Sr2Co2GaAlO7 crystallizes in the triclinic P1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one O(1), one O(14), one O(7), two equivalent O(11), and two equivalent O(12) atoms. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one O(2), one O(4), one O(6), one O(9), and two equivalent O(10) atoms. In the third Sr site, Sr(3) is bonded in a 6-coordinate geometry to one O(13), one O(2), one O(3), two equivalent O(11), and two equivalent O(12) atoms. In the fourth Sr site, Sr(4) is bonded in a 6-coordinate geometry to one O(5), one O(7), one O(8), two equivalent O(10), and two equivalent O(4) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(10), one O(5), one O(6), one O(8), and one O(9) atom to form distorted CoO5 square pyramids that share  a cornercorner with one Ga(1)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with two equivalent Al(2)O4 tetrahedra. In the second Co site, Co(2) is bonded to one O(1), one O(11), one O(13), one O(14), and one O(3) atom to form distorted CoO5 square pyramids that share corners with four equivalent Co(4)O5 square pyramids,  a cornercorner with one Ga(1)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with two equivalent Al(2)O4 tetrahedra. In the third Co site, Co(3) is bonded in a distorted rectangular see-saw-like geometry to one O(4), one O(5), one O(6), one O(8), and one O(9) atom. In the fourth Co site, Co(4) is bonded to one O(1), one O(12), one O(13), one O(14), and one O(3) atom to form distorted CoO5 square pyramids that share corners with four equivalent Co(2)O5 square pyramids,  a cornercorner with one Ga(2)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with two equivalent Al(2)O4 tetrahedra. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(10), one O(11), one O(2), and one O(7) atom to form GaO4 tetrahedra that share  a cornercorner with one Co(1)O5 square pyramid,  a cornercorner with one Co(2)O5 square pyramid, and corners with two equivalent Ga(2)O4 tetrahedra. In the second Ga site, Ga(2) is bonded to one O(12), one O(2), one O(4), and one O(7) atom to form GaO4 tetrahedra that share  a cornercorner with one Co(4)O5 square pyramid and corners with two equivalent Ga(1)O4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(13), one O(3), one O(5), and one O(8) atom to form AlO4 tetrahedra that share corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(2)O5 square pyramids, and corners with two equivalent Co(4)O5 square pyramids. In the second Al site, Al(2) is bonded to one O(1), one O(14), one O(6), and one O(9) atom to form AlO4 tetrahedra that share corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(2)O5 square pyramids, and corners with two equivalent Co(4)O5 square pyramids. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Co(2), one Co(4), and one Al(2) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(7)Sr2Ga2 tetrahedra,  a cornercorner with one O(9)SrAlCo2 trigonal pyramid, corners with two equivalent O(13)SrAlCo2 trigonal pyramids, corners with two equivalent O(14)SrAlCo2 trigonal pyramids, corners with two equivalent O(3)SrAlCo2 trigonal pyramids, and  an edgeedge with one O(14)SrAlCo2 trigonal pyramid. In the second O site, O(2) is bonded to one Sr(2), one Sr(3), one Ga(1), and one Ga(2) atom to form distorted OSr2Ga2 tetrahedra that share corners with two equivalent O(7)Sr2Ga2 tetrahedra,  a cornercorner with one O(13)SrAlCo2 trigonal pyramid,  a cornercorner with one O(3)SrAlCo2 trigonal pyramid, and  a cornercorner with one O(9)SrAlCo2 trigonal pyramid. In the third O site, O(3) is bonded to one Sr(3), one Co(2), one Co(4), and one Al(1) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(2)Sr2Ga2 tetrahedra,  a cornercorner with one O(5)SrAlCo2 trigonal pyramid, corners with two equivalent O(1)SrAlCo2 trigonal pyramids, corners with two equivalent O(13)SrAlCo2 trigonal pyramids, corners with two equivalent O(14)SrAlCo2 trigonal pyramids, and  an edgeedge with one O(13)SrAlCo2 trigonal pyramid. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Sr(2), two equivalent Sr(4), one Co(3), and one Ga(2) atom. In the fifth O site, O(5) is bonded to one Sr(4), one Co(1), one Co(3), and one Al(1) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(7)Sr2Ga2 tetrahedra,  a cornercorner with one O(13)SrAlCo2 trigonal pyramid,  a cornercorner with one O(3)SrAlCo2 trigonal pyramid, and corners with two equivalent O(9)SrAlCo2 trigonal pyramids. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(2), one Co(1), one Co(3), and one Al(2) atom. In the seventh O site, O(7) is bonded to one Sr(1), one Sr(4), one Ga(1), and one Ga(2) atom to form distorted OSr2Ga2 tetrahedra that share corners with two equivalent O(2)Sr2Ga2 tetrahedra,  a cornercorner with one O(1)SrAlCo2 trigonal pyramid,  a cornercorner with one O(14)SrAlCo2 trigonal pyramid, and  a cornercorner with one O(5)SrAlCo2 trigonal pyramid. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Sr(4), one Co(1), one Co(3), and one Al(1) atom. In the ninth O site, O(9) is bonded to one Sr(2), one Co(1), one Co(3), and one Al(2) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(2)Sr2Ga2 tetrahedra,  a cornercorner with one O(1)SrAlCo2 trigonal pyramid,  a cornercorner with one O(14)SrAlCo2 trigonal pyramid, and corners with two equivalent O(5)SrAlCo2 trigonal pyramids. In the tenth O site, O(10) is bonded in a 6-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), one Co(1), and one Ga(1) atom. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), one Co(2), and one Ga(1) atom. In the twelfth O site, O(12) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), one Co(4), and one Ga(2) atom. In the thirteenth O site, O(13) is bonded to one Sr(3), one Co(2), one Co(4), and one Al(1) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(2)Sr2Ga2 tetrahedra,  a cornercorner with one O(5)SrAlCo2 trigonal pyramid, corners with two equivalent O(1)SrAlCo2 trigonal pyramids, corners with two equivalent O(14)SrAlCo2 trigonal pyramids, corners with two equivalent O(3)SrAlCo2 trigonal pyramids, and  an edgeedge with one O(3)SrAlCo2 trigonal pyramid. In the fourteenth O site, O(14) is bonded to one Sr(1), one Co(2), one Co(4), and one Al(2) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(7)Sr2Ga2 tetrahedra,  a cornercorner with one O(9)SrAlCo2 trigonal pyramid, corners with two equivalent O(1)SrAlCo2 trigonal pyramids, corners with two equivalent O(13)SrAlCo2 trigonal pyramids, corners with two equivalent O(3)SrAlCo2 trigonal pyramids, and  an edgeedge with one O(1)SrAlCo2 trigonal pyramid.
Sr2Co2GaAlO7 crystallizes in the triclinic P1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one O(1), one O(14), one O(7), two equivalent O(11), and two equivalent O(12) atoms. The Sr(1)-O(1) bond length is 2.51 Å. The Sr(1)-O(14) bond length is 2.49 Å. The Sr(1)-O(7) bond length is 2.47 Å. There is one shorter (2.50 Å) and one longer (3.24 Å) Sr(1)-O(11) bond length. There is one shorter (2.62 Å) and one longer (2.88 Å) Sr(1)-O(12) bond length. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one O(2), one O(4), one O(6), one O(9), and two equivalent O(10) atoms. The Sr(2)-O(2) bond length is 2.47 Å. The Sr(2)-O(4) bond length is 2.48 Å. The Sr(2)-O(6) bond length is 2.51 Å. The Sr(2)-O(9) bond length is 2.52 Å. There is one shorter (2.62 Å) and one longer (2.88 Å) Sr(2)-O(10) bond length. In the third Sr site, Sr(3) is bonded in a 6-coordinate geometry to one O(13), one O(2), one O(3), two equivalent O(11), and two equivalent O(12) atoms. The Sr(3)-O(13) bond length is 2.48 Å. The Sr(3)-O(2) bond length is 2.47 Å. The Sr(3)-O(3) bond length is 2.51 Å. There is one shorter (2.62 Å) and one longer (2.90 Å) Sr(3)-O(11) bond length. There is one shorter (2.49 Å) and one longer (3.22 Å) Sr(3)-O(12) bond length. In the fourth Sr site, Sr(4) is bonded in a 6-coordinate geometry to one O(5), one O(7), one O(8), two equivalent O(10), and two equivalent O(4) atoms. The Sr(4)-O(5) bond length is 2.52 Å. The Sr(4)-O(7) bond length is 2.47 Å. The Sr(4)-O(8) bond length is 2.53 Å. There is one shorter (2.50 Å) and one longer (3.22 Å) Sr(4)-O(10) bond length. There is one shorter (2.62 Å) and one longer (2.92 Å) Sr(4)-O(4) bond length. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(10), one O(5), one O(6), one O(8), and one O(9) atom to form distorted CoO5 square pyramids that share  a cornercorner with one Ga(1)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with two equivalent Al(2)O4 tetrahedra. The Co(1)-O(10) bond length is 2.40 Å. The Co(1)-O(5) bond length is 2.10 Å. The Co(1)-O(6) bond length is 1.98 Å. The Co(1)-O(8) bond length is 2.20 Å. The Co(1)-O(9) bond length is 2.00 Å. In the second Co site, Co(2) is bonded to one O(1), one O(11), one O(13), one O(14), and one O(3) atom to form distorted CoO5 square pyramids that share corners with four equivalent Co(4)O5 square pyramids,  a cornercorner with one Ga(1)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with two equivalent Al(2)O4 tetrahedra. The Co(2)-O(1) bond length is 2.12 Å. The Co(2)-O(11) bond length is 2.48 Å. The Co(2)-O(13) bond length is 2.03 Å. The Co(2)-O(14) bond length is 2.05 Å. The Co(2)-O(3) bond length is 2.02 Å. In the third Co site, Co(3) is bonded in a distorted rectangular see-saw-like geometry to one O(4), one O(5), one O(6), one O(8), and one O(9) atom. The Co(3)-O(4) bond length is 2.67 Å. The Co(3)-O(5) bond length is 1.95 Å. The Co(3)-O(6) bond length is 2.11 Å. The Co(3)-O(8) bond length is 1.93 Å. The Co(3)-O(9) bond length is 2.12 Å. In the fourth Co site, Co(4) is bonded to one O(1), one O(12), one O(13), one O(14), and one O(3) atom to form distorted CoO5 square pyramids that share corners with four equivalent Co(2)O5 square pyramids,  a cornercorner with one Ga(2)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with two equivalent Al(2)O4 tetrahedra. The Co(4)-O(1) bond length is 2.02 Å. The Co(4)-O(12) bond length is 2.34 Å. The Co(4)-O(13) bond length is 2.04 Å. The Co(4)-O(14) bond length is 2.01 Å. The Co(4)-O(3) bond length is 2.13 Å. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(10), one O(11), one O(2), and one O(7) atom to form GaO4 tetrahedra that share  a cornercorner with one Co(1)O5 square pyramid,  a cornercorner with one Co(2)O5 square pyramid, and corners with two equivalent Ga(2)O4 tetrahedra. The Ga(1)-O(10) bond length is 1.88 Å. The Ga(1)-O(11) bond length is 1.86 Å. The Ga(1)-O(2) bond length is 1.91 Å. The Ga(1)-O(7) bond length is 1.89 Å. In the second Ga site, Ga(2) is bonded to one O(12), one O(2), one O(4), and one O(7) atom to form GaO4 tetrahedra that share  a cornercorner with one Co(4)O5 square pyramid and corners with two equivalent Ga(1)O4 tetrahedra. The Ga(2)-O(12) bond length is 1.87 Å. The Ga(2)-O(2) bond length is 1.90 Å. The Ga(2)-O(4) bond length is 1.84 Å. The Ga(2)-O(7) bond length is 1.91 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(13), one O(3), one O(5), and one O(8) atom to form AlO4 tetrahedra that share corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(2)O5 square pyramids, and corners with two equivalent Co(4)O5 square pyramids. The Al(1)-O(13) bond length is 1.82 Å. The Al(1)-O(3) bond length is 1.82 Å. The Al(1)-O(5) bond length is 1.85 Å. The Al(1)-O(8) bond length is 1.84 Å. In the second Al site, Al(2) is bonded to one O(1), one O(14), one O(6), and one O(9) atom to form AlO4 tetrahedra that share corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(2)O5 square pyramids, and corners with two equivalent Co(4)O5 square pyramids. The Al(2)-O(1) bond length is 1.82 Å. The Al(2)-O(14) bond length is 1.83 Å. The Al(2)-O(6) bond length is 1.84 Å. The Al(2)-O(9) bond length is 1.83 Å. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Co(2), one Co(4), and one Al(2) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(7)Sr2Ga2 tetrahedra,  a cornercorner with one O(9)SrAlCo2 trigonal pyramid, corners with two equivalent O(13)SrAlCo2 trigonal pyramids, corners with two equivalent O(14)SrAlCo2 trigonal pyramids, corners with two equivalent O(3)SrAlCo2 trigonal pyramids, and  an edgeedge with one O(14)SrAlCo2 trigonal pyramid. In the second O site, O(2) is bonded to one Sr(2), one Sr(3), one Ga(1), and one Ga(2) atom to form distorted OSr2Ga2 tetrahedra that share corners with two equivalent O(7)Sr2Ga2 tetrahedra,  a cornercorner with one O(13)SrAlCo2 trigonal pyramid,  a cornercorner with one O(3)SrAlCo2 trigonal pyramid, and  a cornercorner with one O(9)SrAlCo2 trigonal pyramid. In the third O site, O(3) is bonded to one Sr(3), one Co(2), one Co(4), and one Al(1) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(2)Sr2Ga2 tetrahedra,  a cornercorner with one O(5)SrAlCo2 trigonal pyramid, corners with two equivalent O(1)SrAlCo2 trigonal pyramids, corners with two equivalent O(13)SrAlCo2 trigonal pyramids, corners with two equivalent O(14)SrAlCo2 trigonal pyramids, and  an edgeedge with one O(13)SrAlCo2 trigonal pyramid. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Sr(2), two equivalent Sr(4), one Co(3), and one Ga(2) atom. In the fifth O site, O(5) is bonded to one Sr(4), one Co(1), one Co(3), and one Al(1) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(7)Sr2Ga2 tetrahedra,  a cornercorner with one O(13)SrAlCo2 trigonal pyramid,  a cornercorner with one O(3)SrAlCo2 trigonal pyramid, and corners with two equivalent O(9)SrAlCo2 trigonal pyramids. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(2), one Co(1), one Co(3), and one Al(2) atom. In the seventh O site, O(7) is bonded to one Sr(1), one Sr(4), one Ga(1), and one Ga(2) atom to form distorted OSr2Ga2 tetrahedra that share corners with two equivalent O(2)Sr2Ga2 tetrahedra,  a cornercorner with one O(1)SrAlCo2 trigonal pyramid,  a cornercorner with one O(14)SrAlCo2 trigonal pyramid, and  a cornercorner with one O(5)SrAlCo2 trigonal pyramid. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Sr(4), one Co(1), one Co(3), and one Al(1) atom. In the ninth O site, O(9) is bonded to one Sr(2), one Co(1), one Co(3), and one Al(2) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(2)Sr2Ga2 tetrahedra,  a cornercorner with one O(1)SrAlCo2 trigonal pyramid,  a cornercorner with one O(14)SrAlCo2 trigonal pyramid, and corners with two equivalent O(5)SrAlCo2 trigonal pyramids. In the tenth O site, O(10) is bonded in a 6-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), one Co(1), and one Ga(1) atom. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), one Co(2), and one Ga(1) atom. In the twelfth O site, O(12) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), one Co(4), and one Ga(2) atom. In the thirteenth O site, O(13) is bonded to one Sr(3), one Co(2), one Co(4), and one Al(1) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(2)Sr2Ga2 tetrahedra,  a cornercorner with one O(5)SrAlCo2 trigonal pyramid, corners with two equivalent O(1)SrAlCo2 trigonal pyramids, corners with two equivalent O(14)SrAlCo2 trigonal pyramids, corners with two equivalent O(3)SrAlCo2 trigonal pyramids, and  an edgeedge with one O(3)SrAlCo2 trigonal pyramid. In the fourteenth O site, O(14) is bonded to one Sr(1), one Co(2), one Co(4), and one Al(2) atom to form distorted OSrAlCo2 trigonal pyramids that share  a cornercorner with one O(7)Sr2Ga2 tetrahedra,  a cornercorner with one O(9)SrAlCo2 trigonal pyramid, corners with two equivalent O(1)SrAlCo2 trigonal pyramids, corners with two equivalent O(13)SrAlCo2 trigonal pyramids, corners with two equivalent O(3)SrAlCo2 trigonal pyramids, and  an edgeedge with one O(1)SrAlCo2 trigonal pyramid.