Materials Data on SmMgS3 by Materials Project
MgSmS3 is Ilmenite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Mg2+ is bonded to six S+1.67- atoms to form distorted MgS6 octahedra that share corners with four equivalent SmS6 pentagonal pyramids, edges with three equivalent MgS6 octahedra, and edges with four equivalent SmS6 pentagonal pyramids. There are a spread of Mg–S bond distances ranging from 2.55–2.87 Å. Sm3+ is bonded to six S+1.67- atoms to form distorted SmS6 pentagonal pyramids that share corners with four equivalent MgS6 octahedra, edges with four equivalent MgS6 octahedra, an edgeedge with one SmS6 pentagonal pyramid, and a faceface with one SmS6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 38–48°. There are a spread of Sm–S bond distances ranging from 2.73–2.98 Å. There are two inequivalent S+1.67- sites. In the first S+1.67- site, S+1.67- is bonded in a 4-coordinate geometry to two equivalent Mg2+ and two equivalent Sm3+ atoms. In the second S+1.67- site, S+1.67- is bonded to two equivalent Mg2+ and two equivalent Sm3+ atoms to form edge-sharing SSm2Mg2 trigonal pyramids.