Materials Data on U4B3C5 by Materials Project

Abstract

U4B3C5 crystallizes in the orthorhombic Pmm2 space group. The structure is two-dimensional and consists of one U4B3C5 sheet oriented in the (0, 0, 1) direction. there are four inequivalent U+4.25+ sites. In the first U+4.25+ site, U+4.25+ is bonded to five C4- atoms to form a mixture of edge and corner-sharing UC5 square pyramids. There are one shorter (2.37 Å) and four longer (2.46 Å) U–C bond lengths. In the second U+4.25+ site, U+4.25+ is bonded in a 7-coordinate geometry to seven C4- atoms. There are a spread of U–C bond distances ranging from 2.35–2.71 Å. In the third U+4.25+ site, U+4.25+ is bonded to five C4- atoms to form a mixture of distorted edge and corner-sharing UC5 square pyramids. There are one shorter (2.33 Å) and four longer (2.46 Å) U–C bond lengths. In the fourth U+4.25+ site, U+4.25+ is bonded to five C4- atoms to form a mixture of edge and corner-sharing UC5 square pyramids. There are one shorter (2.36 Å) and four longer (2.46 Å) U–C bond lengths. There are three inequivalent B1+ sites. In the first B1+ site, B1+ is bonded in a single-bond geometry to one C4- atom. The B–C bond length is 1.58 Å. In the second B1+ site, B1+ is bonded in a single-bond geometry to one C4- atom. The B–C bond length is 1.58 Å. In the third B1+ site, B1+ is bonded in a trigonal planar geometry to three C4- atoms. There is one shorter (1.57 Å) and two longer (1.79 Å) B–C bond length. There are five inequivalent C4- sites. In the first C4- site, C4- is bonded to five U+4.25+ and one C4- atom to form CU5C octahedra that share corners with four equivalent CU5C octahedra and edges with eight CU5B octahedra. The corner-sharing octahedral tilt angles are 14°. The C–C bond length is 1.49 Å. In the second C4- site, C4- is bonded to five U+4.25+ and one B1+ atom to form a mixture of distorted edge and corner-sharing CU5B octahedra. The corner-sharing octahedral tilt angles are 16°. In the third C4- site, C4- is bonded to five U+4.25+ and one B1+ atom to form a mixture of distorted edge and corner-sharing CU5B octahedra. The corner-sharing octahedral tilt angles are 16°. In the fourth C4- site, C4- is bonded to five U+4.25+ and one B1+ atom to form a mixture of distorted edge and corner-sharing CU5B octahedra. The corner-sharing octahedral tilt angles are 16°. In the fifth C4- site, C4- is bonded in a 3-coordinate geometry to two equivalent U+4.25+, two equivalent B1+, and one C4- atom.