Search NASA⌕ Search

SEARCH · Search NASA

Results for “Ce-Ge-O”

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 Ce2(GeO3)3 by Materials Project

Ce2(GeO3)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Ce3+ sites. In the first Ce3+ site, Ce3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ce–O bond distances ranging from 2.28–2.84 Å. In the second Ce3+ site, Ce3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ce–O bond distances ranging from 2.32–2.95 Å. There are three inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to six O2- atoms to form GeO6 octahedra that share corners with two equivalent GeO4 tetrahedra, corners with two equivalent GeO5 trigonal bipyramids, and edges with two equivalent GeO6 octahedra. There are a spread of Ge–O bond distances ranging from 1.88–2.03 Å. In the second Ge4+ site, Ge4+ is bonded to five O2- atoms to form distorted GeO5 trigonal bipyramids that share corners with two equivalent GeO6 octahedra and an edgeedge with one GeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 45–56°. There are a spread of Ge–O bond distances ranging from 1.83–1.96 Å. In the third Ge4+ site, Ge4+ is bonded to four O2- atoms to form corner-sharing GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. There is two shorter (1.74 Å) and two longer (1.79 Å) Ge–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ce3+ and two equivalent Ge4+ atoms. In the second O2- site, O2- is bonded in a distorted L-shaped geometry to two Ce3+ and two equivalent Ge4+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ge4+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Ce3+ and two Ge4+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Ce3+ and one Ge4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Ce3+ and one Ge4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Ce3+ and two Ge4+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to three Ce3+ and one Ge4+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two Ce3+ and one Ge4+ atom.

36 MATERIALS SCIENCE↗