Na3Sr3AlP4 crystallizes in the hexagonal P6_3mc space group. Na(1) is bonded in a 4-coordinate geometry to one P(1) and three equivalent P(2) atoms. Sr(1) is bonded in a 7-coordinate geometry to one Al(1), two equivalent P(1), and four equivalent P(2) atoms. Al(1) is bonded in a distorted tetrahedral geometry to three equivalent Sr(1), one P(1), and three equivalent P(2) atoms. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 10-coordinate geometry to three equivalent Na(1), six equivalent Sr(1), and one Al(1) atom. In the second P site, P(2) is bonded in a 8-coordinate geometry to three equivalent Na(1), four equivalent Sr(1), and one Al(1) atom.
Na3Sr3AlP4 crystallizes in the hexagonal P6_3mc space group. Na(1) is bonded in a 4-coordinate geometry to one P(1) and three equivalent P(2) atoms. The Na(1)-P(1) bond length is 3.24 Å. There are two shorter (2.91 Å) and one longer (3.04 Å) Na(1)-P(2) bond length. Sr(1) is bonded in a 7-coordinate geometry to one Al(1), two equivalent P(1), and four equivalent P(2) atoms. The Sr(1)-Al(1) bond length is 3.25 Å. There is one shorter (3.16 Å) and one longer (3.49 Å) Sr(1)-P(1) bond length. There are two shorter (3.11 Å) and two longer (3.24 Å) Sr(1)-P(2) bond lengths. Al(1) is bonded in a distorted tetrahedral geometry to three equivalent Sr(1), one P(1), and three equivalent P(2) atoms. The Al(1)-P(1) bond length is 2.49 Å. All Al(1)-P(2) bond lengths are 2.42 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded in a 10-coordinate geometry to three equivalent Na(1), six equivalent Sr(1), and one Al(1) atom. In the second P site, P(2) is bonded in a 8-coordinate geometry to three equivalent Na(1), four equivalent Sr(1), and one Al(1) atom.