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DOE OSTI · 1186839

Materials Data on Ca2BN2F by Materials Project

Abstract

Ca2BN2F crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to three N3- and three equivalent F1- atoms to form distorted CaN3F3 octahedra that share corners with five equivalent CaN5F octahedra and edges with seven CaN3F3 octahedra. The corner-sharing octahedra tilt angles range from 2–71°. There are one shorter (2.33 Å) and two longer (2.58 Å) Ca–N bond lengths. There are two shorter (2.37 Å) and one longer (2.40 Å) Ca–F bond lengths. In the second Ca2+ site, Ca2+ is bonded to five N3- and one F1- atom to form a mixture of edge and corner-sharing CaN5F octahedra. The corner-sharing octahedra tilt angles range from 2–71°. There are a spread of Ca–N bond distances ranging from 2.39–2.65 Å. The Ca–F bond length is 2.47 Å. B3+ is bonded in a linear geometry to two N3- atoms. There is one shorter (1.33 Å) and one longer (1.35 Å) B–N bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted single-bond geometry to five Ca2+ and one B3+ atom. In the second N3- site, N3- is bonded in a 4-coordinate geometry to three Ca2+ and one B3+ atom. F1- is bonded to four Ca2+ atoms to form a mixture of edge and corner-sharing FCa4 tetrahedra.

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2020-07-15. Materials Data on Ca2BN2F by Materials Project. https://doi.org/10.17188/1186839

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36 MATERIALS SCIENCE↗