DOI: 10.17188/1290347
title: Materials Data on Hf2N2O by Materials Project

description: 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 edge, face, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 43–66°. There are a spread of Hf–N bond distances ranging from 2.09–2.37 Å. There are one shorter (2.08 Å) and one longer (2.24 Å) Hf–O bond lengths. In the second Hf4+ site, Hf4+ is bonded in a 6-coordinate geometry to four N3- and two O2- atoms. There are a spread of Hf–N bond distances ranging from 2.03–2.22 Å. There are one shorter (2.16 Å) and one longer (2.52 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 edge, face, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 44–52°. There are a spread of Hf–N bond distances ranging from 2.03–2.21 Å. There are one shorter (2.16 Å) and one longer (2.51 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 edge, face, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 43–68°. There are a spread of Hf–N bond distances ranging from 2.04–2.28 Å. There are one shorter (2.16 Å) and one longer (2.41 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 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 2.09–2.37 Å. There are one shorter (2.08 Å) and one longer (2.24 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 edge, face, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 42–68°. There are a spread of Hf–N bond distances ranging from 2.03–2.28 Å. There are one shorter (2.16 Å) and one longer (2.41 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 edge, face, and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 47–68°. There are a spread of Hf–N bond distances ranging from 2.11–2.27 Å. There are one shorter (2.07 Å) and one longer (2.30 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 and corner-sharing HfN4O2 octahedra. The corner-sharing octahedra tilt angles range from 47–68°. There are a spread of Hf–N bond distances ranging from 2.11–2.27 Å. There are one shorter (2.07 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 in a distorted see-saw-like geometry to four Hf4+ atoms. In the second N3- site, N3- is bonded in a 4-coordinate geometry to four Hf4+ atoms. In the third N3- site, N3- is bonded in a 4-coordinate geometry to four Hf4+ atoms. 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 distorted NHf4 trigonal pyramids that share corners with two equivalent OHf4 trigonal pyramids, corners with six NHf4 trigonal pyramids, an edgeedge with one NHf4 trigonal pyramid, and an edgeedge with one OHf4 trigonal pyramid. In the sixth N3- site, N3- is bonded to four Hf4+ atoms to form distorted NHf4 trigonal pyramids that share corners with four NHf4 trigonal pyramids and an edgeedge with one OHf4 trigonal pyramid. In the seventh N3- site, N3- is bonded to four Hf4+ atoms to form distorted NHf4 trigonal pyramids that share corners with four NHf4 trigonal pyramids and an edgeedge with one OHf4 trigonal pyramid. In the eighth N3- site, N3- is bonded to four Hf4+ atoms to form distorted NHf4 trigonal pyramids that share corners with two equivalent OHf4 trigonal pyramids, corners with six NHf4 trigonal pyramids, an edgeedge with one NHf4 trigonal pyramid, and an edgeedge with one OHf4 trigonal pyramid. 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 to four Hf4+ atoms to form distorted OHf4 trigonal pyramids that share corners with four NHf4 trigonal pyramids and edges with four NHf4 trigonal pyramids. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to four Hf4+ atoms.