SrMgSn(PO4)2 crystallizes in the triclinic P-1 space group. Sr(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(8), two equivalent O(1), and two equivalent O(6) atoms. Mg(1) is bonded to one O(2), one O(4), one O(5), and one O(7) atom to form MgO4 tetrahedra that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(2)O4 tetrahedra. Sn(1) is bonded in a 5-coordinate geometry to one O(3), one O(4), one O(5), one O(7), and one O(8) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Sr(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Sr(1), one Mg(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(1), one Sn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Sr(1), one Mg(1), one Sn(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Mg(1), one Sn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to two equivalent Sr(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Mg(1), one Sn(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sn(1), and one P(2) atom.
SrMgSn(PO4)2 crystallizes in the triclinic P-1 space group. Sr(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(8), two equivalent O(1), and two equivalent O(6) atoms. The Sr(1)-O(2) bond length is 3.00 Å. The Sr(1)-O(3) bond length is 2.66 Å. The Sr(1)-O(4) bond length is 3.06 Å. The Sr(1)-O(8) bond length is 2.66 Å. There is one shorter (2.57 Å) and one longer (2.67 Å) Sr(1)-O(1) bond length. There is one shorter (2.49 Å) and one longer (3.06 Å) Sr(1)-O(6) bond length. Mg(1) is bonded to one O(2), one O(4), one O(5), and one O(7) atom to form MgO4 tetrahedra that share corners with two equivalent P(1)O4 tetrahedra and corners with two equivalent P(2)O4 tetrahedra. The Mg(1)-O(2) bond length is 1.97 Å. The Mg(1)-O(4) bond length is 2.03 Å. The Mg(1)-O(5) bond length is 2.05 Å. The Mg(1)-O(7) bond length is 1.98 Å. Sn(1) is bonded in a 5-coordinate geometry to one O(3), one O(4), one O(5), one O(7), and one O(8) atom. The Sn(1)-O(3) bond length is 2.21 Å. The Sn(1)-O(4) bond length is 2.45 Å. The Sn(1)-O(5) bond length is 2.63 Å. The Sn(1)-O(7) bond length is 2.69 Å. The Sn(1)-O(8) bond length is 2.31 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra. The P(1)-O(1) bond length is 1.53 Å. The P(1)-O(2) bond length is 1.55 Å. The P(1)-O(3) bond length is 1.57 Å. The P(1)-O(7) bond length is 1.57 Å. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra. The P(2)-O(4) bond length is 1.59 Å. The P(2)-O(5) bond length is 1.58 Å. The P(2)-O(6) bond length is 1.51 Å. The P(2)-O(8) bond length is 1.56 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Sr(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Sr(1), one Mg(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(1), one Sn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Sr(1), one Mg(1), one Sn(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Mg(1), one Sn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to two equivalent Sr(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Mg(1), one Sn(1), and one P(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sn(1), and one P(2) atom.