Sr3P4 crystallizes in the triclinic P1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one P(1), one P(2), one P(3), one P(4), one P(5), one P(8), and two equivalent P(6) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one P(1), one P(2), one P(3), one P(4), one P(6), one P(7), and two equivalent P(5) atoms. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one P(1), one P(2), one P(3), one P(4), one P(5), one P(8), and two equivalent P(7) atoms. In the fourth Sr site, Sr(4) is bonded in a 8-coordinate geometry to one P(1), one P(2), one P(3), one P(4), one P(6), one P(7), and two equivalent P(8) atoms. In the fifth Sr site, Sr(5) is bonded to one P(5), one P(6), one P(7), one P(8), two equivalent P(1), and two equivalent P(2) atoms to form SrP8 hexagonal bipyramids that share corners with four equivalent Sr(6)P8 hexagonal bipyramids, corners with two equivalent P(6)Sr6P pentagonal bipyramids, and edges with two equivalent Sr(5)P8 hexagonal bipyramids. In the sixth Sr site, Sr(6) is bonded to one P(5), one P(6), one P(7), one P(8), two equivalent P(3), and two equivalent P(4) atoms to form SrP8 hexagonal bipyramids that share corners with four equivalent Sr(5)P8 hexagonal bipyramids, corners with two equivalent P(7)Sr6P pentagonal bipyramids, and edges with two equivalent Sr(6)P8 hexagonal bipyramids. There are eight inequivalent P sites. In the first P site, P(1) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(5), one P(2), and one P(6) atom. In the second P site, P(2) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(5), one P(1), and one P(5) atom. In the third P site, P(3) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(6), one P(4), and one P(7) atom. In the fourth P site, P(4) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(6), one P(3), and one P(8) atom. In the fifth P site, P(5) is bonded in a 7-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Sr(6), two equivalent Sr(2), and one P(2) atom. In the sixth P site, P(6) is bonded to one Sr(2), one Sr(4), one Sr(5), one Sr(6), two equivalent Sr(1), and one P(1) atom to form distorted PSr6P pentagonal bipyramids that share corners with two equivalent Sr(5)P8 hexagonal bipyramids, corners with two equivalent P(6)Sr6P pentagonal bipyramids, and edges with two equivalent P(7)Sr6P pentagonal bipyramids. In the seventh P site, P(7) is bonded to one Sr(2), one Sr(4), one Sr(5), one Sr(6), two equivalent Sr(3), and one P(3) atom to form distorted PSr6P pentagonal bipyramids that share corners with two equivalent Sr(6)P8 hexagonal bipyramids, corners with two equivalent P(7)Sr6P pentagonal bipyramids, and edges with two equivalent P(6)Sr6P pentagonal bipyramids. In the eighth P site, P(8) is bonded in a 7-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Sr(6), two equivalent Sr(4), and one P(4) atom.
Sr3P4 crystallizes in the triclinic P1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one P(1), one P(2), one P(3), one P(4), one P(5), one P(8), and two equivalent P(6) atoms. The Sr(1)-P(1) bond length is 3.07 Å. The Sr(1)-P(2) bond length is 3.30 Å. The Sr(1)-P(3) bond length is 3.17 Å. The Sr(1)-P(4) bond length is 3.12 Å. The Sr(1)-P(5) bond length is 3.13 Å. The Sr(1)-P(8) bond length is 3.13 Å. There is one shorter (3.10 Å) and one longer (3.32 Å) Sr(1)-P(6) bond length. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one P(1), one P(2), one P(3), one P(4), one P(6), one P(7), and two equivalent P(5) atoms. The Sr(2)-P(1) bond length is 3.18 Å. The Sr(2)-P(2) bond length is 3.16 Å. The Sr(2)-P(3) bond length is 3.15 Å. The Sr(2)-P(4) bond length is 3.20 Å. The Sr(2)-P(6) bond length is 3.06 Å. The Sr(2)-P(7) bond length is 3.17 Å. There is one shorter (3.14 Å) and one longer (3.26 Å) Sr(2)-P(5) bond length. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one P(1), one P(2), one P(3), one P(4), one P(5), one P(8), and two equivalent P(7) atoms. The Sr(3)-P(1) bond length is 3.18 Å. The Sr(3)-P(2) bond length is 3.13 Å. The Sr(3)-P(3) bond length is 3.13 Å. The Sr(3)-P(4) bond length is 3.28 Å. The Sr(3)-P(5) bond length is 3.11 Å. The Sr(3)-P(8) bond length is 3.12 Å. There is one shorter (3.13 Å) and one longer (3.28 Å) Sr(3)-P(7) bond length. In the fourth Sr site, Sr(4) is bonded in a 8-coordinate geometry to one P(1), one P(2), one P(3), one P(4), one P(6), one P(7), and two equivalent P(8) atoms. The Sr(4)-P(1) bond length is 3.22 Å. The Sr(4)-P(2) bond length is 3.17 Å. The Sr(4)-P(3) bond length is 3.23 Å. The Sr(4)-P(4) bond length is 3.13 Å. The Sr(4)-P(6) bond length is 3.14 Å. The Sr(4)-P(7) bond length is 3.04 Å. There is one shorter (3.13 Å) and one longer (3.25 Å) Sr(4)-P(8) bond length. In the fifth Sr site, Sr(5) is bonded to one P(5), one P(6), one P(7), one P(8), two equivalent P(1), and two equivalent P(2) atoms to form SrP8 hexagonal bipyramids that share corners with four equivalent Sr(6)P8 hexagonal bipyramids, corners with two equivalent P(6)Sr6P pentagonal bipyramids, and edges with two equivalent Sr(5)P8 hexagonal bipyramids. The Sr(5)-P(5) bond length is 3.04 Å. The Sr(5)-P(6) bond length is 3.00 Å. The Sr(5)-P(7) bond length is 3.36 Å. The Sr(5)-P(8) bond length is 3.20 Å. There is one shorter (3.14 Å) and one longer (3.22 Å) Sr(5)-P(1) bond length. There is one shorter (3.09 Å) and one longer (3.18 Å) Sr(5)-P(2) bond length. In the sixth Sr site, Sr(6) is bonded to one P(5), one P(6), one P(7), one P(8), two equivalent P(3), and two equivalent P(4) atoms to form SrP8 hexagonal bipyramids that share corners with four equivalent Sr(5)P8 hexagonal bipyramids, corners with two equivalent P(7)Sr6P pentagonal bipyramids, and edges with two equivalent Sr(6)P8 hexagonal bipyramids. The Sr(6)-P(5) bond length is 3.25 Å. The Sr(6)-P(6) bond length is 3.36 Å. The Sr(6)-P(7) bond length is 3.03 Å. The Sr(6)-P(8) bond length is 3.09 Å. There is one shorter (3.15 Å) and one longer (3.17 Å) Sr(6)-P(3) bond length. There is one shorter (3.12 Å) and one longer (3.16 Å) Sr(6)-P(4) bond length. There are eight inequivalent P sites. In the first P site, P(1) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(5), one P(2), and one P(6) atom. The P(1)-P(2) bond length is 2.32 Å. The P(1)-P(6) bond length is 2.17 Å. In the second P site, P(2) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(5), one P(1), and one P(5) atom. The P(2)-P(5) bond length is 2.30 Å. In the third P site, P(3) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(6), one P(4), and one P(7) atom. The P(3)-P(4) bond length is 2.27 Å. The P(3)-P(7) bond length is 2.23 Å. In the fourth P site, P(4) is bonded in a 8-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Sr(4), two equivalent Sr(6), one P(3), and one P(8) atom. The P(4)-P(8) bond length is 2.29 Å. In the fifth P site, P(5) is bonded in a 7-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Sr(6), two equivalent Sr(2), and one P(2) atom. In the sixth P site, P(6) is bonded to one Sr(2), one Sr(4), one Sr(5), one Sr(6), two equivalent Sr(1), and one P(1) atom to form distorted PSr6P pentagonal bipyramids that share corners with two equivalent Sr(5)P8 hexagonal bipyramids, corners with two equivalent P(6)Sr6P pentagonal bipyramids, and edges with two equivalent P(7)Sr6P pentagonal bipyramids. In the seventh P site, P(7) is bonded to one Sr(2), one Sr(4), one Sr(5), one Sr(6), two equivalent Sr(3), and one P(3) atom to form distorted PSr6P pentagonal bipyramids that share corners with two equivalent Sr(6)P8 hexagonal bipyramids, corners with two equivalent P(7)Sr6P pentagonal bipyramids, and edges with two equivalent P(6)Sr6P pentagonal bipyramids. In the eighth P site, P(8) is bonded in a 7-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Sr(6), two equivalent Sr(4), and one P(4) atom.