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DOE OSTI · 1289051

Materials Data on La2(BiO2)7 by Materials Project

Abstract

La2(BiO2)7 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of one La2(BiO2)7 sheet oriented in the (0, 0, 1) direction. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to six O2- atoms to form distorted LaO6 octahedra that share corners with three BiO5 square pyramids and corners with three BiO5 trigonal bipyramids. There are a spread of La–O bond distances ranging from 2.44–2.54 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 2.35–2.66 Å. There are seven inequivalent Bi+3.14+ sites. In the first Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form distorted BiO5 square pyramids that share a cornercorner with one LaO6 octahedra, corners with four BiO5 square pyramids, and edges with two BiO5 square pyramids. The corner-sharing octahedral tilt angles are 57°. There are a spread of Bi–O bond distances ranging from 2.17–2.69 Å. In the second Bi+3.14+ site, Bi+3.14+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.19–2.67 Å. In the third Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form distorted BiO5 trigonal bipyramids that share a cornercorner with one LaO6 octahedra, corners with four BiO5 trigonal bipyramids, and edges with two BiO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 69°. There are a spread of Bi–O bond distances ranging from 2.15–2.71 Å. In the fourth Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form distorted BiO5 square pyramids that share a cornercorner with one LaO6 octahedra, corners with four BiO5 square pyramids, and edges with two BiO5 square pyramids. The corner-sharing octahedral tilt angles are 59°. There are a spread of Bi–O bond distances ranging from 2.15–2.42 Å. In the fifth Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form distorted BiO5 trigonal bipyramids that share a cornercorner with one LaO6 octahedra, corners with four BiO5 trigonal bipyramids, and edges with two BiO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 70°. There are a spread of Bi–O bond distances ranging from 2.15–2.75 Å. In the sixth Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form distorted BiO5 trigonal bipyramids that share a cornercorner with one LaO6 octahedra, corners with four BiO5 trigonal bipyramids, and edges with two BiO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 70°. There are a spread of Bi–O bond distances ranging from 2.16–2.64 Å. In the seventh Bi+3.14+ site, Bi+3.14+ is bonded to five O2- atoms to form distorted BiO5 square pyramids that share a cornercorner with one LaO6 octahedra, corners with four BiO5 square pyramids, and edges with two BiO5 square pyramids. The corner-sharing octahedral tilt angles are 55°. There are a spread of Bi–O bond distances ranging from 2.16–2.68 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to two La3+ and two Bi+3.14+ atoms to form a mixture of distorted edge and corner-sharing OLa2Bi2 tetrahedra. In the second O2- site, O2- is bonded in a 3-coordinate geometry to three Bi+3.14+ atoms. In the third O2- site, O2- is bonded to two La3+ and two Bi+3.14+ atoms to form a mixture of edge and corner-sharing OLa2Bi2 tetrahedra. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to three Bi+3.14+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Bi+3.14+ atoms. In the sixth O2- site, O2- is bonded to two La3+ and two Bi+3.14+ atoms to form a mixture of distorted edge and corner-sharing OLa2Bi2 tetrahedra. In the seventh O2- site, O2- is bonded to four Bi+3.14+ atoms to form a mixture of edge and corner-sharing OBi4 tetrahedra. In the eighth O2- site, O2- is bonded to two La3+ and two Bi+3.14+ atoms to form a mixture of edge and corner-sharing OLa2Bi2 tetrahedra. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to three Bi+3.14+ atoms. In the tenth O2- site, O2- is bonded to one La3+ and three Bi+3.14+ atoms to form a mixture of edge and corner-sharing OLaBi3 tetrahedra. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to three Bi+3.14+ atoms. In the twelfth O2- site, O2- is bonded to two La3+ and two Bi+3.14+ atoms to form a mixture of edge and corner-sharing OLa2Bi2 tetrahedra. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Bi+3.14+ atoms. In the fourteenth O2- site, O2- is bonded to two La3+ and two Bi+3.14+ atoms to form a mixture of distorted edge and corner-sharing OLa2Bi2 tetrahedra.

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2020-05-02. Materials Data on La2(BiO2)7 by Materials Project. https://doi.org/10.17188/1289051

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