Ca2Dy3Sb3O14 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a body-centered cubic geometry to two equivalent O(4), two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms. In the second Ca site, Ca(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(4) and two equivalent O(6) atoms. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(5), and two equivalent O(7) atoms. In the second Dy site, Dy(2) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted DyO6 octahedra that share  a cornercorner with one Sb(2)O6 octahedra, corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(3)O6 octahedra, and  an edgeedge with one Sb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-62°. There are three inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form SbO6 octahedra that share corners with two equivalent Sb(2)O6 octahedra, corners with two equivalent Sb(3)O6 octahedra, and corners with four equivalent Dy(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-59°. In the second Sb site, Sb(2) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form SbO6 octahedra that share corners with two equivalent Dy(2)O6 octahedra, corners with two equivalent Sb(1)O6 octahedra, and edges with two equivalent Dy(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-62°. In the third Sb site, Sb(3) is bonded to two equivalent O(2), two equivalent O(6), and two equivalent O(7) atoms to form SbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra and corners with four equivalent Dy(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-50°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Dy(2), one Sb(1), and one Sb(2) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Dy(1), one Sb(1), and one Sb(3) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Dy(1), one Dy(2), and one Sb(1) atom. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), one Dy(2), and one Sb(2) atom to form distorted OCa2DySb tetrahedra that share corners with three equivalent O(4)Ca2DySb tetrahedra, corners with three equivalent O(6)Ca2DySb tetrahedra,  a cornercorner with one O(7)CaDy2Sb trigonal pyramid, corners with three equivalent O(5)CaDy2Sb trigonal pyramids,  an edgeedge with one O(6)Ca2DySb tetrahedra,  an edgeedge with one O(5)CaDy2Sb trigonal pyramid, and  an edgeedge with one O(7)CaDy2Sb trigonal pyramid. In the fifth O site, O(5) is bonded to one Ca(1), one Dy(1), one Dy(2), and one Sb(2) atom to form distorted OCaDy2Sb trigonal pyramids that share  a cornercorner with one O(6)Ca2DySb tetrahedra, corners with three equivalent O(4)Ca2DySb tetrahedra, corners with three equivalent O(5)CaDy2Sb trigonal pyramids, corners with three equivalent O(7)CaDy2Sb trigonal pyramids,  an edgeedge with one O(4)Ca2DySb tetrahedra,  an edgeedge with one O(6)Ca2DySb tetrahedra, and  an edgeedge with one O(7)CaDy2Sb trigonal pyramid. In the sixth O site, O(6) is bonded to one Ca(1), one Ca(2), one Dy(2), and one Sb(3) atom to form distorted OCa2DySb tetrahedra that share corners with three equivalent O(4)Ca2DySb tetrahedra, corners with three equivalent O(6)Ca2DySb tetrahedra,  a cornercorner with one O(5)CaDy2Sb trigonal pyramid, corners with three equivalent O(7)CaDy2Sb trigonal pyramids,  an edgeedge with one O(4)Ca2DySb tetrahedra,  an edgeedge with one O(5)CaDy2Sb trigonal pyramid, and  an edgeedge with one O(7)CaDy2Sb trigonal pyramid. In the seventh O site, O(7) is bonded to one Ca(1), one Dy(1), one Dy(2), and one Sb(3) atom to form distorted OCaDy2Sb trigonal pyramids that share  a cornercorner with one O(4)Ca2DySb tetrahedra, corners with three equivalent O(6)Ca2DySb tetrahedra, corners with three equivalent O(5)CaDy2Sb trigonal pyramids, corners with three equivalent O(7)CaDy2Sb trigonal pyramids,  an edgeedge with one O(4)Ca2DySb tetrahedra,  an edgeedge with one O(6)Ca2DySb tetrahedra, and  an edgeedge with one O(5)CaDy2Sb trigonal pyramid.
Ca2Dy3Sb3O14 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a body-centered cubic geometry to two equivalent O(4), two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms. Both Ca(1)-O(4) bond lengths are 2.62 Å. Both Ca(1)-O(5) bond lengths are 2.70 Å. Both Ca(1)-O(6) bond lengths are 2.54 Å. Both Ca(1)-O(7) bond lengths are 2.82 Å. In the second Ca site, Ca(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(4) and two equivalent O(6) atoms. Both Ca(2)-O(4) bond lengths are 2.37 Å. Both Ca(2)-O(6) bond lengths are 2.39 Å. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(5), and two equivalent O(7) atoms. Both Dy(1)-O(2) bond lengths are 2.65 Å. Both Dy(1)-O(3) bond lengths are 2.52 Å. Both Dy(1)-O(5) bond lengths are 2.23 Å. Both Dy(1)-O(7) bond lengths are 2.33 Å. In the second Dy site, Dy(2) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted DyO6 octahedra that share  a cornercorner with one Sb(2)O6 octahedra, corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(3)O6 octahedra, and  an edgeedge with one Sb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-62°. The Dy(2)-O(1) bond length is 2.32 Å. The Dy(2)-O(3) bond length is 2.25 Å. The Dy(2)-O(4) bond length is 2.27 Å. The Dy(2)-O(5) bond length is 2.34 Å. The Dy(2)-O(6) bond length is 2.28 Å. The Dy(2)-O(7) bond length is 2.24 Å. There are three inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form SbO6 octahedra that share corners with two equivalent Sb(2)O6 octahedra, corners with two equivalent Sb(3)O6 octahedra, and corners with four equivalent Dy(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-59°. Both Sb(1)-O(1) bond lengths are 2.01 Å. Both Sb(1)-O(2) bond lengths are 1.98 Å. Both Sb(1)-O(3) bond lengths are 2.00 Å. In the second Sb site, Sb(2) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form SbO6 octahedra that share corners with two equivalent Dy(2)O6 octahedra, corners with two equivalent Sb(1)O6 octahedra, and edges with two equivalent Dy(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-62°. Both Sb(2)-O(1) bond lengths are 2.05 Å. Both Sb(2)-O(4) bond lengths are 2.02 Å. Both Sb(2)-O(5) bond lengths are 1.98 Å. In the third Sb site, Sb(3) is bonded to two equivalent O(2), two equivalent O(6), and two equivalent O(7) atoms to form SbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra and corners with four equivalent Dy(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-50°. Both Sb(3)-O(2) bond lengths are 1.99 Å. Both Sb(3)-O(6) bond lengths are 2.02 Å. Both Sb(3)-O(7) bond lengths are 2.02 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Dy(2), one Sb(1), and one Sb(2) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Dy(1), one Sb(1), and one Sb(3) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Dy(1), one Dy(2), and one Sb(1) atom. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), one Dy(2), and one Sb(2) atom to form distorted OCa2DySb tetrahedra that share corners with three equivalent O(4)Ca2DySb tetrahedra, corners with three equivalent O(6)Ca2DySb tetrahedra,  a cornercorner with one O(7)CaDy2Sb trigonal pyramid, corners with three equivalent O(5)CaDy2Sb trigonal pyramids,  an edgeedge with one O(6)Ca2DySb tetrahedra,  an edgeedge with one O(5)CaDy2Sb trigonal pyramid, and  an edgeedge with one O(7)CaDy2Sb trigonal pyramid. In the fifth O site, O(5) is bonded to one Ca(1), one Dy(1), one Dy(2), and one Sb(2) atom to form distorted OCaDy2Sb trigonal pyramids that share  a cornercorner with one O(6)Ca2DySb tetrahedra, corners with three equivalent O(4)Ca2DySb tetrahedra, corners with three equivalent O(5)CaDy2Sb trigonal pyramids, corners with three equivalent O(7)CaDy2Sb trigonal pyramids,  an edgeedge with one O(4)Ca2DySb tetrahedra,  an edgeedge with one O(6)Ca2DySb tetrahedra, and  an edgeedge with one O(7)CaDy2Sb trigonal pyramid. In the sixth O site, O(6) is bonded to one Ca(1), one Ca(2), one Dy(2), and one Sb(3) atom to form distorted OCa2DySb tetrahedra that share corners with three equivalent O(4)Ca2DySb tetrahedra, corners with three equivalent O(6)Ca2DySb tetrahedra,  a cornercorner with one O(5)CaDy2Sb trigonal pyramid, corners with three equivalent O(7)CaDy2Sb trigonal pyramids,  an edgeedge with one O(4)Ca2DySb tetrahedra,  an edgeedge with one O(5)CaDy2Sb trigonal pyramid, and  an edgeedge with one O(7)CaDy2Sb trigonal pyramid. In the seventh O site, O(7) is bonded to one Ca(1), one Dy(1), one Dy(2), and one Sb(3) atom to form distorted OCaDy2Sb trigonal pyramids that share  a cornercorner with one O(4)Ca2DySb tetrahedra, corners with three equivalent O(6)Ca2DySb tetrahedra, corners with three equivalent O(5)CaDy2Sb trigonal pyramids, corners with three equivalent O(7)CaDy2Sb trigonal pyramids,  an edgeedge with one O(4)Ca2DySb tetrahedra,  an edgeedge with one O(6)Ca2DySb tetrahedra, and  an edgeedge with one O(5)CaDy2Sb trigonal pyramid.