Search NASA⌕ Search

SEARCH · Search NASA

Results for “O-Os-Pr”

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.

Materials Data on Pr3OsO7 by Materials Project

Pr3OsO7 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 (2.42 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 OsO6 octahedra, corners with three equivalent PrO7 pentagonal bipyramids, edges with two equivalent OsO6 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 2.33–2.61 Å. Os5+ is bonded to six O2- atoms to form OsO6 octahedra that share corners with two equivalent OsO6 octahedra, corners with four equivalent PrO7 pentagonal bipyramids, and edges with four equivalent PrO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 36°. There are four shorter (1.99 Å) and two longer (2.01 Å) Os–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 Os5+ 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 Os5+ atom.

36 MATERIALS SCIENCE↗