Materials Data on Mg(TiS2)8 by Materials Project

Abstract

Mg(TiS2)8 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. Mg2+ is bonded to six S2- atoms to form MgS6 octahedra that share corners with six TiS6 octahedra and edges with six TiS6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are two shorter (2.52 Å) and four longer (2.53 Å) Mg–S bond lengths. There are four inequivalent Ti+3.75+ sites. In the first Ti+3.75+ site, Ti+3.75+ is bonded to six S2- atoms to form TiS6 octahedra that share an edgeedge with one MgS6 octahedra and edges with six TiS6 octahedra. There are a spread of Ti–S bond distances ranging from 2.39–2.51 Å. In the second Ti+3.75+ site, Ti+3.75+ is bonded to six S2- atoms to form TiS6 octahedra that share corners with two equivalent MgS6 octahedra and edges with six TiS6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Ti–S bond distances ranging from 2.38–2.50 Å. In the third Ti+3.75+ site, Ti+3.75+ is bonded to six S2- atoms to form TiS6 octahedra that share edges with two equivalent MgS6 octahedra and edges with six TiS6 octahedra. There are two shorter (2.45 Å) and four longer (2.46 Å) Ti–S bond lengths. In the fourth Ti+3.75+ site, Ti+3.75+ is bonded to six S2- atoms to form TiS6 octahedra that share corners with two equivalent MgS6 octahedra and edges with six TiS6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are two shorter (2.43 Å) and four longer (2.44 Å) Ti–S bond lengths. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three Ti+3.75+ atoms. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Ti+3.75+ atoms. In the third S2- site, S2- is bonded in a distorted T-shaped geometry to three Ti+3.75+ atoms. In the fourth S2- site, S2- is bonded in a distorted T-shaped geometry to three Ti+3.75+ atoms. In the fifth S2- site, S2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Ti+3.75+ atoms. In the sixth S2- site, S2- is bonded in a distorted T-shaped geometry to three Ti+3.75+ atoms.