Materials Data on Mn2CrGa3S8 by Materials Project

Abstract

CrMn2Ga3S8 crystallizes in the monoclinic Cm space group. The structure is two-dimensional and consists of two CrMn2Ga3S8 sheets oriented in the (1, 0, 0) direction. Cr3+ is bonded to four S2- atoms to form CrS4 tetrahedra that share corners with three GaS6 octahedra, corners with two equivalent CrS4 tetrahedra, and corners with four equivalent GaS4 tetrahedra. The corner-sharing octahedra tilt angles range from 57–58°. There are a spread of Cr–S bond distances ranging from 2.31–2.39 Å. There are two inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to four S2- atoms to form MnS4 tetrahedra that share corners with three GaS6 octahedra and corners with six MnS4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. There are three shorter (2.32 Å) and one longer (2.41 Å) Mn–S bond lengths. In the second Mn2+ site, Mn2+ is bonded to four S2- atoms to form MnS4 tetrahedra that share corners with three GaS6 octahedra and corners with six MnS4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. There are three shorter (2.32 Å) and one longer (2.40 Å) Mn–S bond lengths. There are three inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to six S2- atoms to form GaS6 octahedra that share a cornercorner with one GaS4 tetrahedra, corners with two equivalent CrS4 tetrahedra, corners with three MnS4 tetrahedra, and edges with six GaS6 octahedra. There are a spread of Ga–S bond distances ranging from 2.50–2.56 Å. In the second Ga3+ site, Ga3+ is bonded to six S2- atoms to form GaS6 octahedra that share a cornercorner with one CrS4 tetrahedra, corners with two equivalent GaS4 tetrahedra, corners with three MnS4 tetrahedra, and edges with six GaS6 octahedra. There are a spread of Ga–S bond distances ranging from 2.48–2.54 Å. In the third Ga3+ site, Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three GaS6 octahedra, corners with two equivalent GaS4 tetrahedra, and corners with four equivalent CrS4 tetrahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of Ga–S bond distances ranging from 2.30–2.35 Å. There are eight inequivalent S2- sites. In the first S2- site, S2- is bonded in a trigonal non-coplanar geometry to one Cr3+ and two equivalent Ga3+ atoms. In the second S2- site, S2- is bonded in a trigonal non-coplanar geometry to two equivalent Cr3+ and one Ga3+ atom. In the third S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Mn2+ atoms. In the fourth S2- site, S2- is bonded in a trigonal non-coplanar geometry to three Mn2+ atoms. In the fifth S2- site, S2- is bonded to one Cr3+ and three Ga3+ atoms to form distorted SCrGa3 trigonal pyramids that share corners with nine SCrGa3 trigonal pyramids and edges with three SMnGa3 trigonal pyramids. In the sixth S2- site, S2- is bonded to four Ga3+ atoms to form distorted SGa4 trigonal pyramids that share corners with nine SCrGa3 trigonal pyramids and edges with three SMnGa3 trigonal pyramids. In the seventh S2- site, S2- is bonded to one Mn2+ and three Ga3+ atoms to form distorted SMnGa3 trigonal pyramids that share corners with nine SGa4 trigonal pyramids and edges with three SCrGa3 trigonal pyramids. In the eighth S2- site, S2- is bonded to one Mn2+ and three Ga3+ atoms to form a mixture of distorted corner and edge-sharing SMnGa3 trigonal pyramids.