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DOE OSTI · 1289596

Materials Data on Hf2N2O by Materials Project

Abstract

Hf2ON2 is Ilmenite-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to four N3- and two O2- atoms to form a mixture of distorted face, edge, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 44–64°. There are a spread of Hf–N bond distances ranging from 2.07–2.25 Å. There are one shorter (2.16 Å) and one longer (2.39 Å) Hf–O bond lengths. In the second Hf4+ site, Hf4+ is bonded to four N3- and two O2- atoms to form a mixture of distorted face, edge, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 42–66°. There are a spread of Hf–N bond distances ranging from 2.09–2.33 Å. There are one shorter (2.08 Å) and one longer (2.27 Å) Hf–O bond lengths. In the third Hf4+ site, Hf4+ is bonded to four N3- and two O2- atoms to form a mixture of distorted face, edge, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 46–66°. There are a spread of Hf–N bond distances ranging from 2.09–2.29 Å. There are one shorter (2.14 Å) and one longer (2.32 Å) Hf–O bond lengths. In the fourth Hf4+ site, Hf4+ is bonded to four N3- and two O2- atoms to form a mixture of distorted face, edge, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 44–66°. There are a spread of Hf–N bond distances ranging from 2.04–2.23 Å. There are one shorter (2.17 Å) and one longer (2.44 Å) Hf–O bond lengths. In the fifth Hf4+ site, Hf4+ is bonded to four N3- and two O2- atoms to form a mixture of distorted face, edge, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 42–64°. There are a spread of Hf–N bond distances ranging from 2.06–2.24 Å. There are one shorter (2.15 Å) and one longer (2.35 Å) Hf–O bond lengths. In the sixth Hf4+ site, Hf4+ is bonded to four N3- and two O2- atoms to form a mixture of distorted face, edge, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 47–67°. There are a spread of Hf–N bond distances ranging from 2.09–2.30 Å. There are one shorter (2.08 Å) and one longer (2.26 Å) Hf–O bond lengths. In the seventh Hf4+ site, Hf4+ is bonded to four N3- and two O2- atoms to form a mixture of distorted face, edge, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 45–67°. There are a spread of Hf–N bond distances ranging from 2.04–2.24 Å. There are one shorter (2.17 Å) and one longer (2.38 Å) Hf–O bond lengths. In the eighth Hf4+ site, Hf4+ is bonded to four N3- and two O2- atoms to form a mixture of distorted face, edge, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 46–66°. There are a spread of Hf–N bond distances ranging from 2.08–2.30 Å. There are one shorter (2.13 Å) and one longer (2.32 Å) Hf–O bond lengths. There are eight inequivalent N3- sites. In the first N3- site, N3- is bonded to four Hf4+ atoms to form a mixture of distorted edge and corner-sharing NHf4 trigonal pyramids. In the second N3- site, N3- is bonded to four Hf4+ atoms to form a mixture of distorted edge and corner-sharing NHf4 trigonal pyramids. In the third N3- site, N3- is bonded to four Hf4+ atoms to form a mixture of distorted edge and corner-sharing NHf4 trigonal pyramids. In the fourth N3- site, N3- is bonded in a distorted see-saw-like geometry to four Hf4+ atoms. In the fifth N3- site, N3- is bonded to four Hf4+ atoms to form a mixture of distorted edge and corner-sharing NHf4 trigonal pyramids. In the sixth N3- site, N3- is bonded to four Hf4+ atoms to form a mixture of distorted edge and corner-sharing NHf4 trigonal pyramids. In the seventh N3- site, N3- is bonded to four Hf4+ atoms to form a mixture of distorted edge and corner-sharing NHf4 trigonal pyramids. In the eighth N3- site, N3- is bonded in a distorted see-saw-like geometry to four Hf4+ atoms. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to four Hf4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to four Hf4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to four Hf4+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to four Hf4+ atoms.

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BibTeXRIS

2020-07-15. Materials Data on Hf2N2O by Materials Project. https://doi.org/10.17188/1289596

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36 MATERIALS SCIENCE↗