Materials Data on Th5C4 by Materials Project

Abstract

Th5C4 is MAX Phase-derived structured and crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of three Th5C4 sheets oriented in the (0, 0, 1) direction. there are three inequivalent Th sites. In the first Th site, Th is bonded to six C atoms to form a mixture of edge and corner-sharing ThC6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are three shorter (2.62 Å) and three longer (2.79 Å) Th–C bond lengths. In the second Th site, Th is bonded to six equivalent C atoms to form a mixture of edge and corner-sharing ThC6 octahedra. The corner-sharing octahedral tilt angles are 2°. All Th–C bond lengths are 2.70 Å. In the third Th site, Th is bonded in a 3-coordinate geometry to three equivalent C atoms. All Th–C bond lengths are 2.50 Å. There are two inequivalent C sites. In the first C site, C is bonded to six Th atoms to form a mixture of edge and corner-sharing CTh6 octahedra. The corner-sharing octahedral tilt angles are 5°. In the second C site, C is bonded to six Th atoms to form a mixture of edge and corner-sharing CTh6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°.