SrIn2(PO4)4 crystallizes in the orthorhombic C222_1 space group. Sr(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms. There are two inequivalent In sites. In the first In site, In(1) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms to form InO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and corners with four equivalent P(2)O4 tetrahedra. In the second In site, In(2) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms to form InO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. 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(4) atom to form PO4 tetrahedra that share  a cornercorner with one In(1)O6 octahedra and corners with two equivalent In(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 37-47°. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one In(2)O6 octahedra and corners with two equivalent In(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-43°. There are eight inequivalent O sites. In the first O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1), one In(1), and one P(1) atom. In the second O site, O(3) is bonded in a distorted bent 150 degrees geometry to one In(2) and one P(1) atom. In the third O site, O(4) is bonded in a distorted trigonal planar geometry to one Sr(1), one In(2), and one P(1) atom. In the fourth O site, O(5) is bonded in a bent 150 degrees geometry to one In(1) and one P(2) atom. In the fifth O site, O(6) is bonded in a distorted single-bond geometry to one Sr(1) and one P(2) atom. In the sixth O site, O(7) is bonded in a distorted bent 150 degrees geometry to one In(2) and one P(2) atom. In the seventh O site, O(8) is bonded in a distorted bent 150 degrees geometry to one In(1) and one P(2) atom. In the eighth O site, O(1) is bonded in a distorted water-like geometry to one Sr(1) and one P(1) atom.
SrIn2(PO4)4 crystallizes in the orthorhombic C222_1 space group. Sr(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms. Both Sr(1)-O(1) bond lengths are 2.62 Å. Both Sr(1)-O(2) bond lengths are 2.75 Å. Both Sr(1)-O(4) bond lengths are 2.62 Å. Both Sr(1)-O(6) bond lengths are 2.61 Å. There are two inequivalent In sites. In the first In site, In(1) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms to form InO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and corners with four equivalent P(2)O4 tetrahedra. Both In(1)-O(2) bond lengths are 2.17 Å. Both In(1)-O(5) bond lengths are 2.16 Å. Both In(1)-O(8) bond lengths are 2.19 Å. In the second In site, In(2) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms to form InO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. Both In(2)-O(3) bond lengths are 2.17 Å. Both In(2)-O(4) bond lengths are 2.21 Å. Both In(2)-O(7) bond lengths are 2.15 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(4) atom to form PO4 tetrahedra that share  a cornercorner with one In(1)O6 octahedra and corners with two equivalent In(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 37-47°. The P(1)-O(1) bond length is 1.54 Å. The P(1)-O(2) bond length is 1.56 Å. The P(1)-O(3) bond length is 1.54 Å. The P(1)-O(4) bond length is 1.55 Å. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one In(2)O6 octahedra and corners with two equivalent In(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-43°. The P(2)-O(5) bond length is 1.53 Å. The P(2)-O(6) bond length is 1.56 Å. The P(2)-O(7) bond length is 1.53 Å. The P(2)-O(8) bond length is 1.55 Å. There are eight inequivalent O sites. In the first O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1), one In(1), and one P(1) atom. In the second O site, O(3) is bonded in a distorted bent 150 degrees geometry to one In(2) and one P(1) atom. In the third O site, O(4) is bonded in a distorted trigonal planar geometry to one Sr(1), one In(2), and one P(1) atom. In the fourth O site, O(5) is bonded in a bent 150 degrees geometry to one In(1) and one P(2) atom. In the fifth O site, O(6) is bonded in a distorted single-bond geometry to one Sr(1) and one P(2) atom. In the sixth O site, O(7) is bonded in a distorted bent 150 degrees geometry to one In(2) and one P(2) atom. In the seventh O site, O(8) is bonded in a distorted bent 150 degrees geometry to one In(1) and one P(2) atom. In the eighth O site, O(1) is bonded in a distorted water-like geometry to one Sr(1) and one P(1) atom.