Sr4CaYGa2(Cu2O7)2 crystallizes in the monoclinic C2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(6), one O(7), two equivalent O(4), and two equivalent O(5) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(6), one O(7), two equivalent O(4), and two equivalent O(5) atoms. Ca(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(6), and two equivalent O(7) atoms. Y(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(6), and two equivalent O(7) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form CuO5 square pyramids that share corners with four equivalent Cu(2)O5 square pyramids and  a cornercorner with one Ga(1)O4 tetrahedra. In the second Cu site, Cu(2) is bonded to one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form CuO5 square pyramids that share corners with four equivalent Cu(1)O5 square pyramids and  a cornercorner with one Ga(1)O4 tetrahedra. Ga(1) is bonded to one O(4), one O(5), and two equivalent O(1) atoms to form GaO4 tetrahedra that share  a cornercorner with one Cu(1)O5 square pyramid,  a cornercorner with one Cu(2)O5 square pyramid, and corners with two equivalent Ga(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Cu(1), and one Ga(1) atom. In the second O site, O(6) is bonded to one Sr(1), one Sr(2), one Ca(1), one Y(1), one Cu(1), and one Cu(2) atom to form distorted OSr2CaYCu2 octahedra that share corners with two equivalent O(6)Sr2CaYCu2 octahedra, corners with two equivalent O(7)Sr2CaYCu2 octahedra, corners with four equivalent O(2)Sr2CaYCu2 octahedra, corners with two equivalent O(1)Sr2Ga2 tetrahedra,  an edgeedge with one O(3)Sr2CaYCu2 octahedra, edges with two equivalent O(2)Sr2CaYCu2 octahedra, faces with two equivalent O(3)Sr2CaYCu2 octahedra, and faces with two equivalent O(7)Sr2CaYCu2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the third O site, O(7) is bonded to one Sr(1), one Sr(2), one Ca(1), one Y(1), one Cu(1), and one Cu(2) atom to form distorted OSr2CaYCu2 octahedra that share corners with two equivalent O(6)Sr2CaYCu2 octahedra, corners with two equivalent O(7)Sr2CaYCu2 octahedra, corners with four equivalent O(3)Sr2CaYCu2 octahedra, corners with two equivalent O(1)Sr2Ga2 tetrahedra,  an edgeedge with one O(2)Sr2CaYCu2 octahedra, edges with two equivalent O(3)Sr2CaYCu2 octahedra, faces with two equivalent O(2)Sr2CaYCu2 octahedra, and faces with two equivalent O(6)Sr2CaYCu2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the fourth O site, O(1) is bonded to one Sr(1), one Sr(2), and two equivalent Ga(1) atoms to form distorted OSr2Ga2 tetrahedra that share corners with two equivalent O(2)Sr2CaYCu2 octahedra, corners with two equivalent O(3)Sr2CaYCu2 octahedra, corners with two equivalent O(6)Sr2CaYCu2 octahedra, corners with two equivalent O(7)Sr2CaYCu2 octahedra, and corners with two equivalent O(1)Sr2Ga2 tetrahedra. The corner-sharing octahedral tilt angles range from 21-68°. In the fifth O site, O(2) is bonded to one Sr(1), one Sr(2), one Ca(1), one Y(1), one Cu(1), and one Cu(2) atom to form distorted OSr2CaYCu2 octahedra that share corners with two equivalent O(2)Sr2CaYCu2 octahedra, corners with two equivalent O(3)Sr2CaYCu2 octahedra, corners with four equivalent O(6)Sr2CaYCu2 octahedra, corners with two equivalent O(1)Sr2Ga2 tetrahedra,  an edgeedge with one O(7)Sr2CaYCu2 octahedra, edges with two equivalent O(6)Sr2CaYCu2 octahedra, faces with two equivalent O(3)Sr2CaYCu2 octahedra, and faces with two equivalent O(7)Sr2CaYCu2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the sixth O site, O(3) is bonded to one Sr(1), one Sr(2), one Ca(1), one Y(1), one Cu(1), and one Cu(2) atom to form distorted OSr2CaYCu2 octahedra that share corners with two equivalent O(2)Sr2CaYCu2 octahedra, corners with two equivalent O(3)Sr2CaYCu2 octahedra, corners with four equivalent O(7)Sr2CaYCu2 octahedra, corners with two equivalent O(1)Sr2Ga2 tetrahedra,  an edgeedge with one O(6)Sr2CaYCu2 octahedra, edges with two equivalent O(7)Sr2CaYCu2 octahedra, faces with two equivalent O(2)Sr2CaYCu2 octahedra, and faces with two equivalent O(6)Sr2CaYCu2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the seventh O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Cu(2), and one Ga(1) atom.
Sr4CaYGa2(Cu2O7)2 crystallizes in the monoclinic C2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(6), one O(7), two equivalent O(4), and two equivalent O(5) atoms. The Sr(1)-O(1) bond length is 2.48 Å. The Sr(1)-O(2) bond length is 2.79 Å. The Sr(1)-O(3) bond length is 2.78 Å. The Sr(1)-O(6) bond length is 2.80 Å. The Sr(1)-O(7) bond length is 2.81 Å. There is one shorter (2.50 Å) and one longer (3.13 Å) Sr(1)-O(4) bond length. There is one shorter (2.67 Å) and one longer (2.87 Å) Sr(1)-O(5) bond length. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(6), one O(7), two equivalent O(4), and two equivalent O(5) atoms. The Sr(2)-O(1) bond length is 2.48 Å. The Sr(2)-O(2) bond length is 2.75 Å. The Sr(2)-O(3) bond length is 2.76 Å. The Sr(2)-O(6) bond length is 2.77 Å. The Sr(2)-O(7) bond length is 2.76 Å. There is one shorter (2.67 Å) and one longer (2.86 Å) Sr(2)-O(4) bond length. There is one shorter (2.51 Å) and one longer (3.12 Å) Sr(2)-O(5) bond length. Ca(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(6), and two equivalent O(7) atoms. Both Ca(1)-O(2) bond lengths are 2.44 Å. Both Ca(1)-O(3) bond lengths are 2.45 Å. Both Ca(1)-O(6) bond lengths are 2.51 Å. Both Ca(1)-O(7) bond lengths are 2.51 Å. Y(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(6), and two equivalent O(7) atoms. Both Y(1)-O(2) bond lengths are 2.39 Å. Both Y(1)-O(3) bond lengths are 2.39 Å. Both Y(1)-O(6) bond lengths are 2.44 Å. Both Y(1)-O(7) bond lengths are 2.44 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form CuO5 square pyramids that share corners with four equivalent Cu(2)O5 square pyramids and  a cornercorner with one Ga(1)O4 tetrahedra. The Cu(1)-O(2) bond length is 1.95 Å. The Cu(1)-O(3) bond length is 1.95 Å. The Cu(1)-O(5) bond length is 2.41 Å. The Cu(1)-O(6) bond length is 1.93 Å. The Cu(1)-O(7) bond length is 1.93 Å. In the second Cu site, Cu(2) is bonded to one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form CuO5 square pyramids that share corners with four equivalent Cu(1)O5 square pyramids and  a cornercorner with one Ga(1)O4 tetrahedra. The Cu(2)-O(2) bond length is 1.94 Å. The Cu(2)-O(3) bond length is 1.94 Å. The Cu(2)-O(4) bond length is 2.40 Å. The Cu(2)-O(6) bond length is 1.93 Å. The Cu(2)-O(7) bond length is 1.93 Å. Ga(1) is bonded to one O(4), one O(5), and two equivalent O(1) atoms to form GaO4 tetrahedra that share  a cornercorner with one Cu(1)O5 square pyramid,  a cornercorner with one Cu(2)O5 square pyramid, and corners with two equivalent Ga(1)O4 tetrahedra. The Ga(1)-O(4) bond length is 1.85 Å. The Ga(1)-O(5) bond length is 1.85 Å. There is one shorter (1.91 Å) and one longer (1.92 Å) Ga(1)-O(1) bond length. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Cu(1), and one Ga(1) atom. In the second O site, O(6) is bonded to one Sr(1), one Sr(2), one Ca(1), one Y(1), one Cu(1), and one Cu(2) atom to form distorted OSr2CaYCu2 octahedra that share corners with two equivalent O(6)Sr2CaYCu2 octahedra, corners with two equivalent O(7)Sr2CaYCu2 octahedra, corners with four equivalent O(2)Sr2CaYCu2 octahedra, corners with two equivalent O(1)Sr2Ga2 tetrahedra,  an edgeedge with one O(3)Sr2CaYCu2 octahedra, edges with two equivalent O(2)Sr2CaYCu2 octahedra, faces with two equivalent O(3)Sr2CaYCu2 octahedra, and faces with two equivalent O(7)Sr2CaYCu2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the third O site, O(7) is bonded to one Sr(1), one Sr(2), one Ca(1), one Y(1), one Cu(1), and one Cu(2) atom to form distorted OSr2CaYCu2 octahedra that share corners with two equivalent O(6)Sr2CaYCu2 octahedra, corners with two equivalent O(7)Sr2CaYCu2 octahedra, corners with four equivalent O(3)Sr2CaYCu2 octahedra, corners with two equivalent O(1)Sr2Ga2 tetrahedra,  an edgeedge with one O(2)Sr2CaYCu2 octahedra, edges with two equivalent O(3)Sr2CaYCu2 octahedra, faces with two equivalent O(2)Sr2CaYCu2 octahedra, and faces with two equivalent O(6)Sr2CaYCu2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the fourth O site, O(1) is bonded to one Sr(1), one Sr(2), and two equivalent Ga(1) atoms to form distorted OSr2Ga2 tetrahedra that share corners with two equivalent O(2)Sr2CaYCu2 octahedra, corners with two equivalent O(3)Sr2CaYCu2 octahedra, corners with two equivalent O(6)Sr2CaYCu2 octahedra, corners with two equivalent O(7)Sr2CaYCu2 octahedra, and corners with two equivalent O(1)Sr2Ga2 tetrahedra. The corner-sharing octahedral tilt angles range from 21-68°. In the fifth O site, O(2) is bonded to one Sr(1), one Sr(2), one Ca(1), one Y(1), one Cu(1), and one Cu(2) atom to form distorted OSr2CaYCu2 octahedra that share corners with two equivalent O(2)Sr2CaYCu2 octahedra, corners with two equivalent O(3)Sr2CaYCu2 octahedra, corners with four equivalent O(6)Sr2CaYCu2 octahedra, corners with two equivalent O(1)Sr2Ga2 tetrahedra,  an edgeedge with one O(7)Sr2CaYCu2 octahedra, edges with two equivalent O(6)Sr2CaYCu2 octahedra, faces with two equivalent O(3)Sr2CaYCu2 octahedra, and faces with two equivalent O(7)Sr2CaYCu2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the sixth O site, O(3) is bonded to one Sr(1), one Sr(2), one Ca(1), one Y(1), one Cu(1), and one Cu(2) atom to form distorted OSr2CaYCu2 octahedra that share corners with two equivalent O(2)Sr2CaYCu2 octahedra, corners with two equivalent O(3)Sr2CaYCu2 octahedra, corners with four equivalent O(7)Sr2CaYCu2 octahedra, corners with two equivalent O(1)Sr2Ga2 tetrahedra,  an edgeedge with one O(6)Sr2CaYCu2 octahedra, edges with two equivalent O(7)Sr2CaYCu2 octahedra, faces with two equivalent O(2)Sr2CaYCu2 octahedra, and faces with two equivalent O(6)Sr2CaYCu2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the seventh O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Cu(2), and one Ga(1) atom.