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Materials Data on Ce4Se3N2 by Materials Project

Ce4N2Se3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Ce3+ sites. In the first Ce3+ site, Ce3+ is bonded in a 6-coordinate geometry to two equivalent N3- and four equivalent Se2- atoms. Both Ce–N bond lengths are 2.31 Å. There are two shorter (3.02 Å) and two longer (3.07 Å) Ce–Se bond lengths. In the second Ce3+ site, Ce3+ is bonded in a 6-coordinate geometry to two equivalent N3- and four Se2- atoms. Both Ce–N bond lengths are 2.30 Å. There are a spread of Ce–Se bond distances ranging from 2.95–3.18 Å. In the third Ce3+ site, Ce3+ is bonded in a 2-coordinate geometry to two equivalent N3- and five Se2- atoms. There are one shorter (2.25 Å) and one longer (2.33 Å) Ce–N bond lengths. There are a spread of Ce–Se bond distances ranging from 3.13–3.36 Å. N3- is bonded to four Ce3+ atoms to form NCe4 tetrahedra that share corners with four equivalent SeCe6 octahedra, an edgeedge with one SeCe6 octahedra, and edges with two equivalent NCe4 tetrahedra. The corner-sharing octahedra tilt angles range from 17–64°. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to six Ce3+ atoms to form SeCe6 octahedra that share corners with eight equivalent NCe4 tetrahedra, edges with two equivalent NCe4 tetrahedra, and faces with two equivalent SeCe6 octahedra. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to six Ce3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Ce4Se3N2 by Materials Project

Ce4N2Se3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Ce3+ sites. In the first Ce3+ site, Ce3+ is bonded in a 2-coordinate geometry to two equivalent N3- and five Se2- atoms. There are one shorter (2.30 Å) and one longer (2.33 Å) Ce–N bond lengths. There are a spread of Ce–Se bond distances ranging from 3.08–3.28 Å. In the second Ce3+ site, Ce3+ is bonded in a 2-coordinate geometry to two equivalent N3- and four Se2- atoms. There are one shorter (2.30 Å) and one longer (2.35 Å) Ce–N bond lengths. There are three shorter (2.99 Å) and one longer (3.03 Å) Ce–Se bond lengths. N3- is bonded to four Ce3+ atoms to form NCe4 tetrahedra that share corners with eight SeCe6 octahedra, corners with two equivalent NCe4 tetrahedra, edges with five SeCe6 octahedra, and an edgeedge with one NCe4 tetrahedra. The corner-sharing octahedra tilt angles range from 24–81°. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to six Ce3+ atoms to form distorted SeCe6 octahedra that share corners with ten equivalent SeCe6 octahedra, corners with four equivalent NCe4 tetrahedra, edges with two equivalent SeCe6 octahedra, edges with four equivalent NCe4 tetrahedra, and faces with two equivalent SeCe6 octahedra. The corner-sharing octahedra tilt angles range from 29–63°. In the second Se2- site, Se2- is bonded to six Ce3+ atoms to form distorted SeCe6 octahedra that share corners with seven SeCe6 octahedra, corners with six equivalent NCe4 tetrahedra, edges with six equivalent SeCe6 octahedra, edges with three equivalent NCe4 tetrahedra, and a faceface with one SeCe6 octahedra. The corner-sharing octahedra tilt angles range from 19–63°.

36 MATERIALS SCIENCE↗