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DOE OSTI · 1742799

Materials Data on La7Nb3(W2O15)2 by Materials Project

Abstract

La7Nb3W4O30 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.41–2.95 Å. In the second La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.45–2.98 Å. In the third La3+ site, La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.42–2.91 Å. In the fourth La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share faces with four NbO6 octahedra and faces with four WO6 octahedra. There are a spread of La–O bond distances ranging from 2.56–2.77 Å. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four WO6 octahedra, and faces with two equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 35–36°. There are two shorter (2.01 Å) and four longer (2.05 Å) Nb–O bond lengths. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with two WO6 octahedra, and a faceface with one LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 32–36°. There are a spread of Nb–O bond distances ranging from 1.88–2.34 Å. There are two inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share a cornercorner with one WO6 octahedra, corners with two NbO6 octahedra, and a faceface with one LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 29–35°. There are a spread of W–O bond distances ranging from 1.85–2.18 Å. In the second W6+ site, W6+ is bonded to six O2- atoms to form distorted WO6 octahedra that share a cornercorner with one WO6 octahedra, corners with two NbO6 octahedra, and a faceface with one LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 29–35°. There are a spread of W–O bond distances ranging from 1.85–2.18 Å. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two La3+ and one Nb5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two La3+ and one W6+ atom. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two La3+ and one W6+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+, one Nb5+, and one W6+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two W6+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+, one Nb5+, and one W6+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two La3+ and one Nb5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two La3+ and one W6+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two La3+ and one W6+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one Nb5+ atom. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one W6+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to three La3+ and one W6+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+, one Nb5+, and one W6+ atom. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to two La3+ and two Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+, one Nb5+, and one W6+ atom.

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BibTeXRIS

2020-04-29. Materials Data on La7Nb3(W2O15)2 by Materials Project. https://doi.org/10.17188/1742799

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