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Materials Data on PrNbO4 by Materials Project

PrNbO4 is Zircon-like structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Pr3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.48–2.51 Å. Nb5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.88 Å) and two longer (1.91 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 Pr3+ and one Nb5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Pr3+ and one Nb5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Pr3NbO7 by Materials Project

Pr3NbO7 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded to seven O2- atoms to form distorted PrO7 pentagonal bipyramids that share corners with two equivalent NbO6 octahedra, corners with three equivalent PrO7 pentagonal bipyramids, edges with two equivalent NbO6 octahedra, and edges with two equivalent PrO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 38°. There are a spread of Pr–O bond distances ranging from 2.33–2.71 Å. In the second Pr3+ site, Pr3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.44 Å) and four longer (2.77 Å) Pr–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 PrO7 pentagonal bipyramids, and edges with four equivalent PrO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 30°. 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 Pr3+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Pr3+ and one Nb5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on PrNb3O9 by Materials Project

PrNb3O9 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Pr3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.47–2.57 Å. There are three inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 32–52°. There are a spread of Nb–O bond distances ranging from 1.82–2.21 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 27–46°. There are a spread of Nb–O bond distances ranging from 1.86–2.26 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 27–52°. There are a spread of Nb–O bond distances ranging from 1.86–2.26 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Pr3+ and two Nb5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Pr3+ and two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Pr3+ and two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Pr3+ and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Pr3+ and two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Pr3+ and two Nb5+ atoms. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on PrNbO3 by Materials Project

PrNbO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pr3+ is bonded to twelve equivalent O2- atoms to form PrO12 cuboctahedra that share corners with twelve equivalent PrO12 cuboctahedra, faces with six equivalent PrO12 cuboctahedra, and faces with eight equivalent NbO6 octahedra. All Pr–O bond lengths are 2.89 Å. Nb3+ is bonded to six equivalent O2- atoms to form NbO6 octahedra that share corners with six equivalent NbO6 octahedra and faces with eight equivalent PrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Nb–O bond lengths are 2.04 Å. O2- is bonded in a distorted linear geometry to four equivalent Pr3+ and two equivalent Nb3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on PrNb4O12 by Materials Project

PrNb4O12 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Pr4+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Pr–O bond distances ranging from 2.51–2.84 Å. Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 6–28°. There are a spread of Nb–O bond distances ranging from 1.94–2.09 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted T-shaped geometry to one Pr4+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded in a linear geometry to one Pr4+ and two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Pr4+ and two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Pr4+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗