SrAl2Si2O8 crystallizes in the monoclinic C2/c space group. Sr(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(6), one O(7), and one O(8) atom to form AlO4 tetrahedra that share corners with three equivalent Si(1)O4 tetrahedra. In the second Al site, Al(2) is bonded in a trigonal planar geometry to one O(1), one O(3), and one O(5) atom. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(5), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with three equivalent Al(1)O4 tetrahedra. In the second Si site, Si(2) is bonded in a trigonal non-coplanar geometry to one O(1), one O(3), and one O(4) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Al(2), and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Al(2) and one Si(2) atom. In the fourth O site, O(4) is bonded in a linear geometry to one Sr(1) and one Si(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Sr(1), one Al(2), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Sr(1) and one Al(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Al(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Al(1), and one Si(1) atom.
SrAl2Si2O8 crystallizes in the monoclinic C2/c space group. Sr(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. The Sr(1)-O(1) bond length is 2.69 Å. The Sr(1)-O(4) bond length is 2.28 Å. The Sr(1)-O(5) bond length is 2.84 Å. The Sr(1)-O(6) bond length is 2.81 Å. The Sr(1)-O(7) bond length is 2.64 Å. The Sr(1)-O(8) bond length is 2.68 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(6), one O(7), and one O(8) atom to form AlO4 tetrahedra that share corners with three equivalent Si(1)O4 tetrahedra. The Al(1)-O(2) bond length is 1.73 Å. The Al(1)-O(6) bond length is 1.81 Å. The Al(1)-O(7) bond length is 1.78 Å. The Al(1)-O(8) bond length is 1.77 Å. In the second Al site, Al(2) is bonded in a trigonal planar geometry to one O(1), one O(3), and one O(5) atom. The Al(2)-O(1) bond length is 1.72 Å. The Al(2)-O(3) bond length is 1.69 Å. The Al(2)-O(5) bond length is 1.72 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(5), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with three equivalent Al(1)O4 tetrahedra. The Si(1)-O(2) bond length is 1.62 Å. The Si(1)-O(5) bond length is 1.65 Å. The Si(1)-O(7) bond length is 1.66 Å. The Si(1)-O(8) bond length is 1.64 Å. In the second Si site, Si(2) is bonded in a trigonal non-coplanar geometry to one O(1), one O(3), and one O(4) atom. The Si(2)-O(1) bond length is 1.69 Å. The Si(2)-O(3) bond length is 1.66 Å. The Si(2)-O(4) bond length is 1.58 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Al(2), and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Al(2) and one Si(2) atom. In the fourth O site, O(4) is bonded in a linear geometry to one Sr(1) and one Si(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Sr(1), one Al(2), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Sr(1) and one Al(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Al(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Al(1), and one Si(1) atom.