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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on La3NbO7 by Materials Project

La3NbO7 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 to seven O2- atoms to form distorted LaO7 pentagonal bipyramids that share corners with two equivalent NbO6 octahedra, corners with three equivalent LaO7 pentagonal bipyramids, edges with two equivalent NbO6 octahedra, and edges with two equivalent LaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 39°. There are a spread of La–O bond distances ranging from 2.34–2.77 Å. In the second La3+ site, La3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.45 Å) and four longer (2.78 Å) La–O bond lengths. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent LaO7 pentagonal bipyramids, and edges with four equivalent LaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 28°. All Nb–O bond lengths are 2.02 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent La3+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded to four La3+ atoms to form a mixture of edge and corner-sharing OLa4 tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three La3+ and one Nb5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaNb7O19 by Materials Project

LaNb7O19 crystallizes in the trigonal P321 space group. The structure is three-dimensional. La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.47–2.69 Å. There are four inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded in a distorted octahedral geometry to six O2- atoms. There are three shorter (1.96 Å) and three longer (2.09 Å) Nb–O bond lengths. In the second Nb5+ site, Nb5+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Nb–O bond distances ranging from 1.88–2.51 Å. In the third Nb5+ site, Nb5+ is bonded in a 7-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 2.00–2.05 Å. In the fourth Nb5+ site, Nb5+ is bonded in a 7-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.98–2.10 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to three equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a trigonal planar geometry to three equivalent Nb5+ atoms. In the sixth O2- site, O2- is bonded in a trigonal planar geometry to three equivalent Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one La3+ and three equivalent Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one La3+ and three equivalent Nb5+ atoms. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Nb5+ atoms. In the tenth O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaNbO4 by Materials Project

LaNbO4 is Zircon-like structured and crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. La3+ is bonded in a 8-coordinate geometry to eight equivalent O2- atoms. There are four shorter (2.52 Å) and four longer (2.53 Å) La–O bond lengths. Nb5+ is bonded in a tetrahedral geometry to four equivalent O2- atoms. All Nb–O bond lengths are 1.90 Å. O2- is bonded in a distorted trigonal planar geometry to two equivalent La3+ and one Nb5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaNbO4 by Materials Project

LaNbO4 is Zircon-like structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.50 Å) and four longer (2.54 Å) La–O bond lengths. Nb5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.88 Å) and two longer (1.92 Å) Nb–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent La3+ and one Nb5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent La3+ and one Nb5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaNb2O7 by Materials Project

LaNb2O7 crystallizes in the tetragonal P4/mmm space group. The structure is two-dimensional and consists of one LaNb2O7 sheet oriented in the (0, 0, 1) direction. La is bonded to twelve O atoms to form a mixture of face and corner-sharing LaO12 cuboctahedra. There are eight shorter (2.65 Å) and four longer (2.80 Å) La–O bond lengths. Nb is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Nb–O bond distances ranging from 1.76–2.27 Å. There are three inequivalent O sites. In the first O site, O is bonded to two equivalent La and two equivalent Nb atoms to form distorted OLa2Nb2 trigonal pyramids that share corners with four equivalent OLa4Nb2 octahedra, corners with ten equivalent OLa2Nb2 trigonal pyramids, edges with five equivalent OLa2Nb2 trigonal pyramids, and faces with two equivalent OLa4Nb2 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second O site, O is bonded in a single-bond geometry to one Nb atom. In the third O site, O is bonded to four equivalent La and two equivalent Nb atoms to form OLa4Nb2 octahedra that share corners with four equivalent OLa4Nb2 octahedra, corners with sixteen equivalent OLa2Nb2 trigonal pyramids, edges with four equivalent OLa4Nb2 octahedra, and faces with eight equivalent OLa2Nb2 trigonal pyramids. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗