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DOE OSTI · 1300732

Materials Data on La2Pt2O7 by Materials Project

Abstract

La2Pt2O7 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 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.36–2.84 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 2.36–2.59 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 2.40–2.58 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 2.49–2.83 Å. There are four inequivalent Pt4+ sites. In the first Pt4+ site, Pt4+ is bonded to six O2- atoms to form corner-sharing PtO6 octahedra. The corner-sharing octahedra tilt angles range from 35–38°. There are a spread of Pt–O bond distances ranging from 1.99–2.11 Å. In the second Pt4+ site, Pt4+ is bonded to six O2- atoms to form corner-sharing PtO6 octahedra. The corner-sharing octahedra tilt angles range from 29–38°. There are a spread of Pt–O bond distances ranging from 2.02–2.13 Å. In the third Pt4+ site, Pt4+ is bonded to six O2- atoms to form corner-sharing PtO6 octahedra. The corner-sharing octahedra tilt angles range from 35–39°. There are a spread of Pt–O bond distances ranging from 1.98–2.13 Å. In the fourth Pt4+ site, Pt4+ is bonded to six O2- atoms to form corner-sharing PtO6 octahedra. The corner-sharing octahedra tilt angles range from 29–39°. There are a spread of Pt–O bond distances ranging from 2.03–2.14 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to two La3+ and two Pt4+ atoms to form distorted OLa2Pt2 tetrahedra that share corners with five OLa3Pt tetrahedra, an edgeedge with one OLa2Pt2 tetrahedra, and an edgeedge with one OLa2Pt2 trigonal pyramid. In the second O2- site, O2- is bonded to three La3+ and one Pt4+ atom to form distorted OLa3Pt tetrahedra that share corners with five OLa2Pt2 tetrahedra, edges with four OLa3Pt tetrahedra, and an edgeedge with one OLa2Pt2 trigonal pyramid. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Pt4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and two Pt4+ atoms. In the fifth O2- site, O2- is bonded to three La3+ and one Pt4+ atom to form distorted OLa3Pt tetrahedra that share corners with seven OLa2Pt2 tetrahedra, corners with two equivalent OLa2Pt2 trigonal pyramids, and edges with three equivalent OLa3Pt tetrahedra. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to three La3+ and two equivalent Pt4+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Pt4+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two La3+ and one Pt4+ atom. In the ninth O2- site, O2- is bonded to two La3+ and two Pt4+ atoms to form a mixture of distorted corner and edge-sharing OLa2Pt2 tetrahedra. In the tenth O2- site, O2- is bonded to two La3+ and two Pt4+ atoms to form distorted OLa2Pt2 trigonal pyramids that share corners with six OLa3Pt tetrahedra and edges with three OLa2Pt2 tetrahedra. In the eleventh O2- site, O2- is bonded to two La3+ and two Pt4+ atoms to form a mixture of distorted corner and edge-sharing OLa2Pt2 tetrahedra. In the twelfth O2- site, O2- is bonded to three La3+ and one Pt4+ atom to form distorted OLa3Pt tetrahedra that share corners with nine OLa3Pt tetrahedra, corners with three equivalent OLa2Pt2 trigonal pyramids, and an edgeedge with one OLa3Pt tetrahedra. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to three La3+ and two equivalent Pt4+ atoms. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two La3+ and two Pt4+ atoms.

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2017-05-10. Materials Data on La2Pt2O7 by Materials Project. https://doi.org/10.17188/1300732

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