(Al4As3O16)2(O2)7 crystallizes in the cubic P-43m space group. The structure consists of seven water atoms inside a Al4As3O16 framework. In the Al4As3O16 framework, Al(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form AlO6 octahedra that share corners with three equivalent As(1)O4 tetrahedra and edges with three equivalent Al(1)O6 octahedra. As(1) is bonded to four equivalent O(1) atoms to form AsO4 tetrahedra that share corners with four equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. There are two inequivalent O sites. In the first O site, O(2) is bonded in a trigonal non-coplanar geometry to three equivalent Al(1) atoms. In the second O site, O(1) is bonded in a bent 120 degrees geometry to one Al(1) and one As(1) atom.
(Al4As3O16)2(O2)7 crystallizes in the cubic P-43m space group. The structure consists of seven water atoms inside a Al4As3O16 framework. In the Al4As3O16 framework, Al(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form AlO6 octahedra that share corners with three equivalent As(1)O4 tetrahedra and edges with three equivalent Al(1)O6 octahedra. All Al(1)-O(1) bond lengths are 1.85 Å. All Al(1)-O(2) bond lengths are 1.96 Å. As(1) is bonded to four equivalent O(1) atoms to form AsO4 tetrahedra that share corners with four equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. All As(1)-O(1) bond lengths are 1.71 Å. There are two inequivalent O sites. In the first O site, O(2) is bonded in a trigonal non-coplanar geometry to three equivalent Al(1) atoms. In the second O site, O(1) is bonded in a bent 120 degrees geometry to one Al(1) and one As(1) atom.