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DOE OSTI · 1355286

Materials Data on Eu2AlNO3 by Materials Project

Abstract

Eu2AlNO3 is (La,Ba)CuO4-derived structured and crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. there are two inequivalent Eu3+ sites. In the first Eu3+ site, Eu3+ is bonded in a 9-coordinate geometry to four equivalent N3- and five O2- atoms. All Eu–N bond lengths are 2.66 Å. There are one shorter (2.39 Å) and four longer (2.61 Å) Eu–O bond lengths. In the second Eu3+ site, Eu3+ is bonded in a 9-coordinate geometry to one N3- and eight O2- atoms. The Eu–N bond length is 2.36 Å. There are four shorter (2.56 Å) and four longer (2.66 Å) Eu–O bond lengths. Al3+ is bonded to one N3- and five O2- atoms to form corner-sharing AlNO5 octahedra. The corner-sharing octahedral tilt angles are 1°. The Al–N bond length is 2.10 Å. There is four shorter (1.87 Å) and one longer (2.03 Å) Al–O bond length. N3- is bonded to five Eu3+ and one Al3+ atom to form distorted NEu5Al octahedra that share a cornercorner with one OEu5Al octahedra, corners with four equivalent NEu5Al octahedra, edges with four equivalent NEu5Al octahedra, and edges with four equivalent OEu5Al octahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four Eu3+ and two equivalent Al3+ atoms. In the second O2- site, O2- is bonded to five Eu3+ and one Al3+ atom to form distorted OEu5Al octahedra that share a cornercorner with one NEu5Al octahedra, corners with four equivalent OEu5Al octahedra, edges with four equivalent NEu5Al octahedra, and edges with four equivalent OEu5Al octahedra. The corner-sharing octahedra tilt angles range from 0–11°.

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2020-07-18. Materials Data on Eu2AlNO3 by Materials Project. https://doi.org/10.17188/1355286

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36 MATERIALS SCIENCE↗