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DOE OSTI · 1282267

Materials Data on La2Ti2O7 by Materials Project

Abstract

La2Ti2O7 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are two 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 2.42–2.95 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 2.41–2.63 Å. There are two 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 octahedral tilt angles are 22°. There are a spread of Ti–O bond distances ranging from 1.80–2.36 Å. In the second Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.78–2.40 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent La3+ and one Ti4+ atom to form distorted corner-sharing OLa3Ti tetrahedra. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent La3+ and two Ti4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two La3+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and two equivalent Ti4+ atoms. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent La3+ and two equivalent Ti4+ atoms. In the sixth O2- site, O2- is bonded to two equivalent La3+ and two Ti4+ atoms to form distorted corner-sharing OLa2Ti2 tetrahedra. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent La3+ and one Ti4+ atom.

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2020-07-14. Materials Data on La2Ti2O7 by Materials Project. https://doi.org/10.17188/1282267

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36 MATERIALS SCIENCE↗