Materials Data on Sm2Mn17C2 by Materials Project

Abstract

Sm2Mn17C2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Sm is bonded in a distorted bent 120 degrees geometry to nine Mn and two equivalent C atoms. There are a spread of Sm–Mn bond distances ranging from 3.00–3.42 Å. Both Sm–C bond lengths are 2.53 Å. There are seven inequivalent Mn sites. In the first Mn site, Mn is bonded in a 1-coordinate geometry to one Sm and thirteen Mn atoms. There are a spread of Mn–Mn bond distances ranging from 2.34–2.70 Å. In the second Mn site, Mn is bonded to two equivalent Sm and ten Mn atoms to form distorted MnSm2Mn10 cuboctahedra that share corners with four MnSm2Mn10 cuboctahedra, corners with four equivalent CSm2Mn4 octahedra, edges with three MnSm2Mn10 cuboctahedra, edges with two equivalent CSm2Mn4 octahedra, and faces with three MnSm2Mn10 cuboctahedra. The corner-sharing octahedra tilt angles range from 22–28°. There are a spread of Mn–Mn bond distances ranging from 2.41–2.68 Å. In the third Mn site, Mn is bonded in a single-bond geometry to six Mn and one C atom. There are a spread of Mn–Mn bond distances ranging from 2.41–2.58 Å. The Mn–C bond length is 1.89 Å. In the fourth 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 2.42–2.68 Å. The Mn–C bond length is 1.90 Å. In the fifth Mn site, Mn is bonded in a 12-coordinate geometry to three equivalent Sm and nine Mn atoms. Both Mn–Mn bond lengths are 2.44 Å. In the sixth Mn site, Mn is bonded in a 12-coordinate geometry to two equivalent Sm and ten Mn atoms. In the seventh Mn site, Mn is bonded to two equivalent Sm and ten Mn atoms to form distorted MnSm2Mn10 cuboctahedra that share corners with four MnSm2Mn10 cuboctahedra, corners with two equivalent CSm2Mn4 octahedra, edges with two equivalent MnSm2Mn10 cuboctahedra, faces with four MnSm2Mn10 cuboctahedra, and faces with two equivalent CSm2Mn4 octahedra. The corner-sharing octahedral tilt angles are 48°. C is bonded to two equivalent Sm and four Mn atoms to form CSm2Mn4 octahedra that share corners with six MnSm2Mn10 cuboctahedra, corners with two equivalent CSm2Mn4 octahedra, edges with two equivalent MnSm2Mn10 cuboctahedra, and faces with two equivalent MnSm2Mn10 cuboctahedra. The corner-sharing octahedral tilt angles are 63°.