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DOE OSTI · 1711825

Materials Data on Nb4Pb3(O6F)2 by Materials Project

Abstract

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.

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2020-04-29. Materials Data on Nb4Pb3(O6F)2 by Materials Project. https://doi.org/10.17188/1711825

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