Materials Data on Mg(FeS2)2 by Materials Project
Mg(FeS2)2 is Spinel structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four S2- atoms to form MgS4 tetrahedra that share corners with twelve FeS6 octahedra. The corner-sharing octahedra tilt angles range from 60–61°. There are two shorter (2.42 Å) and two longer (2.43 Å) Mg–S bond lengths. In the second Mg2+ site, Mg2+ is bonded to four S2- atoms to form MgS4 tetrahedra that share corners with twelve FeS6 octahedra. The corner-sharing octahedra tilt angles range from 60–61°. There are two shorter (2.42 Å) and two longer (2.43 Å) Mg–S bond lengths. There are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with six MgS4 tetrahedra and edges with six FeS6 octahedra. All Fe–S bond lengths are 2.31 Å. In the second Fe3+ site, Fe3+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with six MgS4 tetrahedra and edges with six FeS6 octahedra. There are four shorter (2.30 Å) and two longer (2.31 Å) Fe–S bond lengths. In the third Fe3+ site, Fe3+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with six MgS4 tetrahedra and edges with six FeS6 octahedra. All Fe–S bond lengths are 2.31 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded to one Mg2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing SMgFe3 tetrahedra. In the second S2- site, S2- is bonded to one Mg2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing SMgFe3 tetrahedra. In the third S2- site, S2- is bonded to one Mg2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing SMgFe3 tetrahedra. In the fourth S2- site, S2- is bonded to one Mg2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing SMgFe3 tetrahedra. In the fifth S2- site, S2- is bonded to one Mg2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing SMgFe3 tetrahedra. In the sixth S2- site, S2- is bonded to one Mg2+ and three Fe3+ atoms to form a mixture of distorted edge and corner-sharing SMgFe3 tetrahedra.