Materials Data on Al(CuSe2)3 by Materials Project
Al(CuSe2)3 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. there are two inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four Se1- atoms to form CuSe4 tetrahedra that share corners with two equivalent AlSe4 tetrahedra and corners with four CuSe4 tetrahedra. There are two shorter (2.32 Å) and two longer (2.39 Å) Cu–Se bond lengths. In the second Cu1+ site, Cu1+ is bonded to four equivalent Se1- atoms to form CuSe4 tetrahedra that share corners with four equivalent CuSe4 tetrahedra and corners with four equivalent AlSe4 tetrahedra. All Cu–Se bond lengths are 2.39 Å. Al3+ is bonded to four equivalent Se1- atoms to form AlSe4 tetrahedra that share corners with eight CuSe4 tetrahedra. All Al–Se bond lengths are 2.41 Å. There are two inequivalent Se1- sites. In the first Se1- site, Se1- is bonded in a water-like geometry to two equivalent Cu1+ atoms. In the second Se1- site, Se1- is bonded in a distorted trigonal non-coplanar geometry to two Cu1+ and one Al3+ atom.