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Materials Data on Pr3IrO7 by Materials Project

Pr3IrO7 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 in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.41 Å) and four longer (2.77 Å) Pr–O bond lengths. In the second Pr3+ site, Pr3+ is bonded to seven O2- atoms to form distorted PrO7 pentagonal bipyramids that share corners with two equivalent IrO6 octahedra, corners with three equivalent PrO7 pentagonal bipyramids, edges with two equivalent IrO6 octahedra, and edges with two equivalent PrO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 35°. There are a spread of Pr–O bond distances ranging from 2.33–2.59 Å. Ir5+ is bonded to six O2- atoms to form IrO6 octahedra that share corners with two equivalent IrO6 octahedra, corners with four equivalent PrO7 pentagonal bipyramids, and edges with four equivalent PrO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 38°. There are four shorter (1.99 Å) and two longer (2.02 Å) Ir–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Pr3+ and two equivalent Ir5+ atoms. In the second O2- site, O2- is bonded to four Pr3+ atoms to form a mixture of edge and corner-sharing OPr4 tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Pr3+ and one Ir5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Pr2Ir2O7 by Materials Project

Pr2Ir2O7 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Pr3+ is bonded to eight O2- atoms to form distorted PrO8 hexagonal bipyramids that share edges with six equivalent PrO8 hexagonal bipyramids and edges with six equivalent IrO6 octahedra. There are two shorter (2.28 Å) and six longer (2.57 Å) Pr–O bond lengths. Ir4+ is bonded to six equivalent O2- atoms to form IrO6 octahedra that share corners with six equivalent IrO6 octahedra and edges with six equivalent PrO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 49°. All Ir–O bond lengths are 2.04 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Pr3+ and two equivalent Ir4+ atoms to form a mixture of distorted edge and corner-sharing OPr2Ir2 tetrahedra. In the second O2- site, O2- is bonded to four equivalent Pr3+ atoms to form a mixture of edge and corner-sharing OPr4 tetrahedra.

36 MATERIALS SCIENCE↗