CaY4(BiO3)4 crystallizes in the monoclinic Pm space group. Ca(1) is bonded in a distorted rectangular see-saw-like geometry to one O(5), one O(7), and two equivalent O(1) atoms. There are four inequivalent Y sites. In the first Y site, Y(1) is bonded to one O(6), one O(8), and two equivalent O(2) atoms to form distorted YO4 trigonal pyramids that share corners with four equivalent Bi(1)O6 octahedra, corners with two equivalent Y(4)O6 pentagonal pyramids, and corners with two equivalent Y(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 65-78°. In the second Y site, Y(2) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(1), and two equivalent O(3) atoms. In the third Y site, Y(3) is bonded to one O(6), one O(8), and two equivalent O(4) atoms to form distorted YO4 tetrahedra that share corners with four equivalent Bi(1)O6 octahedra and corners with two equivalent Y(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles range from 62-82°. In the fourth Y site, Y(4) is bonded to one O(5), one O(7), two equivalent O(2), and two equivalent O(3) atoms to form distorted YO6 pentagonal pyramids that share corners with two equivalent Bi(1)O6 octahedra, corners with two equivalent Y(1)O4 trigonal pyramids, and edges with two equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form distorted BiO6 octahedra that share corners with two equivalent Bi(1)O6 octahedra,  a cornercorner with one Y(4)O6 pentagonal pyramid, corners with two equivalent Y(3)O4 tetrahedra, corners with two equivalent Y(1)O4 trigonal pyramids, and  an edgeedge with one Y(4)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 58-70°. In the second Bi site, Bi(2) is bonded in a 4-coordinate geometry to one O(2), one O(4), one O(6), and one O(7) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Ca(1), one Y(2), and one Bi(1) atom. In the second O site, O(2) is bonded to one Y(1), one Y(4), one Bi(1), and one Bi(2) atom to form distorted OY2Bi2 tetrahedra that share corners with two equivalent O(2)Y2Bi2 tetrahedra, corners with two equivalent O(8)Y2Bi2 tetrahedra, and  an edgeedge with one O(5)CaYBi2 trigonal pyramid. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Y(2), one Y(4), and one Bi(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Y(3), one Bi(1), and one Bi(2) atom. In the fifth O site, O(5) is bonded to one Ca(1), one Y(4), and two equivalent Bi(1) atoms to form a mixture of corner and edge-sharing OCaYBi2 trigonal pyramids. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Y(1), one Y(3), and two equivalent Bi(2) atoms. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ca(1), one Y(2), one Y(4), and two equivalent Bi(2) atoms. In the eighth O site, O(8) is bonded to one Y(1), one Y(3), and two equivalent Bi(1) atoms to form distorted OY2Bi2 tetrahedra that share corners with four equivalent O(2)Y2Bi2 tetrahedra and corners with two equivalent O(5)CaYBi2 trigonal pyramids.
CaY4(BiO3)4 crystallizes in the monoclinic Pm space group. Ca(1) is bonded in a distorted rectangular see-saw-like geometry to one O(5), one O(7), and two equivalent O(1) atoms. The Ca(1)-O(5) bond length is 2.33 Å. The Ca(1)-O(7) bond length is 2.36 Å. Both Ca(1)-O(1) bond lengths are 2.29 Å. There are four inequivalent Y sites. In the first Y site, Y(1) is bonded to one O(6), one O(8), and two equivalent O(2) atoms to form distorted YO4 trigonal pyramids that share corners with four equivalent Bi(1)O6 octahedra, corners with two equivalent Y(4)O6 pentagonal pyramids, and corners with two equivalent Y(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 65-78°. The Y(1)-O(6) bond length is 2.12 Å. The Y(1)-O(8) bond length is 2.24 Å. Both Y(1)-O(2) bond lengths are 2.27 Å. In the second Y site, Y(2) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(1), and two equivalent O(3) atoms. The Y(2)-O(7) bond length is 2.27 Å. Both Y(2)-O(1) bond lengths are 2.31 Å. Both Y(2)-O(3) bond lengths are 2.23 Å. In the third Y site, Y(3) is bonded to one O(6), one O(8), and two equivalent O(4) atoms to form distorted YO4 tetrahedra that share corners with four equivalent Bi(1)O6 octahedra and corners with two equivalent Y(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles range from 62-82°. The Y(3)-O(6) bond length is 2.18 Å. The Y(3)-O(8) bond length is 2.16 Å. Both Y(3)-O(4) bond lengths are 2.25 Å. In the fourth Y site, Y(4) is bonded to one O(5), one O(7), two equivalent O(2), and two equivalent O(3) atoms to form distorted YO6 pentagonal pyramids that share corners with two equivalent Bi(1)O6 octahedra, corners with two equivalent Y(1)O4 trigonal pyramids, and edges with two equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. The Y(4)-O(5) bond length is 2.46 Å. The Y(4)-O(7) bond length is 2.16 Å. Both Y(4)-O(2) bond lengths are 2.53 Å. Both Y(4)-O(3) bond lengths are 2.31 Å. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form distorted BiO6 octahedra that share corners with two equivalent Bi(1)O6 octahedra,  a cornercorner with one Y(4)O6 pentagonal pyramid, corners with two equivalent Y(3)O4 tetrahedra, corners with two equivalent Y(1)O4 trigonal pyramids, and  an edgeedge with one Y(4)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 58-70°. The Bi(1)-O(1) bond length is 2.22 Å. The Bi(1)-O(2) bond length is 2.61 Å. The Bi(1)-O(3) bond length is 2.26 Å. The Bi(1)-O(4) bond length is 2.60 Å. The Bi(1)-O(5) bond length is 2.33 Å. The Bi(1)-O(8) bond length is 2.64 Å. In the second Bi site, Bi(2) is bonded in a 4-coordinate geometry to one O(2), one O(4), one O(6), and one O(7) atom. The Bi(2)-O(2) bond length is 2.20 Å. The Bi(2)-O(4) bond length is 2.20 Å. The Bi(2)-O(6) bond length is 2.65 Å. The Bi(2)-O(7) bond length is 2.73 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Ca(1), one Y(2), and one Bi(1) atom. In the second O site, O(2) is bonded to one Y(1), one Y(4), one Bi(1), and one Bi(2) atom to form distorted OY2Bi2 tetrahedra that share corners with two equivalent O(2)Y2Bi2 tetrahedra, corners with two equivalent O(8)Y2Bi2 tetrahedra, and  an edgeedge with one O(5)CaYBi2 trigonal pyramid. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Y(2), one Y(4), and one Bi(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Y(3), one Bi(1), and one Bi(2) atom. In the fifth O site, O(5) is bonded to one Ca(1), one Y(4), and two equivalent Bi(1) atoms to form a mixture of corner and edge-sharing OCaYBi2 trigonal pyramids. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Y(1), one Y(3), and two equivalent Bi(2) atoms. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ca(1), one Y(2), one Y(4), and two equivalent Bi(2) atoms. In the eighth O site, O(8) is bonded to one Y(1), one Y(3), and two equivalent Bi(1) atoms to form distorted OY2Bi2 tetrahedra that share corners with four equivalent O(2)Y2Bi2 tetrahedra and corners with two equivalent O(5)CaYBi2 trigonal pyramids.