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DOE OSTI · 1301518

Materials Data on La2Bi2O7 by Materials Project

Abstract

La2Bi2O7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are four inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of La–O bond distances ranging from 2.31–2.64 Å. In the second La3+ site, La3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of La–O bond distances ranging from 2.40–2.69 Å. In the third La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.34–2.77 Å. In the fourth La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.47–2.81 Å. There are four inequivalent Bi4+ sites. In the first Bi4+ site, Bi4+ is bonded to six O2- atoms to form corner-sharing BiO6 octahedra. The corner-sharing octahedra tilt angles range from 37–50°. There are a spread of Bi–O bond distances ranging from 2.11–2.27 Å. In the second Bi4+ site, Bi4+ is bonded to six O2- atoms to form corner-sharing BiO6 octahedra. The corner-sharing octahedra tilt angles range from 36–51°. There are a spread of Bi–O bond distances ranging from 2.25–2.40 Å. In the third Bi4+ site, Bi4+ is bonded to six O2- atoms to form corner-sharing BiO6 octahedra. The corner-sharing octahedra tilt angles range from 37–51°. There are a spread of Bi–O bond distances ranging from 2.10–2.34 Å. In the fourth Bi4+ site, Bi4+ is bonded to six O2- atoms to form corner-sharing BiO6 octahedra. The corner-sharing octahedra tilt angles range from 33–51°. There are a spread of Bi–O bond distances ranging from 2.21–2.41 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Bi4+ atoms. In the second O2- site, O2- is bonded to three La3+ and one Bi4+ atom to form a mixture of distorted corner and edge-sharing OLa3Bi tetrahedra. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one La3+ and two Bi4+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one La3+ and two Bi4+ atoms. In the fifth O2- site, O2- is bonded to three La3+ and one Bi4+ atom to form a mixture of distorted corner and edge-sharing OLa3Bi tetrahedra. In the sixth O2- site, O2- is bonded to two La3+ and two equivalent Bi4+ atoms to form a mixture of distorted corner and edge-sharing OLa2Bi2 trigonal pyramids. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Bi4+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two La3+ and one Bi4+ atom. In the ninth O2- site, O2- is bonded to two La3+ and two Bi4+ atoms to form a mixture of distorted corner and edge-sharing OLa2Bi2 trigonal pyramids. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Bi4+ atoms. In the eleventh O2- site, O2- is bonded to two La3+ and two Bi4+ atoms to form a mixture of distorted corner and edge-sharing OLa2Bi2 tetrahedra. In the twelfth O2- site, O2- is bonded to three La3+ and one Bi4+ atom to form distorted OLa3Bi tetrahedra that share corners with eight OLa3Bi tetrahedra, a cornercorner with one OLa2Bi2 trigonal pyramid, and an edgeedge with one OLa3Bi tetrahedra. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two equivalent Bi4+ atoms. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Bi4+ atoms.

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2020-07-15. Materials Data on La2Bi2O7 by Materials Project. https://doi.org/10.17188/1301518

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