Sr2MgRu3O10 crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(1), one O(10), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form distorted SrO7 pentagonal bipyramids that share corners with two equivalent Ru(1)O6 octahedra, corners with two equivalent Ru(3)O6 octahedra,  an edgeedge with one Ru(1)O6 octahedra,  an edgeedge with one Ru(3)O6 octahedra, and edges with two equivalent Ru(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 22-54°. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(10), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. Mg(1) is bonded in a 5-coordinate geometry to one O(10), one O(2), one O(4), one O(5), and one O(6) atom. There are three inequivalent Ru sites. In the first Ru site, Ru(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(8), and one O(9) atom to form RuO6 octahedra that share corners with two equivalent Ru(3)O6 octahedra, corners with two equivalent Sr(1)O7 pentagonal bipyramids, edges with two equivalent Ru(2)O6 octahedra, and  an edgeedge with one Sr(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 42-47°. In the second Ru site, Ru(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form RuO6 octahedra that share corners with two equivalent Ru(3)O6 octahedra, edges with two equivalent Ru(1)O6 octahedra, and edges with two equivalent Sr(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 51-55°. In the third Ru site, Ru(3) is bonded to one O(10), one O(5), one O(6), one O(7), one O(8), and one O(9) atom to form RuO6 octahedra that share corners with two equivalent Ru(1)O6 octahedra, corners with two equivalent Ru(2)O6 octahedra, corners with two equivalent Sr(1)O7 pentagonal bipyramids, and  an edgeedge with one Sr(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 42-55°. 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 Ru(1), and one Ru(2) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to one Sr(2), one Mg(1), one Ru(1), and one Ru(2) atom. In the third O site, O(3) is bonded to one Sr(1), one Sr(2), one Ru(1), and one Ru(2) atom to form distorted OSr2Ru2 trigonal pyramids that share corners with two equivalent O(10)Sr2MgRu trigonal pyramids and edges with two equivalent O(4)Sr2MgRu2 trigonal bipyramids. In the fourth O site, O(4) is bonded to one Sr(1), one Sr(2), one Mg(1), one Ru(1), and one Ru(2) atom to form distorted OSr2MgRu2 trigonal bipyramids that share  a cornercorner with one O(10)Sr2MgRu trigonal pyramid,  an edgeedge with one O(10)Sr2MgRu trigonal pyramid, and edges with two equivalent O(3)Sr2Ru2 trigonal pyramids. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Sr(2), one Mg(1), and one Ru(3) atom. In the sixth O site, O(6) is bonded in a distorted see-saw-like geometry to one Sr(2), one Mg(1), one Ru(2), and one Ru(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Sr(1), one Ru(2), and one Ru(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Ru(1), and one Ru(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Sr(2), one Ru(1), and one Ru(3) atom. In the tenth O site, O(10) is bonded to one Sr(1), one Sr(2), one Mg(1), and one Ru(3) atom to form distorted OSr2MgRu trigonal pyramids that share  a cornercorner with one O(4)Sr2MgRu2 trigonal bipyramid, corners with two equivalent O(3)Sr2Ru2 trigonal pyramids, and  an edgeedge with one O(4)Sr2MgRu2 trigonal bipyramid.
Sr2MgRu3O10 crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(1), one O(10), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form distorted SrO7 pentagonal bipyramids that share corners with two equivalent Ru(1)O6 octahedra, corners with two equivalent Ru(3)O6 octahedra,  an edgeedge with one Ru(1)O6 octahedra,  an edgeedge with one Ru(3)O6 octahedra, and edges with two equivalent Ru(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 22-54°. The Sr(1)-O(1) bond length is 2.51 Å. The Sr(1)-O(10) bond length is 2.57 Å. The Sr(1)-O(3) bond length is 2.61 Å. The Sr(1)-O(4) bond length is 2.58 Å. The Sr(1)-O(5) bond length is 2.56 Å. The Sr(1)-O(7) bond length is 2.63 Å. The Sr(1)-O(8) bond length is 2.54 Å. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(10), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. The Sr(2)-O(10) bond length is 2.41 Å. The Sr(2)-O(2) bond length is 2.63 Å. The Sr(2)-O(3) bond length is 2.50 Å. The Sr(2)-O(4) bond length is 2.72 Å. The Sr(2)-O(5) bond length is 2.62 Å. The Sr(2)-O(6) bond length is 2.44 Å. The Sr(2)-O(9) bond length is 2.51 Å. Mg(1) is bonded in a 5-coordinate geometry to one O(10), one O(2), one O(4), one O(5), and one O(6) atom. The Mg(1)-O(10) bond length is 1.92 Å. The Mg(1)-O(2) bond length is 2.08 Å. The Mg(1)-O(4) bond length is 2.52 Å. The Mg(1)-O(5) bond length is 2.01 Å. The Mg(1)-O(6) bond length is 1.96 Å. There are three inequivalent Ru sites. In the first Ru site, Ru(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(8), and one O(9) atom to form RuO6 octahedra that share corners with two equivalent Ru(3)O6 octahedra, corners with two equivalent Sr(1)O7 pentagonal bipyramids, edges with two equivalent Ru(2)O6 octahedra, and  an edgeedge with one Sr(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 42-47°. The Ru(1)-O(1) bond length is 1.99 Å. The Ru(1)-O(2) bond length is 2.04 Å. The Ru(1)-O(3) bond length is 2.03 Å. The Ru(1)-O(4) bond length is 2.07 Å. The Ru(1)-O(8) bond length is 1.95 Å. The Ru(1)-O(9) bond length is 1.97 Å. In the second Ru site, Ru(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form RuO6 octahedra that share corners with two equivalent Ru(3)O6 octahedra, edges with two equivalent Ru(1)O6 octahedra, and edges with two equivalent Sr(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 51-55°. The Ru(2)-O(1) bond length is 1.95 Å. The Ru(2)-O(2) bond length is 1.99 Å. The Ru(2)-O(3) bond length is 2.01 Å. The Ru(2)-O(4) bond length is 2.06 Å. The Ru(2)-O(6) bond length is 2.13 Å. The Ru(2)-O(7) bond length is 1.96 Å. In the third Ru site, Ru(3) is bonded to one O(10), one O(5), one O(6), one O(7), one O(8), and one O(9) atom to form RuO6 octahedra that share corners with two equivalent Ru(1)O6 octahedra, corners with two equivalent Ru(2)O6 octahedra, corners with two equivalent Sr(1)O7 pentagonal bipyramids, and  an edgeedge with one Sr(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 42-55°. The Ru(3)-O(10) bond length is 2.03 Å. The Ru(3)-O(5) bond length is 1.99 Å. The Ru(3)-O(6) bond length is 2.04 Å. The Ru(3)-O(7) bond length is 1.97 Å. The Ru(3)-O(8) bond length is 1.90 Å. The Ru(3)-O(9) bond length is 1.94 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 Ru(1), and one Ru(2) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to one Sr(2), one Mg(1), one Ru(1), and one Ru(2) atom. In the third O site, O(3) is bonded to one Sr(1), one Sr(2), one Ru(1), and one Ru(2) atom to form distorted OSr2Ru2 trigonal pyramids that share corners with two equivalent O(10)Sr2MgRu trigonal pyramids and edges with two equivalent O(4)Sr2MgRu2 trigonal bipyramids. In the fourth O site, O(4) is bonded to one Sr(1), one Sr(2), one Mg(1), one Ru(1), and one Ru(2) atom to form distorted OSr2MgRu2 trigonal bipyramids that share  a cornercorner with one O(10)Sr2MgRu trigonal pyramid,  an edgeedge with one O(10)Sr2MgRu trigonal pyramid, and edges with two equivalent O(3)Sr2Ru2 trigonal pyramids. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Sr(2), one Mg(1), and one Ru(3) atom. In the sixth O site, O(6) is bonded in a distorted see-saw-like geometry to one Sr(2), one Mg(1), one Ru(2), and one Ru(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Sr(1), one Ru(2), and one Ru(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Ru(1), and one Ru(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Sr(2), one Ru(1), and one Ru(3) atom. In the tenth O site, O(10) is bonded to one Sr(1), one Sr(2), one Mg(1), and one Ru(3) atom to form distorted OSr2MgRu trigonal pyramids that share  a cornercorner with one O(4)Sr2MgRu2 trigonal bipyramid, corners with two equivalent O(3)Sr2Ru2 trigonal pyramids, and  an edgeedge with one O(4)Sr2MgRu2 trigonal bipyramid.