Materials Data on Th2Mn17C2 by Materials Project

Abstract

Th2Mn17C2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Th is bonded in a distorted bent 120 degrees geometry to eight Mn and two equivalent C atoms. There are a spread of Th–Mn bond distances ranging from 2.97–3.40 Å. Both Th–C bond lengths are 2.57 Å. There are seven inequivalent Mn sites. In the first Mn site, Mn is bonded in a 12-coordinate geometry to three equivalent Th and nine Mn atoms. There are a spread of Mn–Mn bond distances ranging from 2.46–2.76 Å. In the second Mn site, Mn is bonded in a single-bond geometry to five Mn and one C atom. There are a spread of Mn–Mn bond distances ranging from 2.43–2.61 Å. The Mn–C bond length is 1.89 Å. In the third Mn site, Mn is bonded in a 12-coordinate geometry to ten Mn atoms. There are four shorter (2.42 Å) and two longer (2.62 Å) Mn–Mn bond lengths. In the fourth Mn site, Mn is bonded to two equivalent Th and ten Mn atoms to form distorted MnTh2Mn10 cuboctahedra that share corners with two equivalent MnTh2Mn10 cuboctahedra, corners with two equivalent CTh2Mn4 octahedra, faces with two equivalent MnTh2Mn10 cuboctahedra, and faces with two equivalent CTh2Mn4 octahedra. The corner-sharing octahedral tilt angles are 47°. There are a spread of Mn–Mn bond distances ranging from 2.40–2.66 Å. In the fifth Mn site, Mn is bonded in a distorted q6 geometry to two equivalent Th and ten Mn atoms. There are two shorter (2.36 Å) and two longer (2.60 Å) Mn–Mn bond lengths. In the sixth Mn site, Mn is bonded in a single-bond geometry to six Mn and one C atom. There are one shorter (2.65 Å) and one longer (2.68 Å) Mn–Mn bond lengths. The Mn–C bond length is 1.91 Å. In the seventh Mn site, Mn is bonded in a 1-coordinate geometry to one Th and thirteen Mn atoms. The Mn–Mn bond length is 2.35 Å. C is bonded to two equivalent Th and four Mn atoms to form CTh2Mn4 octahedra that share corners with two equivalent MnTh2Mn10 cuboctahedra, corners with two equivalent CTh2Mn4 octahedra, and faces with two equivalent MnTh2Mn10 cuboctahedra. The corner-sharing octahedral tilt angles are 64°.