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DOE OSTI · 1289601

Materials Data on La3Ti2N3O4 by Materials Project

Abstract

La3Ti2N3O4 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to eight N3- and four equivalent O2- atoms to form LaN8O4 cuboctahedra that share corners with four equivalent LaN8O4 cuboctahedra, faces with four equivalent LaN8O4 cuboctahedra, and faces with eight equivalent TiN3O3 octahedra. There are four shorter (2.80 Å) and four longer (2.87 Å) La–N bond lengths. All La–O bond lengths are 2.92 Å. In the second La3+ site, La3+ is bonded in a 9-coordinate geometry to two equivalent N3- and seven O2- atoms. Both La–N bond lengths are 2.57 Å. There are a spread of La–O bond distances ranging from 2.35–2.84 Å. Ti4+ is bonded to three N3- and three O2- atoms to form TiN3O3 octahedra that share corners with five equivalent TiN3O3 octahedra and faces with four equivalent LaN8O4 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–11°. There is one shorter (1.94 Å) and two longer (2.01 Å) Ti–N bond length. There are two shorter (1.96 Å) and one longer (2.32 Å) Ti–O bond lengths. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted linear geometry to four equivalent La3+ and two equivalent Ti4+ atoms. In the second N3- site, N3- is bonded in a 2-coordinate geometry to four La3+ and two equivalent Ti4+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four La3+ and two equivalent Ti4+ atoms. In the second O2- site, O2- is bonded in a 6-coordinate geometry to five equivalent La3+ and one Ti4+ atom.

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2020-07-22. Materials Data on La3Ti2N3O4 by Materials Project. https://doi.org/10.17188/1289601

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36 MATERIALS SCIENCE↗