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DOE OSTI · 1271036

Materials Data on La2Ti2O7 by Materials Project

Abstract

La2Ti2O7 is Pb (Zr_0.50 Ti_0.48) O_3-like structured and 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 7-coordinate geometry to seven O2- atoms. There are a spread of La–O bond distances ranging from 2.39–2.53 Å. In the second 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 2.44–2.87 Å. In the third La3+ site, La3+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of La–O bond distances ranging from 2.38–3.04 Å. In the fourth 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 2.42–2.95 Å. There are four inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 16–42°. There are a spread of Ti–O bond distances ranging from 1.79–2.34 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 15–38°. There are a spread of Ti–O bond distances ranging from 1.82–2.29 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 15–42°. There are a spread of Ti–O bond distances ranging from 1.82–2.32 Å. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 16–38°. There are a spread of Ti–O bond distances ranging from 1.84–2.28 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to three La3+ and one Ti4+ atom to form a mixture of distorted edge and corner-sharing OLa3Ti tetrahedra. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Ti4+ atoms. In the third O2- site, O2- is bonded to two La3+ and two Ti4+ atoms to form distorted OLa2Ti2 tetrahedra that share corners with five OLa3Ti tetrahedra and an edgeedge with one OLa2Ti2 tetrahedra. In the fourth O2- site, O2- is bonded to three La3+ and one Ti4+ atom to form a mixture of distorted edge and corner-sharing OLa3Ti tetrahedra. In the fifth O2- site, O2- is bonded to two La3+ and two Ti4+ atoms to form a mixture of distorted edge and corner-sharing OLa2Ti2 tetrahedra. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two La3+ and two Ti4+ atoms. In the seventh O2- site, O2- is bonded to three La3+ and one Ti4+ atom to form distorted OLa3Ti tetrahedra that share corners with five OLa2Ti2 tetrahedra and edges with four OLa3Ti tetrahedra. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to three La3+ and two equivalent Ti4+ atoms. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two La3+ and one Ti4+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two Ti4+ atoms. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to three La3+ and two equivalent Ti4+ atoms. In the twelfth O2- site, O2- is bonded to two La3+ and two Ti4+ atoms to form a mixture of distorted edge and corner-sharing OLa2Ti2 tetrahedra. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to three La3+ and two Ti4+ atoms. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to two La3+ and two Ti4+ atoms.

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2020-05-02. Materials Data on La2Ti2O7 by Materials Project. https://doi.org/10.17188/1271036

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