NaAl(SO4)2 crystallizes in the orthorhombic Pnma space group. Na(1) is bonded in a 6-coordinate geometry to one O(1), two equivalent O(4), and three equivalent O(2) atoms. Al(1) is bonded to one O(3), one O(5), two equivalent O(4), and two equivalent O(6) atoms to form AlO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(1), one O(5), and two equivalent O(6) atoms to form SO4 tetrahedra that share corners with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-37°. In the second S site, S(2) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form SO4 tetrahedra that share corners with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-34°. There are six inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Al(1) and one S(1) atom. In the second O site, O(6) is bonded in a bent 150 degrees geometry to one Al(1) and one S(1) atom. In the third O site, O(1) is bonded in a distorted linear geometry to one Na(1) and one S(1) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Na(1) and one S(2) atom. In the fifth O site, O(3) is bonded in a linear geometry to one Al(1) and one S(2) atom. In the sixth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Al(1), and one S(2) atom.
NaAl(SO4)2 crystallizes in the orthorhombic Pnma space group. Na(1) is bonded in a 6-coordinate geometry to one O(1), two equivalent O(4), and three equivalent O(2) atoms. The Na(1)-O(1) bond length is 2.37 Å. Both Na(1)-O(4) bond lengths are 2.57 Å. There is one shorter (2.39 Å) and two longer (2.64 Å) Na(1)-O(2) bond lengths. Al(1) is bonded to one O(3), one O(5), two equivalent O(4), and two equivalent O(6) atoms to form AlO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. The Al(1)-O(3) bond length is 1.88 Å. The Al(1)-O(5) bond length is 1.91 Å. Both Al(1)-O(4) bond lengths are 1.92 Å. Both Al(1)-O(6) bond lengths are 1.90 Å. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(1), one O(5), and two equivalent O(6) atoms to form SO4 tetrahedra that share corners with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-37°. The S(1)-O(1) bond length is 1.44 Å. The S(1)-O(5) bond length is 1.50 Å. Both S(1)-O(6) bond lengths are 1.50 Å. In the second S site, S(2) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form SO4 tetrahedra that share corners with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-34°. The S(2)-O(2) bond length is 1.46 Å. The S(2)-O(3) bond length is 1.47 Å. Both S(2)-O(4) bond lengths are 1.49 Å. There are six inequivalent O sites. In the first O site, O(5) is bonded in a bent 150 degrees geometry to one Al(1) and one S(1) atom. In the second O site, O(6) is bonded in a bent 150 degrees geometry to one Al(1) and one S(1) atom. In the third O site, O(1) is bonded in a distorted linear geometry to one Na(1) and one S(1) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Na(1) and one S(2) atom. In the fifth O site, O(3) is bonded in a linear geometry to one Al(1) and one S(2) atom. In the sixth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Al(1), and one S(2) atom.