DOE OSTI2020
Al5(BiSe4)3 crystallizes in the tetragonal P-42c space group. The structure is three-dimensional. there are six inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four Se2- atoms to form edge-sharing AlSe4 tetrahedra. There are two shorter (2.38 Å) and two longer (2.45 Å) Al–Se bond lengths. In the second Al3+ site, Al3+ is bonded to four equivalent Se2- atoms to form edge-sharing AlSe4 tetrahedra. All Al–Se bond lengths are 2.43 Å. In the third Al3+ site, Al3+ is bonded to four Se2- atoms to form edge-sharing AlSe4 tetrahedra. There are two shorter (2.42 Å) and two longer (2.43 Å) Al–Se bond lengths. In the fourth Al3+ site, Al3+ is bonded to four Se2- atoms to form edge-sharing AlSe4 tetrahedra. There are two shorter (2.38 Å) and two longer (2.46 Å) Al–Se bond lengths. In the fifth Al3+ site, Al3+ is bonded to four equivalent Se2- atoms to form edge-sharing AlSe4 tetrahedra. All Al–Se bond lengths are 2.43 Å. In the sixth Al3+ site, Al3+ is bonded to four Se2- atoms to form edge-sharing AlSe4 tetrahedra. All Al–Se bond lengths are 2.43 Å. There are three inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a rectangular see-saw-like geometry to four Se2- atoms. All Bi–Se bond lengths are 2.98 Å. In the second Bi3+ site, Bi3+ is bonded in a square co-planar geometry to four Se2- atoms. There are two shorter (2.92 Å) and two longer (2.98 Å) Bi–Se bond lengths. In the third Bi3+ site, Bi3+ is bonded in a square co-planar geometry to four Se2- atoms. There are two shorter (2.94 Å) and two longer (2.98 Å) Bi–Se bond lengths. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to two Al3+ and one Bi3+ atom. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to two Al3+ and one Bi3+ atom. In the third Se2- site, Se2- is bonded in a distorted water-like geometry to one Al3+ and one Bi3+ atom. In the fourth Se2- site, Se2- is bonded in a 3-coordinate geometry to two Al3+ and one Bi3+ atom. In the fifth Se2- site, Se2- is bonded in a 3-coordinate geometry to two Al3+ and one Bi3+ atom. In the sixth Se2- site, Se2- is bonded in a distorted water-like geometry to one Al3+ and one Bi3+ atom.