Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “F-Nb-O-Pb”

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 Nb3Pb2O7F5 by Materials Project

Pb2Nb3O7F5 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. there are three inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to five O2- and one F1- atom to form distorted NbO5F octahedra that share corners with five NbO5F octahedra and faces with four equivalent PbO4F8 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–25°. There are a spread of Nb–O bond distances ranging from 1.86–2.02 Å. The Nb–F bond length is 2.29 Å. In the second Nb5+ site, Nb5+ is bonded to three O2- and three F1- atoms to form distorted corner-sharing NbO3F3 octahedra. The corner-sharing octahedra tilt angles range from 0–23°. There is one shorter (1.77 Å) and two longer (1.97 Å) Nb–O bond length. There are two shorter (2.02 Å) and one longer (2.26 Å) Nb–F bond lengths. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 0–16°. There are a spread of Nb–O bond distances ranging from 1.96–2.26 Å. There are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 4-coordinate geometry to eight F1- atoms. There are a spread of Pb–F bond distances ranging from 2.39–2.92 Å. In the second Pb2+ site, Pb2+ is bonded to four O2- and eight F1- atoms to form PbO4F8 cuboctahedra that share corners with four equivalent PbO4F8 cuboctahedra, faces with four equivalent PbO4F8 cuboctahedra, and faces with four equivalent NbO5F octahedra. All Pb–O bond lengths are 2.89 Å. There are a spread of Pb–F bond distances ranging from 2.65–2.78 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two Nb5+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to two Nb5+ atoms. In the third O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. In the fourth O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Nb5+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Nb5+ and two equivalent Pb2+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Nb5+ and two equivalent Pb2+ atoms. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a 1-coordinate geometry to one Nb5+ and four equivalent Pb2+ atoms. In the second F1- site, F1- is bonded in a distorted single-bond geometry to one Nb5+ and four equivalent Pb2+ atoms. In the third F1- site, F1- is bonded to four Pb2+ atoms to form a mixture of distorted edge and corner-sharing FPb4 tetrahedra. In the fourth F1- site, F1- is bonded to four Pb2+ atoms to form a mixture of distorted edge and corner-sharing FPb4 tetrahedra. In the fifth F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb4Pb3(O6F)2 by Materials Project

Nb4Pb3(O6F)2 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are seven 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 40–55°. There are a spread of Nb–O bond distances ranging from 1.84–2.20 Å. In the second Nb5+ site, Nb5+ is bonded to five O2- and one F1- atom to form corner-sharing NbO5F octahedra. The corner-sharing octahedra tilt angles range from 33–46°. There are a spread of Nb–O bond distances ranging from 1.95–2.05 Å. The Nb–F bond length is 2.04 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 36–51°. There are a spread of Nb–O bond distances ranging from 1.81–2.33 Å. In the fourth Nb5+ site, Nb5+ is bonded to five O2- and one F1- atom to form corner-sharing NbO5F octahedra. The corner-sharing octahedra tilt angles range from 34–51°. There are a spread of Nb–O bond distances ranging from 1.92–2.10 Å. The Nb–F bond length is 2.10 Å. In the fifth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 29–49°. There are a spread of Nb–O bond distances ranging from 1.93–2.12 Å. In the sixth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 29–49°. There are a spread of Nb–O bond distances ranging from 1.94–2.10 Å. In the seventh Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 29–49°. There are a spread of Nb–O bond distances ranging from 1.94–2.09 Å. There are six inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 8-coordinate geometry to six O2- and two equivalent F1- atoms. There are a spread of Pb–O bond distances ranging from 2.65–2.79 Å. Both Pb–F bond lengths are 2.53 Å. In the second Pb2+ site, Pb2+ is bonded in a 8-coordinate geometry to six O2- and two F1- atoms. There are a spread of Pb–O bond distances ranging from 2.46–2.90 Å. There are one shorter (2.49 Å) and one longer (2.70 Å) Pb–F bond lengths. In the third Pb2+ site, Pb2+ is bonded in a 7-coordinate geometry to five O2- and two F1- atoms. There are a spread of Pb–O bond distances ranging from 2.52–2.96 Å. There are one shorter (2.50 Å) and one longer (2.53 Å) Pb–F bond lengths. In the fourth Pb2+ site, Pb2+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Pb–O bond distances ranging from 2.28–3.04 Å. The Pb–F bond length is 2.84 Å. In the fifth Pb2+ site, Pb2+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Pb–O bond distances ranging from 2.43–2.97 Å. The Pb–F bond length is 2.57 Å. In the sixth Pb2+ site, Pb2+ is bonded in a 7-coordinate geometry to five O2- and two F1- atoms. There are a spread of Pb–O bond distances ranging from 2.52–3.00 Å. There are one shorter (2.36 Å) and one longer (2.65 Å) Pb–F bond lengths. There are nineteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two Nb5+ and two Pb2+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Nb5+ and two Pb2+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Nb5+ and two Pb2+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Nb5+ and two Pb2+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two Nb5+ and one Pb2+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Nb5+ and one Pb2+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two Nb5+ and one Pb2+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Nb5+ and one Pb2+ atom. In the ninth O2- site, O2- is bonded to two equivalent Nb5+ and two equivalent Pb2+ atoms to form distorted ONb2Pb2 tetrahedra that share corners with four FPb4 tetrahedra. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Nb5+ and two equivalent Pb2+ atoms. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to two Nb5+ and two equivalent Pb2+ atoms. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Nb5+ atoms. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Nb5+ atoms. In the fourteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Nb5+ and two Pb2+ atoms. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Nb5+ and two equivalent Pb2+ atoms. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Nb5+ and two equivalent Pb2+ atoms. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to one Nb5+ and one Pb2+ atom. In the nineteenth O2- site, O2- is bonded in a distorted single-bond geometry to one Nb5+ and one Pb2+ atom. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded to four Pb2+ atoms to form distorted edge-sharing FPb4 tetrahedra. In the second F1- site, F1- is bonded to four Pb2+ atoms to form distorted FPb4 tetrahedra that share corners with two equivalent ONb2Pb2 tetrahedra and an edgeedge with one FPb4 tetrahedra. In the third F1- site, F1- is bonded to four Pb2+ atoms to form distorted FPb4 tetrahedra that share corners with two equivalent ONb2Pb2 tetrahedra and an edgeedge with one FPb4 tetrahedra. In the fourth F1- site, F1- is bonded in a 1-coordinate geometry to one Nb5+ and one Pb2+ atom. In the fifth F1- site, F1- is bonded in a 2-coordinate geometry to one Nb5+ and one Pb2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb3Pb2(O2F)4 by Materials Project

Nb3Pb2(O2F)4 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Nb+4.67+ sites. In the first Nb+4.67+ site, Nb+4.67+ is bonded to five O2- and one F1- atom to form distorted corner-sharing NbO5F octahedra. The corner-sharing octahedra tilt angles range from 0–21°. There is one shorter (1.86 Å) and four longer (2.00 Å) Nb–O bond length. The Nb–F bond length is 2.26 Å. In the second Nb+4.67+ site, Nb+4.67+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.97 Å) and two longer (2.04 Å) Nb–O bond lengths. Pb3+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are four shorter (2.52 Å) and four longer (2.84 Å) Pb–F bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Nb+4.67+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two equivalent Nb+4.67+ atoms. In the third O2- site, O2- is bonded in a linear geometry to two Nb+4.67+ atoms. In the fourth O2- site, O2- is bonded in a linear geometry to two equivalent Nb+4.67+ atoms. Both O–Nb bond lengths are 1.97 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to one Nb+4.67+ and four equivalent Pb3+ atoms. In the second F1- site, F1- is bonded to four equivalent Pb3+ atoms to form a mixture of corner and edge-sharing FPb4 tetrahedra.

36 MATERIALS SCIENCE↗