Materials Data on CeU4C5 by Materials Project

Abstract

U4CeC5 is Caswellsilverite-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent U+4.25+ sites. In the first U+4.25+ site, U+4.25+ is bonded to six C4- atoms to form UC6 octahedra that share corners with six UC6 octahedra, edges with four equivalent CeC6 octahedra, and edges with eight UC6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of U–C bond distances ranging from 2.47–2.50 Å. In the second U+4.25+ site, U+4.25+ is bonded to six C4- atoms to form UC6 octahedra that share a cornercorner with one CeC6 octahedra, corners with five UC6 octahedra, and edges with twelve UC6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of U–C bond distances ranging from 2.37–2.50 Å. Ce3+ is bonded to six C4- atoms to form CeC6 octahedra that share corners with two equivalent UC6 octahedra, corners with four equivalent CeC6 octahedra, edges with four equivalent CeC6 octahedra, and edges with eight equivalent UC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.50 Å) and two longer (2.61 Å) Ce–C bond lengths. There are four inequivalent C4- sites. In the first C4- site, C4- is bonded to six U+4.25+ atoms to form a mixture of edge and corner-sharing CU6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second C4- site, C4- is bonded to five U+4.25+ and one Ce3+ atom to form a mixture of edge and corner-sharing CCeU5 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. In the third C4- site, C4- is bonded to two equivalent U+4.25+ and four equivalent Ce3+ atoms to form CCe4U2 octahedra that share corners with six CU6 octahedra and edges with twelve CCeU5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth C4- site, C4- is bonded to two equivalent U+4.25+ and four equivalent Ce3+ atoms to form CCe4U2 octahedra that share corners with six CU6 octahedra and edges with twelve CCe4U2 octahedra. The corner-sharing octahedral tilt angles are 0°. Both C–U bond lengths are 2.47 Å. All C–Ce bond lengths are 2.50 Å.