Materials Data on Al4InCuS8 by Materials Project

CuInAl4S8 is Spinel-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with three equivalent InS6 octahedra and corners with nine equivalent AlS6 octahedra. The corner-sharing octahedra tilt angles range from 52–60°. There are three shorter (2.30 Å) and one longer (2.33 Å) Cu–S bond lengths. In3+ is bonded to six S2- atoms to form InS6 octahedra that share corners with three equivalent CuS4 tetrahedra, corners with three equivalent AlS4 tetrahedra, and edges with six equivalent AlS6 octahedra. There are three shorter (2.54 Å) and three longer (2.63 Å) In–S bond lengths. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four S2- atoms to form AlS4 tetrahedra that share corners with three equivalent InS6 octahedra and corners with nine equivalent AlS6 octahedra. The corner-sharing octahedra tilt angles range from 57–63°. There are three shorter (2.32 Å) and one longer (2.36 Å) Al–S bond lengths. In the second Al3+ site, Al3+ is bonded to six S2- atoms to form AlS6 octahedra that share corners with three equivalent CuS4 tetrahedra, corners with three equivalent AlS4 tetrahedra, edges with two equivalent InS6 octahedra, and edges with four equivalent AlS6 octahedra. There are a spread of Al–S bond distances ranging from 2.38–2.55 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to one Cu1+, one In3+, and two equivalent Al3+ atoms. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to one Cu1+ and three equivalent Al3+ atoms. In the third S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to one In3+ and three Al3+ atoms. In the fourth S2- site, S2- is bonded in a distorted trigonal pyramidal geometry to four Al3+ atoms.