Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Nb5Si3”

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.

3 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Nb5Si3 by Materials Project

Nb5Si3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Nb+2.40+ sites. In the first Nb+2.40+ site, Nb+2.40+ is bonded to six Si4- atoms to form NbSi6 octahedra that share corners with six equivalent NbSi6 octahedra, corners with sixteen equivalent NbSi5 trigonal bipyramids, and faces with eight equivalent NbSi5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–52°. There are four shorter (2.60 Å) and two longer (2.99 Å) Nb–Si bond lengths. In the second Nb+2.40+ site, Nb+2.40+ is bonded to five Si4- atoms to form NbSi5 trigonal bipyramids that share corners with four equivalent NbSi6 octahedra, corners with twelve equivalent NbSi5 trigonal bipyramids, edges with seven equivalent NbSi5 trigonal bipyramids, faces with two equivalent NbSi6 octahedra, and a faceface with one NbSi5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 43–64°. There are a spread of Nb–Si bond distances ranging from 2.61–2.74 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 10-coordinate geometry to ten Nb+2.40+ atoms. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to eight Nb+2.40+ and one Si4- atom. The Si–Si bond length is 2.41 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb5Si3 by Materials Project

Nb5Si3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Nb+2.40+ sites. In the first Nb+2.40+ site, Nb+2.40+ is bonded to five equivalent Si4- atoms to form distorted NbSi5 trigonal bipyramids that share corners with eight equivalent NbSi6 octahedra, corners with eight equivalent NbSi5 trigonal bipyramids, edges with six equivalent NbSi5 trigonal bipyramids, and faces with four equivalent NbSi6 octahedra. The corner-sharing octahedra tilt angles range from 41–55°. There are a spread of Nb–Si bond distances ranging from 2.61–2.86 Å. In the second Nb+2.40+ site, Nb+2.40+ is bonded to six equivalent Si4- atoms to form distorted NbSi6 octahedra that share corners with six equivalent NbSi6 octahedra, corners with twelve equivalent NbSi5 trigonal bipyramids, edges with three equivalent NbSi6 octahedra, faces with two equivalent NbSi6 octahedra, and faces with six equivalent NbSi5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 35°. All Nb–Si bond lengths are 2.69 Å. Si4- is bonded in a 9-coordinate geometry to nine Nb+2.40+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb5Si3 by Materials Project

Nb5Si3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Nb+2.40+ sites. In the first Nb+2.40+ site, Nb+2.40+ is bonded to six Si4- atoms to form distorted NbSi6 pentagonal pyramids that share corners with fifteen equivalent NbSi6 pentagonal pyramids, corners with four equivalent NbSi4 tetrahedra, edges with three equivalent NbSi6 pentagonal pyramids, edges with two equivalent NbSi4 tetrahedra, and faces with seven equivalent NbSi6 pentagonal pyramids. There are a spread of Nb–Si bond distances ranging from 2.66–2.95 Å. In the second Nb+2.40+ site, Nb+2.40+ is bonded to four equivalent Si4- atoms to form NbSi4 tetrahedra that share corners with sixteen equivalent NbSi6 pentagonal pyramids, edges with eight equivalent NbSi6 pentagonal pyramids, and edges with two equivalent NbSi4 tetrahedra. All Nb–Si bond lengths are 2.67 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 10-coordinate geometry to ten Nb+2.40+ atoms. In the second Si4- site, Si4- is bonded in a 10-coordinate geometry to eight equivalent Nb+2.40+ and two equivalent Si4- atoms. Both Si–Si bond lengths are 2.56 Å.

36 MATERIALS SCIENCE↗