SrAl4O7 crystallizes in the orthorhombic Cmme space group. Sr(1) is bonded in a distorted q6 geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form AlO4 tetrahedra that share  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Al(1)O4 tetrahedra, corners with two equivalent Al(2)O4 tetrahedra, and  an edgeedge with one Al(3)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. In the second Al site, Al(2) is bonded to four equivalent O(1) atoms to form AlO4 tetrahedra that share corners with four equivalent Al(3)O6 octahedra and corners with four equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. In the third Al site, Al(3) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form a mixture of corner and edge-sharing AlO6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Al(1), one Al(2), and one Al(3) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Sr(1), one Al(1), and one Al(3) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Sr(1) and two equivalent Al(1) atoms.
SrAl4O7 crystallizes in the orthorhombic Cmme space group. Sr(1) is bonded in a distorted q6 geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. Both Sr(1)-O(3) bond lengths are 2.79 Å. All Sr(1)-O(1) bond lengths are 2.94 Å. All Sr(1)-O(2) bond lengths are 3.09 Å. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form AlO4 tetrahedra that share  a cornercorner with one Al(3)O6 octahedra,  a cornercorner with one Al(1)O4 tetrahedra, corners with two equivalent Al(2)O4 tetrahedra, and  an edgeedge with one Al(3)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. The Al(1)-O(2) bond length is 1.73 Å. The Al(1)-O(3) bond length is 1.72 Å. Both Al(1)-O(1) bond lengths are 1.78 Å. In the second Al site, Al(2) is bonded to four equivalent O(1) atoms to form AlO4 tetrahedra that share corners with four equivalent Al(3)O6 octahedra and corners with four equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. All Al(2)-O(1) bond lengths are 1.77 Å. In the third Al site, Al(3) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form a mixture of corner and edge-sharing AlO6 octahedra. Both Al(3)-O(2) bond lengths are 1.86 Å. All Al(3)-O(1) bond lengths are 2.08 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Al(1), one Al(2), and one Al(3) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Sr(1), one Al(1), and one Al(3) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Sr(1) and two equivalent Al(1) atoms.