Materials Data on La2MgS4 by Materials Project

MgLa2S4 is Spinel-like structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Mg2+ is bonded to four S2- atoms to form MgS4 tetrahedra that share corners with six LaS6 octahedra and edges with three LaS6 octahedra. The corner-sharing octahedra tilt angles range from 60–62°. There are a spread of Mg–S bond distances ranging from 2.42–2.49 Å. There are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to six S2- atoms to form LaS6 octahedra that share corners with four equivalent LaS6 octahedra, corners with two equivalent MgS4 tetrahedra, edges with four LaS6 octahedra, and edges with two equivalent MgS4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–58°. There are four shorter (2.87 Å) and two longer (2.92 Å) La–S bond lengths. In the second La3+ site, La3+ is bonded to six S2- atoms to form LaS6 octahedra that share corners with eight LaS6 octahedra, corners with four equivalent MgS4 tetrahedra, edges with two equivalent LaS6 octahedra, and an edgeedge with one MgS4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–58°. There are a spread of La–S bond distances ranging from 2.86–2.97 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three La3+ atoms. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three La3+ atoms. In the third S2- site, S2- is bonded to one Mg2+ and three La3+ atoms to form distorted corner-sharing SLa3Mg tetrahedra.