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DOE OSTI · 1757764

Materials Data on SrCeN2 by Materials Project

Abstract

SrCeN2 is Caswellsilverite-like structured and crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Sr2+ is bonded to six N3- atoms to form SrN6 octahedra that share corners with two equivalent CeN6 octahedra, corners with four equivalent SrN6 octahedra, edges with four equivalent SrN6 octahedra, and edges with eight equivalent CeN6 octahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are four shorter (2.63 Å) and two longer (2.88 Å) Sr–N bond lengths. Ce4+ is bonded to six N3- atoms to form CeN6 octahedra that share corners with two equivalent SrN6 octahedra, corners with four equivalent CeN6 octahedra, edges with four equivalent CeN6 octahedra, and edges with eight equivalent SrN6 octahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are two shorter (2.27 Å) and four longer (2.63 Å) Ce–N bond lengths. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded to three equivalent Sr2+ and three equivalent Ce4+ atoms to form a mixture of distorted corner and edge-sharing NSr3Ce3 octahedra. The corner-sharing octahedra tilt angles range from 0–13°. In the second N3- site, N3- is bonded to three equivalent Sr2+ and three equivalent Ce4+ atoms to form a mixture of distorted corner and edge-sharing NSr3Ce3 octahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are two shorter (2.63 Å) and one longer (2.88 Å) N–Sr bond lengths. In the third N3- site, N3- is bonded to three equivalent Sr2+ and three equivalent Ce4+ atoms to form a mixture of distorted corner and edge-sharing NSr3Ce3 octahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are one shorter (2.27 Å) and two longer (2.63 Å) N–Ce bond lengths. In the fourth N3- site, N3- is bonded to three equivalent Sr2+ and three equivalent Ce4+ atoms to form a mixture of distorted corner and edge-sharing NSr3Ce3 octahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are two shorter (2.63 Å) and one longer (2.88 Å) N–Sr bond lengths. There are one shorter (2.27 Å) and two longer (2.63 Å) N–Ce bond lengths.

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2020-09-03. Materials Data on SrCeN2 by Materials Project. https://doi.org/10.17188/1757764

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