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DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. La3+ is bonded to twelve equivalent O2- atoms to form distorted LaO12 cuboctahedra that share corners with twelve equivalent LaO12 cuboctahedra, faces with six equivalent LaO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. There are a spread of La–O bond distances ranging from 2.49–2.92 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 LaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 13°. All Al–O bond lengths are 1.92 Å. O2- is bonded in a 2-coordinate geometry to four equivalent La3+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. La3+ is bonded to twelve equivalent O2- atoms to form LaO12 cuboctahedra that share corners with twelve equivalent LaO12 cuboctahedra, faces with six equivalent LaO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. All La–O bond lengths are 2.69 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 LaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Al–O bond lengths are 1.91 Å. O2- is bonded in a distorted linear geometry to four equivalent La3+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.33–3.05 Å. In the second La3+ site, La3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of La–O bond distances ranging from 2.28–2.63 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to five O2- atoms to form AlO5 trigonal bipyramids that share a cornercorner with one AlO6 octahedra, corners with two equivalent AlO5 trigonal bipyramids, and edges with two equivalent AlO6 octahedra. The corner-sharing octahedral tilt angles are 34°. There are a spread of Al–O bond distances ranging from 1.78–1.90 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra, a cornercorner with one AlO5 trigonal bipyramid, and edges with two equivalent AlO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 9°. There are a spread of Al–O bond distances ranging from 1.90–2.01 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to three La3+ and one Al3+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to four La3+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a distorted see-saw-like geometry to one La3+ and three Al3+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two La3+ and three Al3+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the sixth O2- site, O2- is bonded to three La3+ and one Al3+ atom to form distorted corner-sharing OLa3Al tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to seven O2- atoms to form distorted LaO7 pentagonal bipyramids that share corners with four AlO4 tetrahedra, edges with two equivalent LaO6 octahedra, edges with two equivalent LaO7 pentagonal bipyramids, and edges with two AlO4 tetrahedra. There are a spread of La–O bond distances ranging from 2.38–2.62 Å. In the second La3+ site, La3+ is bonded to six O2- atoms to form distorted LaO6 octahedra that share corners with five AlO4 tetrahedra, edges with two equivalent LaO7 pentagonal bipyramids, and an edgeedge with one AlO4 tetrahedra. There are a spread of La–O bond distances ranging from 2.34–2.63 Å. In the third La3+ site, La3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of La–O bond distances ranging from 2.42–2.66 Å. There are three 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 LaO6 octahedra, corners with two equivalent LaO7 pentagonal bipyramids, corners with two AlO4 tetrahedra, and an edgeedge with one LaO6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of Al–O bond distances ranging from 1.78–1.80 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with three equivalent LaO6 octahedra, a cornercorner with one LaO7 pentagonal bipyramid, corners with two AlO4 tetrahedra, and an edgeedge with one LaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 45–59°. There are a spread of Al–O bond distances ranging from 1.75–1.79 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one LaO6 octahedra, a cornercorner with one LaO7 pentagonal bipyramid, corners with two AlO4 tetrahedra, and an edgeedge with one LaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 45°. There are a spread of Al–O bond distances ranging from 1.76–1.79 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Al3+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one La3+ and two Al3+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one La3+ and two Al3+ atoms. In the seventh O2- site, O2- is bonded to three La3+ and one Al3+ atom to form distorted edge-sharing OLa3Al tetrahedra. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two La3+ and one Al3+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two La3+ and one Al3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.38–2.68 Å. In the second La3+ site, La3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.41–2.65 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There is two shorter (1.75 Å) and two longer (1.79 Å) Al–O bond length. 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. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and two equivalent Al3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and two Al3+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.42–3.06 Å. In the second La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.34–3.10 Å. There are two 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 1.74–1.79 Å. In the second 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 1.76–1.80 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three La3+ and two Al3+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Al3+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to three La3+ and one Al3+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one La3+ and two Al3+ atoms. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Al3+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Al3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.47–2.72 Å. In the second La3+ site, La3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of La–O bond distances ranging from 2.30–2.69 Å. In the third La3+ site, La3+ is bonded to six O2- atoms to form distorted LaO6 octahedra that share corners with six AlO4 tetrahedra and an edgeedge with one LaO6 octahedra. There are a spread of La–O bond distances ranging from 2.39–2.55 Å. There are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two equivalent LaO6 octahedra and corners with two AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 63–72°. There are a spread of Al–O bond distances ranging from 1.76–1.79 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one LaO6 octahedra and corners with two AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Al–O bond distances ranging from 1.77–1.80 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with three equivalent LaO6 octahedra and corners with two AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–72°. There are a spread of Al–O bond distances ranging from 1.76–1.80 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the fifth O2- site, O2- is bonded to three La3+ and one Al3+ atom to form a mixture of distorted edge and corner-sharing OLa3Al tetrahedra. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one La3+ and two Al3+ atoms. In the seventh O2- site, O2- is bonded to three La3+ and one Al3+ atom to form a mixture of distorted edge and corner-sharing OLa3Al tetrahedra. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to two Al3+ atoms. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one La3+ and two Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.42–3.01 Å. In the second La3+ site, La3+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.39–3.08 Å. In the third La3+ site, La3+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.40–2.96 Å. There are three 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 1.79–1.82 Å. In the second 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 1.78–1.81 Å. In the third 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 1.75–1.78 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Al3+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to four La3+ and one Al3+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two La3+ and two Al3+ atoms. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three La3+ and one Al3+ atom. In the fifth O2- site, O2- is bonded to three La3+ and one Al3+ atom to form distorted edge-sharing OLa3Al tetrahedra. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Al3+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Al3+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.42–2.76 Å. In the second La3+ site, La3+ is bonded in a 6-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.42–2.98 Å. In the third La3+ site, La3+ is bonded to seven O2- atoms to form distorted LaO7 hexagonal pyramids that share corners with four AlO4 tetrahedra, an edgeedge with one LaO7 hexagonal pyramid, and edges with two AlO4 tetrahedra. There are a spread of La–O bond distances ranging from 2.36–2.67 Å. In the fourth La3+ site, La3+ is bonded to seven O2- atoms to form distorted LaO7 hexagonal pyramids that share corners with four AlO4 tetrahedra, an edgeedge with one LaO7 hexagonal pyramid, and edges with two AlO4 tetrahedra. There are a spread of La–O bond distances ranging from 2.37–2.67 Å. In the fifth La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.41–2.97 Å. In the sixth La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.41–2.79 Å. There are six 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 LaO7 hexagonal pyramid, corners with two AlO4 tetrahedra, and an edgeedge with one LaO7 hexagonal pyramid. There are a spread of Al–O bond distances ranging from 1.74–1.81 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one LaO7 hexagonal pyramid and corners with two AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.80 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two LaO7 hexagonal pyramids, corners with two AlO4 tetrahedra, and an edgeedge with one LaO7 hexagonal pyramid. There are a spread of Al–O bond distances ranging from 1.74–1.81 Å. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two LaO7 hexagonal pyramids, corners with two AlO4 tetrahedra, and an edgeedge with one LaO7 hexagonal pyramid. There are a spread of Al–O bond distances ranging from 1.74–1.81 Å. In the fifth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one LaO7 hexagonal pyramid, corners with two AlO4 tetrahedra, and an edgeedge with one LaO7 hexagonal pyramid. There are a spread of Al–O bond distances ranging from 1.74–1.81 Å. In the sixth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one LaO7 hexagonal pyramid and corners with two AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.80 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Al3+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two La3+ and one Al3+ atom. In the fifth O2- site, O2- is bonded to three La3+ and one Al3+ atom to form a mixture of distorted edge and corner-sharing OLa3Al tetrahedra. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two La3+ and two Al3+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Al3+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Al3+ atoms. In the ninth O2- site, O2- is bonded to three La3+ and one Al3+ atom to form a mixture of distorted edge and corner-sharing OLa3Al tetrahedra. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Al3+ atoms. In the eleventh O2- site, O2- is bonded to three La3+ and one Al3+ atom to form a mixture of distorted edge and corner-sharing OLa3Al tetrahedra. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Al3+ atom. In the thirteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two La3+ and two Al3+ atoms. In the fourteenth O2- site, O2- is bonded to three La3+ and one Al3+ atom to form a mixture of distorted edge and corner-sharing OLa3Al tetrahedra. In the fifteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two La3+ and one Al3+ atom. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Al3+ atoms. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Al3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to six O2- atoms to form distorted LaO6 octahedra that share corners with five AlO4 tetrahedra, edges with two equivalent LaO6 octahedra, edges with two equivalent LaO7 pentagonal bipyramids, and an edgeedge with one AlO4 tetrahedra. There are a spread of La–O bond distances ranging from 2.36–2.66 Å. In the second La3+ site, La3+ is bonded to six O2- atoms to form distorted LaO6 octahedra that share corners with five AlO4 tetrahedra, edges with two equivalent LaO6 octahedra, edges with two equivalent LaO7 pentagonal bipyramids, and an edgeedge with one AlO4 tetrahedra. There are a spread of La–O bond distances ranging from 2.42–2.65 Å. In the third La3+ site, La3+ is bonded to seven O2- atoms to form distorted LaO7 pentagonal bipyramids that share corners with four AlO4 tetrahedra, edges with four LaO6 octahedra, edges with two equivalent LaO7 pentagonal bipyramids, and edges with two AlO4 tetrahedra. There are a spread of La–O bond distances ranging from 2.39–2.58 Å. There are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four LaO6 octahedra, a cornercorner with one LaO7 pentagonal bipyramid, corners with two AlO4 tetrahedra, and an edgeedge with one LaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 47–67°. There are a spread of Al–O bond distances ranging from 1.76–1.80 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four LaO6 octahedra, a cornercorner with one LaO7 pentagonal bipyramid, corners with two AlO4 tetrahedra, and an edgeedge with one LaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 47–67°. There are a spread of Al–O bond distances ranging from 1.76–1.80 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two LaO6 octahedra, corners with two equivalent LaO7 pentagonal bipyramids, corners with two AlO4 tetrahedra, and edges with two LaO6 octahedra. The corner-sharing octahedra tilt angles range from 56–57°. There are a spread of Al–O bond distances ranging from 1.78–1.80 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two La3+ and one Al3+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two La3+ and one Al3+ atom. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to one La3+ and two Al3+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one La3+ and two Al3+ atoms. In the seventh O2- site, O2- is bonded to three La3+ and one Al3+ atom to form distorted corner-sharing OLa3Al tetrahedra. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Al3+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Al3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. La3+ is bonded to twelve O2- atoms to form distorted LaO12 cuboctahedra that share corners with twelve equivalent LaO12 cuboctahedra, faces with six equivalent LaO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. There are a spread of La–O bond distances ranging from 2.50–2.92 Å. Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six equivalent AlO6 octahedra and faces with eight equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 9–13°. All Al–O bond lengths are 1.92 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four equivalent La3+ and two equivalent Al3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to four equivalent La3+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaAlO3 by Materials Project

LaAlO3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with twelve equivalent LaO12 cuboctahedra, faces with six equivalent LaO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. There are a spread of La–O bond distances ranging from 2.55–2.86 Å. Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six equivalent AlO6 octahedra and faces with eight equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–13°. All Al–O bond lengths are 1.92 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four equivalent La3+ and two equivalent Al3+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent La3+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Soft x-ray absorption spectroscopy and magnetic circular dichroism as operando probes of complex oxide electrolyte gate transistors

Electrolyte-based transistors utilizing ionic liquids/gels have been highly successful in the study of charge-density-controlled phenomena, particularly in oxides. Experimental probes beyond transport have played a significant role, despite challenges in their application in electric double-layer transistors. Here, we demonstrate the application of synchrotron soft x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) as operando probes of the charge state and magnetism in ion-gel-gated ferromagnetic perovskite films. Electrochemical response via oxygen vacancies at positive gate bias in LaAlO 3 (001)/La 0.5 Sr 0.5 CoO 3-δ is used as a test case. XAS/XMCD measurements of 4–25 unit-cell-thick films first probe the evolution of hole doping (from the O K-edge pre-peak) and ferromagnetism (at the Co L-edges), to establish a baseline. Operando soft XAS/XMCD of electrolyte-gated films is then demonstrated, using optimized spin-coated gels with a thickness of ~1 μm and a specific composition. The application of gate voltages up to +4 V is shown to dramatically suppress the O K-edge XAS pre-peak intensity and Co L-edge XMCD, thus enabling the Co valence and ferromagnetism to be tracked upon gate-induced reduction. Soft XAS and XMCD, with appropriate electrolyte design, are thus established to be viable for the operando characterization of electrolyte-gated oxides.

Yu, Biqiong↗
DOE OSTI2020

Molecular beam epitaxy of the magnetic Kagome metal FeSn on LaAlO 3 (111)

Materials with Kagome layers are expected to give rise to rich physics arising from band structures with topological properties, spin liquid behavior, and the formation of Skyrmions. Until now, most work on Kagome materials has been performed on bulk samples due to difficulties in thin film synthesis. Here, by using molecular beam epitaxy, layered Kagome-structured FeSn films are synthesized on the (111) oriented LaAlO3 substrate. Both in situ and ex situ characterizations indicate that these films are highly crystalline and c-axis oriented, with atomically smooth surfaces. The films grow as disconnected islands, with lateral dimensions on the micron meter scale. By patterning Pt electrodes using a focused electron beam, the longitudinal and transverse resistance of single islands have been measured in magnetic fields. Our work opens a pathway for exploring mesoscale transport properties in thin films of Kagome materials and related devices.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Growth and characterization of La 0.67 Sr 0.33 MnO 3 /YBa 2 Cu 3 O 7- δ bilayers

Understanding the interplay of ferromagnets and superconductors requires high quality interfaces. To this end, we have fabricated heterostructures of the cuprate superconductor YBa2Cu3O7-δ (YBCO) with the metallic ferromagnet La0.67Sr0.33MnO3 (LSMO) via pulsed laser deposition on SrTiO3 (STO) (001) and (LaAlO3)0.3(Sr2TaAlO6)0.7 (LSAT) (001) substrates. By varying the YBCO thickness from 1.7-13.6 nm while keeping the LSMO thickness at 12 nm, we have studied the interplay between ferromagnetism and superconductivity in the in-plane transport and magnetic properties of the bilayers. X-ray reflectivity data indicate the presence of a 2-3 nm thick interfacial layer between the LSMO and YBCO layers in all heterostructures. In-plane transport measurements exhibit suppression of the superconducting transition temperature from bulk YBCO values. Magnetometry measurements indicate high LSMO saturation magnetization values for samples grown on STO substrates and even higher (bulk-like) magnetization for bilayers grown on LSAT substrates. Together these results indicate that the interdiffused layer is largely attributed to a modified YBCO layer.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Two-dimensional electron systems in perovskite oxide heterostructures: Role of the polarity-induced substitutional defects

The discovery of a two-dimensional electron system (2DES) at the interfaces of perovskite oxides such as LaAlO 3 and SrTiO 3 has motivated enormous efforts in engineering interfacial functionalities with this type of oxide heterostructures. However, the fundamental origins of the 2DES are still not understood, e.g., the microscopic mechanisms of coexisting interface conductivity and magnetism. In this paper, we report a comprehensive spectroscopic investigation on the depth profile of 2DES-relevant Ti 3d interface carriers using depth- and element-specific techniques like standing-wave excited photoemission and resonant inelastic scattering. We found that one type of Ti 3d interface carriers, which give rise to the 2DES are located within three unit cells from the n-type interface in the SrTiO 3 layer. Unexpectedly, another type of interface carriers, which are polarity-induced Ti-on-Al antisite defects, reside in the first three unit cells of the opposing LaAlO3 layer (~10 Å). Our findings provide a microscopic picture of how the localized and mobile Ti 3d interface carriers distribute across the interface and suggest that the 2DES and 2D magnetism at the LaAlO 3 /SrTiO 3 interface have disparate explanations as originating from different types of interface carriers.

36 MATERIALS SCIENCE↗
DOE OSTI2021

In situ investigation of conducting interface formation in $\mathrm{LaAlO_3}$/$\mathrm{SrTiO_3}$ heterostructure

The high-mobility conducting interface (CI) between LaAlO 3 (LAO) and SrTiO 3 (STO) has revealed many fascinating phenomena, including exotic magnetism and superconductivity. But, the formation mechanism of the CI has not been conclusively explained. Here, using in situ angle-resolved photoemission spectroscopy, we elucidated the mechanisms for the CI formation. In as-grown samples, we observed a built-in potential (V bi ) proportional to the polar LAO thickness starting from the first unit cell (UC) with CI formation appearing above 3 UCs. However, we found that the V bi is removed by synchrotron ultraviolet (UV)-irradiation; The built-in potential is recovered by oxygen gas (O 2 (g))-exposure. Furthermore, after UV-irradiation, the CI appears even below 3UC of LAO. Here, our results demonstrate not only the V bi -driven CI formation in as-grown LAO/STO, but also a new route to control of the interface state by UV lithographic patterning or other surface modification.

36 MATERIALS SCIENCE↗