Na2Sr3P4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to one P(1), one P(2), one P(4), and two equivalent P(3) atoms. In the second Na site, Na(2) is bonded to one P(2), one P(3), and two equivalent P(1) atoms to form distorted corner-sharing NaP4 tetrahedra. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one P(2), one P(3), two equivalent P(1), and two equivalent P(4) atoms. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one P(1), one P(2), two equivalent P(3), and two equivalent P(4) atoms. In the third Sr site, Sr(3) is bonded in a 5-coordinate geometry to one P(3), two equivalent P(1), and two equivalent P(2) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded in a 8-coordinate geometry to one Na(1), two equivalent Na(2), one Sr(2), two equivalent Sr(1), and two equivalent Sr(3) atoms. In the second P site, P(2) is bonded to one Na(1), one Na(2), one Sr(1), one Sr(2), two equivalent Sr(3), and one P(4) atom to form distorted edge-sharing PNa2Sr4P pentagonal bipyramids. In the third P site, P(3) is bonded in a 8-coordinate geometry to one Na(2), two equivalent Na(1), one Sr(1), one Sr(3), two equivalent Sr(2), and one P(4) atom. In the fourth P site, P(4) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Sr(1), two equivalent Sr(2), one P(2), and one P(3) atom.
Na2Sr3P4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to one P(1), one P(2), one P(4), and two equivalent P(3) atoms. The Na(1)-P(1) bond length is 3.00 Å. The Na(1)-P(2) bond length is 2.92 Å. The Na(1)-P(4) bond length is 3.28 Å. There is one shorter (3.07 Å) and one longer (3.09 Å) Na(1)-P(3) bond length. In the second Na site, Na(2) is bonded to one P(2), one P(3), and two equivalent P(1) atoms to form distorted corner-sharing NaP4 tetrahedra. The Na(2)-P(2) bond length is 3.07 Å. The Na(2)-P(3) bond length is 3.02 Å. There is one shorter (2.81 Å) and one longer (2.89 Å) Na(2)-P(1) bond length. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one P(2), one P(3), two equivalent P(1), and two equivalent P(4) atoms. The Sr(1)-P(2) bond length is 3.08 Å. The Sr(1)-P(3) bond length is 3.43 Å. There is one shorter (3.00 Å) and one longer (3.34 Å) Sr(1)-P(1) bond length. There is one shorter (3.15 Å) and one longer (3.35 Å) Sr(1)-P(4) bond length. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one P(1), one P(2), two equivalent P(3), and two equivalent P(4) atoms. The Sr(2)-P(1) bond length is 3.04 Å. The Sr(2)-P(2) bond length is 3.00 Å. There is one shorter (3.08 Å) and one longer (3.13 Å) Sr(2)-P(3) bond length. There is one shorter (2.93 Å) and one longer (3.19 Å) Sr(2)-P(4) bond length. In the third Sr site, Sr(3) is bonded in a 5-coordinate geometry to one P(3), two equivalent P(1), and two equivalent P(2) atoms. The Sr(3)-P(3) bond length is 3.16 Å. There is one shorter (3.25 Å) and one longer (3.52 Å) Sr(3)-P(1) bond length. There is one shorter (3.00 Å) and one longer (3.26 Å) Sr(3)-P(2) bond length. There are four inequivalent P sites. In the first P site, P(1) is bonded in a 8-coordinate geometry to one Na(1), two equivalent Na(2), one Sr(2), two equivalent Sr(1), and two equivalent Sr(3) atoms. In the second P site, P(2) is bonded to one Na(1), one Na(2), one Sr(1), one Sr(2), two equivalent Sr(3), and one P(4) atom to form distorted edge-sharing PNa2Sr4P pentagonal bipyramids. The P(2)-P(4) bond length is 2.31 Å. In the third P site, P(3) is bonded in a 8-coordinate geometry to one Na(2), two equivalent Na(1), one Sr(1), one Sr(3), two equivalent Sr(2), and one P(4) atom. The P(3)-P(4) bond length is 2.24 Å. In the fourth P site, P(4) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Sr(1), two equivalent Sr(2), one P(2), and one P(3) atom.