Materials Data on Lu2MgS4 by Materials Project

Abstract

MgLu2S4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Mg2+ is bonded to five S2- atoms to form MgS5 square pyramids that share corners with four LuS6 octahedra, edges with four LuS6 octahedra, and edges with four equivalent MgS5 square pyramids. The corner-sharing octahedra tilt angles range from 6–9°. There are three shorter (2.62 Å) and two longer (2.67 Å) Mg–S bond lengths. There are two inequivalent Lu3+ sites. In the first Lu3+ site, Lu3+ is bonded to six S2- atoms to form LuS6 octahedra that share corners with three equivalent LuS6 octahedra, corners with two equivalent MgS5 square pyramids, edges with six LuS6 octahedra, and an edgeedge with one MgS5 square pyramid. The corner-sharing octahedra tilt angles range from 54–59°. There are a spread of Lu–S bond distances ranging from 2.66–2.77 Å. In the second Lu3+ site, Lu3+ is bonded to six S2- atoms to form LuS6 octahedra that share corners with three equivalent LuS6 octahedra, corners with two equivalent MgS5 square pyramids, edges with four LuS6 octahedra, and edges with three equivalent MgS5 square pyramids. The corner-sharing octahedra tilt angles range from 54–59°. There are a spread of Lu–S bond distances ranging from 2.62–2.75 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to three equivalent Mg2+ and two equivalent Lu3+ atoms to form a mixture of edge and corner-sharing SLu2Mg3 square pyramids. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Lu3+ atoms. In the third S2- site, S2- is bonded in a 3-coordinate geometry to three Lu3+ atoms. In the fourth S2- site, S2- is bonded to two equivalent Mg2+ and three Lu3+ atoms to form SLu3Mg2 square pyramids that share corners with two equivalent SLu2Mg3 square pyramids and edges with five SLu3Mg2 square pyramids.