SrCaTi2(GeO5)2 crystallizes in the monoclinic P2_1 space group. Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(4), one O(5), one O(6), one O(8), and one O(9) atom. Ca(1) is bonded to one O(10), one O(2), one O(3), one O(5), one O(6), one O(7), and one O(9) atom to form distorted CaO7 pentagonal bipyramids that share corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, edges with two equivalent Ti(1)O6 octahedra, edges with two equivalent Ti(2)O6 octahedra, and  an edgeedge with one Ge(1)O4 tetrahedra. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(8), and one O(9) atom to form TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, and edges with two equivalent Ca(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 31-37°. In the second Ti site, Ti(2) is bonded to one O(1), one O(10), one O(3), one O(4), one O(6), and one O(7) atom to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, and edges with two equivalent Ca(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 31-37°. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(2), one O(6), one O(7), and one O(9) atom to form GeO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 39-56°. In the second Ge site, Ge(2) is bonded to one O(1), one O(10), one O(5), and one O(8) atom to form GeO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, and corners with two equivalent Ca(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 33-56°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Sr(1), one Ti(2), and one Ge(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Ti(1), and one Ge(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1), one Ti(1), and one Ti(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Sr(1), one Ti(1), and one Ti(2) atom. In the fifth O site, O(5) is bonded to one Sr(1), one Ca(1), one Ti(1), and one Ge(2) atom to form distorted corner-sharing OSrCaTiGe tetrahedra. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(1), one Ti(2), and one Ge(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(1), one Ti(2), and one Ge(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Sr(1), one Ti(1), and one Ge(2) atom. In the ninth O site, O(9) is bonded to one Sr(1), one Ca(1), one Ti(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing OSrCaTiGe tetrahedra. In the tenth O site, O(10) is bonded to one Sr(1), one Ca(1), one Ti(2), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing OSrCaTiGe tetrahedra.
SrCaTi2(GeO5)2 crystallizes in the monoclinic P2_1 space group. Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(4), one O(5), one O(6), one O(8), and one O(9) atom. The Sr(1)-O(1) bond length is 2.58 Å. The Sr(1)-O(10) bond length is 2.57 Å. The Sr(1)-O(4) bond length is 2.46 Å. The Sr(1)-O(5) bond length is 2.55 Å. The Sr(1)-O(6) bond length is 2.71 Å. The Sr(1)-O(8) bond length is 2.58 Å. The Sr(1)-O(9) bond length is 2.66 Å. Ca(1) is bonded to one O(10), one O(2), one O(3), one O(5), one O(6), one O(7), and one O(9) atom to form distorted CaO7 pentagonal bipyramids that share corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, edges with two equivalent Ti(1)O6 octahedra, edges with two equivalent Ti(2)O6 octahedra, and  an edgeedge with one Ge(1)O4 tetrahedra. The Ca(1)-O(10) bond length is 2.55 Å. The Ca(1)-O(2) bond length is 2.51 Å. The Ca(1)-O(3) bond length is 2.33 Å. The Ca(1)-O(5) bond length is 2.59 Å. The Ca(1)-O(6) bond length is 2.45 Å. The Ca(1)-O(7) bond length is 2.50 Å. The Ca(1)-O(9) bond length is 2.45 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(8), and one O(9) atom to form TiO6 octahedra that share corners with two equivalent Ti(2)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, and edges with two equivalent Ca(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 31-37°. The Ti(1)-O(2) bond length is 2.01 Å. The Ti(1)-O(3) bond length is 1.80 Å. The Ti(1)-O(4) bond length is 2.03 Å. The Ti(1)-O(5) bond length is 2.04 Å. The Ti(1)-O(8) bond length is 2.00 Å. The Ti(1)-O(9) bond length is 2.05 Å. In the second Ti site, Ti(2) is bonded to one O(1), one O(10), one O(3), one O(4), one O(6), and one O(7) atom to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, and edges with two equivalent Ca(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 31-37°. The Ti(2)-O(1) bond length is 2.02 Å. The Ti(2)-O(10) bond length is 2.05 Å. The Ti(2)-O(3) bond length is 2.02 Å. The Ti(2)-O(4) bond length is 1.80 Å. The Ti(2)-O(6) bond length is 2.05 Å. The Ti(2)-O(7) bond length is 2.00 Å. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(2), one O(6), one O(7), and one O(9) atom to form GeO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 39-56°. The Ge(1)-O(2) bond length is 1.78 Å. The Ge(1)-O(6) bond length is 1.78 Å. The Ge(1)-O(7) bond length is 1.78 Å. The Ge(1)-O(9) bond length is 1.78 Å. In the second Ge site, Ge(2) is bonded to one O(1), one O(10), one O(5), and one O(8) atom to form GeO4 tetrahedra that share corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ti(2)O6 octahedra, and corners with two equivalent Ca(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 33-56°. The Ge(2)-O(1) bond length is 1.78 Å. The Ge(2)-O(10) bond length is 1.78 Å. The Ge(2)-O(5) bond length is 1.77 Å. The Ge(2)-O(8) bond length is 1.78 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Sr(1), one Ti(2), and one Ge(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Ti(1), and one Ge(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1), one Ti(1), and one Ti(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Sr(1), one Ti(1), and one Ti(2) atom. In the fifth O site, O(5) is bonded to one Sr(1), one Ca(1), one Ti(1), and one Ge(2) atom to form distorted corner-sharing OSrCaTiGe tetrahedra. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(1), one Ti(2), and one Ge(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(1), one Ti(2), and one Ge(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Sr(1), one Ti(1), and one Ge(2) atom. In the ninth O site, O(9) is bonded to one Sr(1), one Ca(1), one Ti(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing OSrCaTiGe tetrahedra. In the tenth O site, O(10) is bonded to one Sr(1), one Ca(1), one Ti(2), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing OSrCaTiGe tetrahedra.