°. There are a spread of Al–O bond distances ranging from 1.81–1.84 Å. In the sixth Al site, Al is bonded in a trigonal non-coplanar geometry to three O atoms. There is two shorter (1.75 Å) and one longer (1.77 Å) Al–O bond length. In the seventh Al site, Al is bonded in a trigonal non-coplanar geometry to three O atoms. All Al–O bond lengths are 1.77 Å. In the eighth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.84–2.03 Å. In the ninth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.06 Å. In the tenth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.08 Å. In the eleventh Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–59°. There is one shorter (1.79 Å) and three longer (1.84 Å) Al–O bond length. In the twelfth Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–65°. There are a spread of Al–O bond distances ranging from 1.78–1.91 Å. In the thirteenth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with six AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.87–2.01 Å. In the fourteenth Al site, Al is bonded to six O atoms to form distorted AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.75–2.16 Å. In the fifteenth Al site, Al is bonded to six O atoms to form distorted AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.75–2.16 Å. In the sixteenth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.83–2.11 Å. In the seventeenth Al site, Al is bonded in a trigonal planar geometry to three O atoms. There are a spread of Al–O bond distances ranging from 1.69–1.73 Å. In the eighteenth Al site, Al is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Al–O bond distances ranging from 1.74–2.31 Å. In the nineteenth Al site, Al is bonded to six O atoms to form distorted AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.74–2.16 Å. In the twentieth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.79–2.07 Å. In the twenty-first Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Al–O bond distances ranging from 1.77–1.86 Å. In the twenty-second Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–62°. There are a spread of Al–O bond distances ranging from 1.76–1.85 Å. In the twenty-third Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with six AlO4 tetrahedra and edges with six AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.90–2.01 Å. In the twenty-fourth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.78–2.12 Å. In the twenty-fifth Al site, Al is bonded to six O atoms to form distorted AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.73–2.19 Å. In the twenty-sixth Al site, Al is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Al–O bond distances ranging from 1.76–2.41 Å. In the twenty-seventh Al site, Al is bonded in a trigonal planar geometry to three O atoms. There are a spread of Al–O bond distances ranging from 1.70–1.72 Å. In the twenty-eighth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.83–2.05 Å. In the twenty-ninth Al site, Al is bonded to six O atoms to form distorted AlO6 octahedra that share corners with four AlO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.79–2.19 Å. In the thirtieth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four AlO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–1.98 Å. In the thirty-first Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–65°. There are a spread of Al–O bond distances ranging from 1.80–1.92 Å. In the thirty-second Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–63°. There are a spread of Al–O bond distances ranging from 1.79–1.86 Å. In the thirty-third Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with six AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.88–2.02 Å. In the thirty-fourth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.83–2.02 Å. In the thirty-fifth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.06 Å. In the thirty-sixth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.85–2.00 Å. In the thirty-seventh Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with six AlO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–58°. There are a spread of Al–O bond distances ranging from 1.71–1.81 Å. In the thirty-eighth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with six AlO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–57°. There are a spread of Al–O bond distances ranging from 1.71–1.80 Å. In the thirty-ninth Al site, Al is bonded to four O atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–61°. There is three shorter (1.82 Å) and one longer (1.84 Å) Al–O bond length. In the fortieth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.81–2.07 Å. In the forty-first Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.81–2.06 Å. In the forty-second Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.09 Å. There are sixty-five inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to three Al atoms. In the second O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the third O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the fourth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the fifth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the sixth O site, O is bonded in a trigonal non-coplanar geometry to three Al atoms. In the seventh O site, O is bonded in a trigonal planar geometry to three Al atoms. In the eighth O site, O is bonded in a trigonal planar geometry to three Al atoms. In the ninth O site, O is bonded in a trigonal planar geometry to three Al atoms. In the tenth O site, O is bonded in a trigonal planar geometry to three Al atoms. In the eleventh O site, O is bonded in a trigonal planar geometry to three Al atoms. In the twelfth O site, O is bonded in a trigonal planar geometry to three Al atoms. In the thirteenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the fourteenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the fifteenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the sixteenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the seventeenth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the eighteenth O site, O is bonded in a 4-coordinate geometry to four Al atoms. In the nineteenth O site, O is bonded in a distorted rectangular see-saw-like geometry to four Al atoms. In the twentieth O site, O is bonded in a rectangular see-saw-like geometry to four Al atoms. In the twenty-first O site, O is bonded in a distorted trigonal non-coplanar geometry to one Eu and three Al atoms. In the twenty-second O site, O is bonded in a water-like geometry to two Al atoms. In the twenty-third O site, O is bonded in a water-like geometry to two Al atoms. In the twenty-fourth O site, O is bonded in a 3-coordinate geometry to one Eu and two Al atoms. In the twenty-fifth O site, O is bonded in a 4

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu2Al4O9 by Materials Project

Eu2Al4O9 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Eu3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Eu–O bond distances ranging from 2.25–2.54 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with four equivalent AlO4 tetrahedra and edges with two equivalent AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.90–1.98 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four equivalent AlO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–56°. There is one shorter (1.73 Å) and three longer (1.78 Å) Al–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent Al3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Eu3+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to three Al3+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Eu3+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu2Al2O5 by Materials Project

Eu2Al2O5 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Eu2+ sites. In the first Eu2+ site, Eu2+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Eu–O bond lengths are 2.55 Å. In the second Eu2+ site, Eu2+ is bonded to twelve O2- atoms to form EuO12 cuboctahedra that share corners with four equivalent EuO12 cuboctahedra, faces with four equivalent EuO12 cuboctahedra, and faces with eight equivalent AlO5 square pyramids. There are four shorter (2.67 Å) and eight longer (2.81 Å) Eu–O bond lengths. Al3+ is bonded to five O2- atoms to form AlO5 square pyramids that share corners with five equivalent AlO5 square pyramids and faces with four equivalent EuO12 cuboctahedra. There is one shorter (1.82 Å) and four longer (1.91 Å) Al–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to four Eu2+ and two equivalent Al3+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent Eu2+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on EuAlO3 by Materials Project

EuAlO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Eu3+ is bonded to twelve equivalent O2- atoms to form EuO12 cuboctahedra that share corners with twelve equivalent EuO12 cuboctahedra, faces with six equivalent EuO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. All Eu–O bond lengths are 2.66 Å. Al3+ is bonded to six equivalent O2- atoms to form AlO6 octahedra that share corners with six equivalent AlO6 octahedra and faces with eight equivalent EuO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Al–O bond lengths are 1.88 Å. O2- is bonded in a distorted linear geometry to four equivalent Eu3+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on EuAl2O4 by Materials Project

EuAl2O4 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Eu2+ sites. In the first Eu2+ site, Eu2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Eu–O bond distances ranging from 2.54–3.13 Å. In the second Eu2+ site, Eu2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Eu–O bond distances ranging from 2.49–2.83 Å. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There is two shorter (1.77 Å) and two longer (1.79 Å) Al–O bond length. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There is two shorter (1.77 Å) and two longer (1.78 Å) Al–O bond length. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There is two shorter (1.77 Å) and two longer (1.78 Å) Al–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Eu2+ and two Al3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Eu2+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Eu2+ and two Al3+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Eu2+ and two Al3+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Eu2+ and two Al3+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Eu2+ and two Al3+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Eu2+ and two Al3+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Eu2+ and two Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu3AlO5 by Materials Project

Eu3AlO5 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Eu+2.33+ sites. In the first Eu+2.33+ site, Eu+2.33+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Eu–O bond distances ranging from 2.36–2.73 Å. In the second Eu+2.33+ site, Eu+2.33+ is bonded in a distorted q6 geometry to ten O2- atoms. There are two shorter (2.78 Å) and eight longer (2.81 Å) Eu–O bond lengths. Al3+ is bonded in a tetrahedral geometry to four equivalent O2- atoms. All Al–O bond lengths are 1.76 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to six Eu+2.33+ atoms to form corner-sharing OEu6 octahedra. The corner-sharing octahedra tilt angles range from 0–32°. In the second O2- site, O2- is bonded in a 6-coordinate geometry to five Eu+2.33+ and one Al3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu2Al3O8 by Materials Project

Eu2Al3O8 crystallizes in the cubic I-43m space group. The structure is three-dimensional. Eu is bonded to six O atoms to form EuO6 octahedra that share corners with six equivalent AlO4 tetrahedra and edges with three equivalent EuO6 octahedra. There are three shorter (2.34 Å) and three longer (2.40 Å) Eu–O bond lengths. Al is bonded to four equivalent O atoms to form AlO4 tetrahedra that share corners with four equivalent EuO6 octahedra and corners with four equivalent AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 64°. All Al–O bond lengths are 1.77 Å. There are two inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to three equivalent Eu atoms. In the second O site, O is bonded in a trigonal planar geometry to one Eu and two equivalent Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu3Al2O7 by Materials Project

Eu3Al2O7 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Eu+2.67+ sites. In the first Eu+2.67+ site, Eu+2.67+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Eu–O bond distances ranging from 2.37–2.67 Å. In the second Eu+2.67+ site, Eu+2.67+ is bonded to twelve O2- atoms to form EuO12 cuboctahedra that share corners with four equivalent EuO12 cuboctahedra, faces with four equivalent EuO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. There are four shorter (2.66 Å) and eight longer (2.69 Å) Eu–O bond lengths. Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with five equivalent AlO6 octahedra and faces with four equivalent EuO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Al–O bond distances ranging from 1.88–2.03 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four Eu+2.67+ and two equivalent Al3+ atoms. In the second O2- site, O2- is bonded to five equivalent Eu+2.67+ and one Al3+ atom to form a mixture of distorted edge and corner-sharing OEu5Al octahedra. The corner-sharing octahedral tilt angles are 13°. In the third O2- site, O2- is bonded in a distorted linear geometry to four equivalent Eu+2.67+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗