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DOE OSTI · 1355554

Materials Data on Eu2TiO4 by Materials Project

Abstract

Eu2TiO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Eu2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Eu–O bond distances ranging from 2.39–2.78 Å. Ti4+ is bonded to six O2- atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There is four shorter (1.96 Å) and two longer (2.03 Å) Ti–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Eu2+ and two equivalent Ti4+ atoms to form a mixture of distorted corner, edge, and face-sharing OEu4Ti2 octahedra. The corner-sharing octahedra tilt angles range from 0–55°. In the second O2- site, O2- is bonded to five equivalent Eu2+ and one Ti4+ atom to form distorted OEu5Ti octahedra that share corners with seventeen OEu4Ti2 octahedra, edges with eight equivalent OEu5Ti octahedra, and faces with four equivalent OEu4Ti2 octahedra. The corner-sharing octahedra tilt angles range from 0–55°.

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2020-07-18. Materials Data on Eu2TiO4 by Materials Project. https://doi.org/10.17188/1355554

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36 MATERIALS SCIENCE↗