Materials Data on CeUN2 by Materials Project
UCeN2 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. U3+ is bonded to six N3- atoms to form UN6 octahedra that share corners with six equivalent UN6 octahedra, edges with four equivalent UN6 octahedra, and edges with eight equivalent CeN6 octahedra. The corner-sharing octahedral tilt angles are 0°. All U–N bond lengths are 2.47 Å. Ce3+ is bonded to six N3- atoms to form CeN6 octahedra that share corners with six equivalent CeN6 octahedra, edges with four equivalent CeN6 octahedra, and edges with eight equivalent UN6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ce–N bond lengths are 2.47 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to two equivalent U3+ and four equivalent Ce3+ atoms to form a mixture of edge and corner-sharing NCe4U2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second N3- site, N3- is bonded to four equivalent U3+ and two equivalent Ce3+ atoms to form NCe2U4 octahedra that share corners with six equivalent NCe2U4 octahedra and edges with twelve NCe4U2 octahedra. The corner-sharing octahedral tilt angles are 0°.