Materials Data on SmUN2 by Materials Project
USmN2 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 SmN6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.46 Å) and four longer (2.48 Å) U–N bond lengths. Sm3+ is bonded to six N3- atoms to form SmN6 octahedra that share corners with six equivalent SmN6 octahedra, edges with four equivalent SmN6 octahedra, and edges with eight equivalent UN6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.46 Å) and four longer (2.48 Å) Sm–N bond lengths. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded to four equivalent U3+ and two equivalent Sm3+ atoms to form a mixture of edge and corner-sharing NSm2U4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second N3- site, N3- is bonded to two equivalent U3+ and four equivalent Sm3+ atoms to form NSm4U2 octahedra that share corners with six equivalent NSm4U2 octahedra and edges with twelve NSm2U4 octahedra. The corner-sharing octahedral tilt angles are 0°.