CaYb4(Ru2O7)2 crystallizes in the monoclinic Cm space group. Ca(1) is bonded to one O(5), one O(7), two equivalent O(3), and two equivalent O(6) atoms to form distorted CaO6 octahedra that share corners with three equivalent Yb(1)O8 hexagonal bipyramids, corners with three equivalent Yb(3)O8 hexagonal bipyramids, and corners with six equivalent Yb(2)O8 hexagonal bipyramids. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to one O(1), one O(2), one O(7), one O(9), two equivalent O(3), and two equivalent O(8) atoms to form distorted YbO8 hexagonal bipyramids that share corners with three equivalent Ca(1)O6 octahedra, edges with two equivalent Yb(3)O8 hexagonal bipyramids, and edges with four equivalent Yb(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. In the second Yb site, Yb(2) is bonded to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form distorted YbO8 hexagonal bipyramids that share corners with three equivalent Ca(1)O6 octahedra, edges with two equivalent Yb(1)O8 hexagonal bipyramids, edges with two equivalent Yb(2)O8 hexagonal bipyramids, and edges with two equivalent Yb(3)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 46-47°. In the third Yb site, Yb(3) is bonded to one O(1), one O(2), one O(7), one O(9), two equivalent O(4), and two equivalent O(6) atoms to form distorted YbO8 hexagonal bipyramids that share corners with three equivalent Ca(1)O6 octahedra, edges with two equivalent Yb(1)O8 hexagonal bipyramids, and edges with four equivalent Yb(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. There are three inequivalent Ru sites. In the first Ru site, Ru(1) is bonded in a 6-coordinate geometry to one O(10), one O(5), two equivalent O(4), and two equivalent O(6) atoms. In the second Ru site, Ru(2) is bonded in a 6-coordinate geometry to one O(3), one O(4), one O(6), one O(7), one O(8), and one O(9) atom. In the third Ru site, Ru(3) is bonded in a 6-coordinate geometry to one O(10), one O(5), two equivalent O(3), and two equivalent O(8) atoms. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Yb(1), one Yb(3), and two equivalent Yb(2) atoms to form OYb4 tetrahedra that share corners with two equivalent O(10)Yb2Ru2 tetrahedra, corners with four equivalent O(4)Yb2Ru2 tetrahedra, corners with four equivalent O(8)Yb2Ru2 tetrahedra, and corners with four equivalent O(2)Yb4 tetrahedra. In the second O site, O(2) is bonded to one Yb(1), one Yb(3), and two equivalent Yb(2) atoms to form OYb4 tetrahedra that share corners with four equivalent O(1)Yb4 tetrahedra,  an edgeedge with one O(10)Yb2Ru2 tetrahedra, edges with two equivalent O(4)Yb2Ru2 tetrahedra, and edges with two equivalent O(8)Yb2Ru2 tetrahedra. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ca(1), one Yb(1), one Yb(2), one Ru(2), and one Ru(3) atom. In the fourth O site, O(4) is bonded to one Yb(2), one Yb(3), one Ru(1), and one Ru(2) atom to form distorted OYb2Ru2 tetrahedra that share corners with two equivalent O(10)Yb2Ru2 tetrahedra, corners with two equivalent O(4)Yb2Ru2 tetrahedra, corners with two equivalent O(8)Yb2Ru2 tetrahedra, corners with two equivalent O(1)Yb4 tetrahedra, and  an edgeedge with one O(2)Yb4 tetrahedra. In the fifth O site, O(5) is bonded in a distorted pentagonal planar geometry to one Ca(1), two equivalent Yb(2), one Ru(1), and one Ru(3) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Ca(1), one Yb(2), one Yb(3), one Ru(1), and one Ru(2) atom. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ca(1), one Yb(1), one Yb(3), and two equivalent Ru(2) atoms. In the eighth O site, O(8) is bonded to one Yb(1), one Yb(2), one Ru(2), and one Ru(3) atom to form distorted OYb2Ru2 tetrahedra that share corners with two equivalent O(10)Yb2Ru2 tetrahedra, corners with two equivalent O(4)Yb2Ru2 tetrahedra, corners with two equivalent O(8)Yb2Ru2 tetrahedra, corners with two equivalent O(1)Yb4 tetrahedra, and  an edgeedge with one O(2)Yb4 tetrahedra. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Yb(1), one Yb(3), and two equivalent Ru(2) atoms. In the tenth O site, O(10) is bonded to two equivalent Yb(2), one Ru(1), and one Ru(3) atom to form distorted OYb2Ru2 tetrahedra that share corners with two equivalent O(1)Yb4 tetrahedra, corners with four equivalent O(4)Yb2Ru2 tetrahedra, corners with four equivalent O(8)Yb2Ru2 tetrahedra, and  an edgeedge with one O(2)Yb4 tetrahedra.
CaYb4(Ru2O7)2 crystallizes in the monoclinic Cm space group. Ca(1) is bonded to one O(5), one O(7), two equivalent O(3), and two equivalent O(6) atoms to form distorted CaO6 octahedra that share corners with three equivalent Yb(1)O8 hexagonal bipyramids, corners with three equivalent Yb(3)O8 hexagonal bipyramids, and corners with six equivalent Yb(2)O8 hexagonal bipyramids. The Ca(1)-O(5) bond length is 2.23 Å. The Ca(1)-O(7) bond length is 2.23 Å. Both Ca(1)-O(3) bond lengths are 2.23 Å. Both Ca(1)-O(6) bond lengths are 2.23 Å. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to one O(1), one O(2), one O(7), one O(9), two equivalent O(3), and two equivalent O(8) atoms to form distorted YbO8 hexagonal bipyramids that share corners with three equivalent Ca(1)O6 octahedra, edges with two equivalent Yb(3)O8 hexagonal bipyramids, and edges with four equivalent Yb(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. The Yb(1)-O(1) bond length is 2.26 Å. The Yb(1)-O(2) bond length is 2.30 Å. The Yb(1)-O(7) bond length is 2.54 Å. The Yb(1)-O(9) bond length is 2.66 Å. Both Yb(1)-O(3) bond lengths are 2.52 Å. Both Yb(1)-O(8) bond lengths are 2.65 Å. In the second Yb site, Yb(2) is bonded to one O(1), one O(10), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form distorted YbO8 hexagonal bipyramids that share corners with three equivalent Ca(1)O6 octahedra, edges with two equivalent Yb(1)O8 hexagonal bipyramids, edges with two equivalent Yb(2)O8 hexagonal bipyramids, and edges with two equivalent Yb(3)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 46-47°. The Yb(2)-O(1) bond length is 2.26 Å. The Yb(2)-O(10) bond length is 2.65 Å. The Yb(2)-O(2) bond length is 2.30 Å. The Yb(2)-O(3) bond length is 2.52 Å. The Yb(2)-O(4) bond length is 2.66 Å. The Yb(2)-O(5) bond length is 2.51 Å. The Yb(2)-O(6) bond length is 2.53 Å. The Yb(2)-O(8) bond length is 2.66 Å. In the third Yb site, Yb(3) is bonded to one O(1), one O(2), one O(7), one O(9), two equivalent O(4), and two equivalent O(6) atoms to form distorted YbO8 hexagonal bipyramids that share corners with three equivalent Ca(1)O6 octahedra, edges with two equivalent Yb(1)O8 hexagonal bipyramids, and edges with four equivalent Yb(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 47°. The Yb(3)-O(1) bond length is 2.24 Å. The Yb(3)-O(2) bond length is 2.29 Å. The Yb(3)-O(7) bond length is 2.53 Å. The Yb(3)-O(9) bond length is 2.65 Å. Both Yb(3)-O(4) bond lengths are 2.65 Å. Both Yb(3)-O(6) bond lengths are 2.52 Å. There are three inequivalent Ru sites. In the first Ru site, Ru(1) is bonded in a 6-coordinate geometry to one O(10), one O(5), two equivalent O(4), and two equivalent O(6) atoms. The Ru(1)-O(10) bond length is 1.90 Å. The Ru(1)-O(5) bond length is 2.19 Å. Both Ru(1)-O(4) bond lengths are 1.90 Å. Both Ru(1)-O(6) bond lengths are 2.17 Å. In the second Ru site, Ru(2) is bonded in a 6-coordinate geometry to one O(3), one O(4), one O(6), one O(7), one O(8), and one O(9) atom. The Ru(2)-O(3) bond length is 2.18 Å. The Ru(2)-O(4) bond length is 1.90 Å. The Ru(2)-O(6) bond length is 2.17 Å. The Ru(2)-O(7) bond length is 2.16 Å. The Ru(2)-O(8) bond length is 1.90 Å. The Ru(2)-O(9) bond length is 1.90 Å. In the third Ru site, Ru(3) is bonded in a 6-coordinate geometry to one O(10), one O(5), two equivalent O(3), and two equivalent O(8) atoms. The Ru(3)-O(10) bond length is 1.90 Å. The Ru(3)-O(5) bond length is 2.18 Å. Both Ru(3)-O(3) bond lengths are 2.18 Å. Both Ru(3)-O(8) bond lengths are 1.90 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Yb(1), one Yb(3), and two equivalent Yb(2) atoms to form OYb4 tetrahedra that share corners with two equivalent O(10)Yb2Ru2 tetrahedra, corners with four equivalent O(4)Yb2Ru2 tetrahedra, corners with four equivalent O(8)Yb2Ru2 tetrahedra, and corners with four equivalent O(2)Yb4 tetrahedra. In the second O site, O(2) is bonded to one Yb(1), one Yb(3), and two equivalent Yb(2) atoms to form OYb4 tetrahedra that share corners with four equivalent O(1)Yb4 tetrahedra,  an edgeedge with one O(10)Yb2Ru2 tetrahedra, edges with two equivalent O(4)Yb2Ru2 tetrahedra, and edges with two equivalent O(8)Yb2Ru2 tetrahedra. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ca(1), one Yb(1), one Yb(2), one Ru(2), and one Ru(3) atom. In the fourth O site, O(4) is bonded to one Yb(2), one Yb(3), one Ru(1), and one Ru(2) atom to form distorted OYb2Ru2 tetrahedra that share corners with two equivalent O(10)Yb2Ru2 tetrahedra, corners with two equivalent O(4)Yb2Ru2 tetrahedra, corners with two equivalent O(8)Yb2Ru2 tetrahedra, corners with two equivalent O(1)Yb4 tetrahedra, and  an edgeedge with one O(2)Yb4 tetrahedra. In the fifth O site, O(5) is bonded in a distorted pentagonal planar geometry to one Ca(1), two equivalent Yb(2), one Ru(1), and one Ru(3) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Ca(1), one Yb(2), one Yb(3), one Ru(1), and one Ru(2) atom. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ca(1), one Yb(1), one Yb(3), and two equivalent Ru(2) atoms. In the eighth O site, O(8) is bonded to one Yb(1), one Yb(2), one Ru(2), and one Ru(3) atom to form distorted OYb2Ru2 tetrahedra that share corners with two equivalent O(10)Yb2Ru2 tetrahedra, corners with two equivalent O(4)Yb2Ru2 tetrahedra, corners with two equivalent O(8)Yb2Ru2 tetrahedra, corners with two equivalent O(1)Yb4 tetrahedra, and  an edgeedge with one O(2)Yb4 tetrahedra. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Yb(1), one Yb(3), and two equivalent Ru(2) atoms. In the tenth O site, O(10) is bonded to two equivalent Yb(2), one Ru(1), and one Ru(3) atom to form distorted OYb2Ru2 tetrahedra that share corners with two equivalent O(1)Yb4 tetrahedra, corners with four equivalent O(4)Yb2Ru2 tetrahedra, corners with four equivalent O(8)Yb2Ru2 tetrahedra, and  an edgeedge with one O(2)Yb4 tetrahedra.