Materials Data on UNbC2 by Materials Project
UNbC2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. U3+ is bonded to six equivalent C4- atoms to form UC6 octahedra that share corners with six equivalent NbC6 octahedra, edges with six equivalent UC6 octahedra, and edges with six equivalent NbC6 octahedra. The corner-sharing octahedral tilt angles are 4°. All U–C bond lengths are 2.42 Å. Nb5+ is bonded to six equivalent C4- atoms to form NbC6 octahedra that share corners with six equivalent UC6 octahedra, edges with six equivalent UC6 octahedra, and edges with six equivalent NbC6 octahedra. The corner-sharing octahedral tilt angles are 4°. All Nb–C bond lengths are 2.29 Å. C4- is bonded to three equivalent U3+ and three equivalent Nb5+ atoms to form a mixture of corner and edge-sharing CU3Nb3 octahedra. The corner-sharing octahedral tilt angles are 0°.