Ca3La2Sb3O14 crystallizes in the monoclinic C2/m space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms. In the second Ca site, Ca(2) is bonded to two equivalent O(1), two equivalent O(3), and four equivalent O(5) atoms to form CaO8 hexagonal bipyramids that share edges with two equivalent Sb(2)O6 octahedra and edges with four equivalent Sb(1)O6 octahedra. In the third Ca site, Ca(3) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Sb(2)O6 octahedra and corners with four equivalent Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-57°. La(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. There are two 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(5) atoms to form SbO6 octahedra that share corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O6 octahedra, and edges with two equivalent Ca(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 40-56°. In the second Sb site, Sb(2) is bonded to two equivalent O(4) and four equivalent O(5) atoms to form SbO6 octahedra that share corners with two equivalent Ca(3)O6 octahedra, corners with four equivalent Sb(1)O6 octahedra, and edges with two equivalent Ca(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-57°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), and two equivalent Sb(1) atoms. In the second O site, O(2) is bonded to one Ca(1), one Ca(3), one La(1), and one Sb(1) atom to form distorted OCa2LaSb tetrahedra that share corners with two equivalent O(3)Ca2La2 tetrahedra, corners with two equivalent O(4)CaLa2Sb tetrahedra, corners with six equivalent O(2)Ca2LaSb tetrahedra,  an edgeedge with one O(3)Ca2La2 tetrahedra,  an edgeedge with one O(2)Ca2LaSb tetrahedra, and  an edgeedge with one O(4)CaLa2Sb tetrahedra. In the third O site, O(3) is bonded to one Ca(1), one Ca(2), and two equivalent La(1) atoms to form OCa2La2 tetrahedra that share corners with two equivalent O(4)CaLa2Sb tetrahedra, corners with four equivalent O(3)Ca2La2 tetrahedra, corners with four equivalent O(2)Ca2LaSb tetrahedra,  an edgeedge with one O(4)CaLa2Sb tetrahedra, and edges with two equivalent O(2)Ca2LaSb tetrahedra. In the fourth O site, O(4) is bonded to one Ca(3), two equivalent La(1), and one Sb(2) atom to form distorted OCaLa2Sb tetrahedra that share corners with two equivalent O(3)Ca2La2 tetrahedra, corners with four equivalent O(2)Ca2LaSb tetrahedra, corners with four equivalent O(4)CaLa2Sb tetrahedra,  an edgeedge with one O(3)Ca2La2 tetrahedra, and edges with two equivalent O(2)Ca2LaSb tetrahedra. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(2), one La(1), one Sb(1), and one Sb(2) atom.
Ca3La2Sb3O14 crystallizes in the monoclinic C2/m space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms. Both Ca(1)-O(1) bond lengths are 2.87 Å. Both Ca(1)-O(3) bond lengths are 2.35 Å. All Ca(1)-O(2) bond lengths are 2.56 Å. In the second Ca site, Ca(2) is bonded to two equivalent O(1), two equivalent O(3), and four equivalent O(5) atoms to form CaO8 hexagonal bipyramids that share edges with two equivalent Sb(2)O6 octahedra and edges with four equivalent Sb(1)O6 octahedra. Both Ca(2)-O(1) bond lengths are 2.65 Å. Both Ca(2)-O(3) bond lengths are 2.27 Å. All Ca(2)-O(5) bond lengths are 2.63 Å. In the third Ca site, Ca(3) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Sb(2)O6 octahedra and corners with four equivalent Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-57°. Both Ca(3)-O(4) bond lengths are 2.31 Å. All Ca(3)-O(2) bond lengths are 2.33 Å. La(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. Both La(1)-O(2) bond lengths are 2.54 Å. Both La(1)-O(3) bond lengths are 2.34 Å. Both La(1)-O(4) bond lengths are 2.55 Å. Both La(1)-O(5) bond lengths are 2.83 Å. There are two 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(5) atoms to form SbO6 octahedra that share corners with two equivalent Ca(3)O6 octahedra, corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O6 octahedra, and edges with two equivalent Ca(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 40-56°. Both Sb(1)-O(1) bond lengths are 2.03 Å. Both Sb(1)-O(2) bond lengths are 1.96 Å. Both Sb(1)-O(5) bond lengths are 2.04 Å. In the second Sb site, Sb(2) is bonded to two equivalent O(4) and four equivalent O(5) atoms to form SbO6 octahedra that share corners with two equivalent Ca(3)O6 octahedra, corners with four equivalent Sb(1)O6 octahedra, and edges with two equivalent Ca(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-57°. Both Sb(2)-O(4) bond lengths are 1.97 Å. All Sb(2)-O(5) bond lengths are 2.04 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), and two equivalent Sb(1) atoms. In the second O site, O(2) is bonded to one Ca(1), one Ca(3), one La(1), and one Sb(1) atom to form distorted OCa2LaSb tetrahedra that share corners with two equivalent O(3)Ca2La2 tetrahedra, corners with two equivalent O(4)CaLa2Sb tetrahedra, corners with six equivalent O(2)Ca2LaSb tetrahedra,  an edgeedge with one O(3)Ca2La2 tetrahedra,  an edgeedge with one O(2)Ca2LaSb tetrahedra, and  an edgeedge with one O(4)CaLa2Sb tetrahedra. In the third O site, O(3) is bonded to one Ca(1), one Ca(2), and two equivalent La(1) atoms to form OCa2La2 tetrahedra that share corners with two equivalent O(4)CaLa2Sb tetrahedra, corners with four equivalent O(3)Ca2La2 tetrahedra, corners with four equivalent O(2)Ca2LaSb tetrahedra,  an edgeedge with one O(4)CaLa2Sb tetrahedra, and edges with two equivalent O(2)Ca2LaSb tetrahedra. In the fourth O site, O(4) is bonded to one Ca(3), two equivalent La(1), and one Sb(2) atom to form distorted OCaLa2Sb tetrahedra that share corners with two equivalent O(3)Ca2La2 tetrahedra, corners with four equivalent O(2)Ca2LaSb tetrahedra, corners with four equivalent O(4)CaLa2Sb tetrahedra,  an edgeedge with one O(3)Ca2La2 tetrahedra, and edges with two equivalent O(2)Ca2LaSb tetrahedra. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(2), one La(1), one Sb(1), and one Sb(2) atom.