The structure described by Gd3(BiO4)2 crystallizes in the monoclinic Cm space group. There are three inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(8), and two equivalent O(3) atoms. In the second Gd site, Gd(2) is bonded to one O(3), one O(5), one O(7), two equivalent O(4), and two equivalent O(6) atoms to form distorted GdO7 hexagonal pyramids that share  a cornercorner with one Bi(2)O6 octahedra, edges with two equivalent Gd(2)O7 hexagonal pyramids, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 51°. In the third Gd site, Gd(3) is bonded to one O(2), one O(6), one O(8), two equivalent O(1), and two equivalent O(7) atoms to form distorted GdO7 pentagonal bipyramids that share  a cornercorner with one Bi(2)O6 octahedra, edges with two equivalent Gd(2)O7 hexagonal pyramids, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 52°. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms. In the second Bi site, Bi(2) is bonded to one O(6), one O(7), two equivalent O(5), and two equivalent O(8) atoms to form distorted BiO6 octahedra that share  a cornercorner with one Gd(2)O7 hexagonal pyramid,  a cornercorner with one Gd(3)O7 pentagonal bipyramid, edges with two equivalent Gd(2)O7 hexagonal pyramids, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Gd(1), two equivalent Gd(3), and one Bi(1) atom to form distorted OGd3Bi trigonal pyramids that share  a cornercorner with one O(2)Gd2Bi2 tetrahedra,  a cornercorner with one O(5)GdBi3 tetrahedra, corners with two equivalent O(6)Gd3Bi tetrahedra, corners with two equivalent O(7)Gd3Bi tetrahedra, corners with three equivalent O(8)Gd2Bi2 tetrahedra, corners with three equivalent O(3)Gd3Bi tetrahedra, corners with two equivalent O(1)Gd3Bi trigonal pyramids,  an edgeedge with one O(7)Gd3Bi tetrahedra, edges with two equivalent O(2)Gd2Bi2 tetrahedra, and  an edgeedge with one O(4)Gd3Bi trigonal pyramid. In the second O site, O(2) is bonded to one Gd(1), one Gd(3), and two equivalent Bi(1) atoms to form OGd2Bi2 tetrahedra that share  a cornercorner with one O(6)Gd3Bi tetrahedra, corners with two equivalent O(2)Gd2Bi2 tetrahedra, corners with two equivalent O(7)Gd3Bi tetrahedra, corners with two equivalent O(5)GdBi3 tetrahedra,  a cornercorner with one O(1)Gd3Bi trigonal pyramid, corners with three equivalent O(4)Gd3Bi trigonal pyramids,  an edgeedge with one O(8)Gd2Bi2 tetrahedra, edges with two equivalent O(3)Gd3Bi tetrahedra, and edges with two equivalent O(1)Gd3Bi trigonal pyramids. In the third O site, O(3) is bonded to one Gd(2), two equivalent Gd(1), and one Bi(1) atom to form distorted OGd3Bi tetrahedra that share  a cornercorner with one O(7)Gd3Bi tetrahedra, corners with two equivalent O(8)Gd2Bi2 tetrahedra, corners with two equivalent O(3)Gd3Bi tetrahedra, corners with two equivalent O(6)Gd3Bi tetrahedra,  a cornercorner with one O(4)Gd3Bi trigonal pyramid, corners with three equivalent O(1)Gd3Bi trigonal pyramids,  an edgeedge with one O(5)GdBi3 tetrahedra, edges with two equivalent O(2)Gd2Bi2 tetrahedra, and edges with two equivalent O(4)Gd3Bi trigonal pyramids. In the fourth O site, O(4) is bonded to one Gd(1), two equivalent Gd(2), and one Bi(1) atom to form OGd3Bi trigonal pyramids that share  a cornercorner with one O(8)Gd2Bi2 tetrahedra,  a cornercorner with one O(3)Gd3Bi tetrahedra, corners with two equivalent O(6)Gd3Bi tetrahedra, corners with two equivalent O(7)Gd3Bi tetrahedra, corners with three equivalent O(2)Gd2Bi2 tetrahedra, corners with three equivalent O(5)GdBi3 tetrahedra, corners with two equivalent O(4)Gd3Bi trigonal pyramids,  an edgeedge with one O(6)Gd3Bi tetrahedra, edges with two equivalent O(3)Gd3Bi tetrahedra, and  an edgeedge with one O(1)Gd3Bi trigonal pyramid. In the fifth O site, O(5) is bonded to one Gd(2), one Bi(1), and two equivalent Bi(2) atoms to form OGdBi3 tetrahedra that share corners with two equivalent O(2)Gd2Bi2 tetrahedra, corners with two equivalent O(8)Gd2Bi2 tetrahedra, corners with two equivalent O(5)GdBi3 tetrahedra, corners with three equivalent O(7)Gd3Bi tetrahedra,  a cornercorner with one O(1)Gd3Bi trigonal pyramid, corners with three equivalent O(4)Gd3Bi trigonal pyramids,  an edgeedge with one O(8)Gd2Bi2 tetrahedra,  an edgeedge with one O(3)Gd3Bi tetrahedra, and edges with two equivalent O(6)Gd3Bi tetrahedra. In the sixth O site, O(6) is bonded to one Gd(3), two equivalent Gd(2), and one Bi(2) atom to form OGd3Bi tetrahedra that share  a cornercorner with one O(2)Gd2Bi2 tetrahedra,  a cornercorner with one O(7)Gd3Bi tetrahedra, corners with two equivalent O(3)Gd3Bi tetrahedra, corners with two equivalent O(6)Gd3Bi tetrahedra, corners with three equivalent O(8)Gd2Bi2 tetrahedra, corners with two equivalent O(1)Gd3Bi trigonal pyramids, corners with two equivalent O(4)Gd3Bi trigonal pyramids, edges with two equivalent O(7)Gd3Bi tetrahedra, edges with two equivalent O(5)GdBi3 tetrahedra, and  an edgeedge with one O(4)Gd3Bi trigonal pyramid. In the seventh O site, O(7) is bonded to one Gd(2), two equivalent Gd(3), and one Bi(2) atom to form OGd3Bi tetrahedra that share  a cornercorner with one O(3)Gd3Bi tetrahedra,  a cornercorner with one O(6)Gd3Bi tetrahedra, corners with two equivalent O(2)Gd2Bi2 tetrahedra, corners with two equivalent O(7)Gd3Bi tetrahedra, corners with three equivalent O(5)GdBi3 tetrahedra, corners with two equivalent O(1)Gd3Bi trigonal pyramids, corners with two equivalent O(4)Gd3Bi trigonal pyramids, edges with two equivalent O(8)Gd2Bi2 tetrahedra, edges with two equivalent O(6)Gd3Bi tetrahedra, and  an edgeedge with one O(1)Gd3Bi trigonal pyramid. In the eighth O site, O(8) is bonded to one Gd(1), one Gd(3), and two equivalent Bi(2) atoms to form OGd2Bi2 tetrahedra that share corners with two equivalent O(8)Gd2Bi2 tetrahedra, corners with two equivalent O(3)Gd3Bi tetrahedra, corners with two equivalent O(5)GdBi3 tetrahedra, corners with three equivalent O(6)Gd3Bi tetrahedra,  a cornercorner with one O(4)Gd3Bi trigonal pyramid, corners with three equivalent O(1)Gd3Bi trigonal pyramids,  an edgeedge with one O(2)Gd2Bi2 tetrahedra,  an edgeedge with one O(5)GdBi3 tetrahedra, and edges with two equivalent O(7)Gd3Bi tetrahedra. is represented by the CIF file [CIF]
data_Gd3(BiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.858
_cell_length_b   6.858
_cell_length_c   9.635
_cell_angle_alpha   61.282
_cell_angle_beta   61.282
_cell_angle_gamma   32.152
_symmetry_Int_Tables_number   1
_cell_volume   208.801
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Gd  Gd0  1  0.192  0.192  0.231  1.0
  Gd  Gd1  1  0.578  0.578  0.609  1.0
  Gd  Gd2  1  0.023  0.023  0.986  1.0
  Bi  Bi3  1  0.404  0.404  0.369  1.0
  Bi  Bi4  1  0.800  0.800  0.802  1.0
  O  O5  1  0.396  0.396  0.123  1.0
  O  O6  1  0.995  0.995  0.250  1.0
  O  O7  1  0.611  0.611  0.343  1.0
  O  O8  1  0.199  0.199  0.480  1.0
  O  O9  1  0.385  0.385  0.633  1.0
  O  O10  1  0.976  0.976  0.781  1.0
  O  O11  1  0.623  0.623  0.819  1.0
  O  O12  1  0.212  0.212  0.975  1.0
[/CIF]
.
The structure described by Gd3(BiO4)2 crystallizes in the monoclinic Cm space group. There are three inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(8), and two equivalent O(3) atoms. In the second Gd site, Gd(2) is bonded to one O(3), one O(5), one O(7), two equivalent O(4), and two equivalent O(6) atoms to form distorted GdO7 hexagonal pyramids that share  a cornercorner with one Bi(2)O6 octahedra, edges with two equivalent Gd(2)O7 hexagonal pyramids, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 51°. In the third Gd site, Gd(3) is bonded to one O(2), one O(6), one O(8), two equivalent O(1), and two equivalent O(7) atoms to form distorted GdO7 pentagonal bipyramids that share  a cornercorner with one Bi(2)O6 octahedra, edges with two equivalent Gd(2)O7 hexagonal pyramids, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 52°. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms. In the second Bi site, Bi(2) is bonded to one O(6), one O(7), two equivalent O(5), and two equivalent O(8) atoms to form distorted BiO6 octahedra that share  a cornercorner with one Gd(2)O7 hexagonal pyramid,  a cornercorner with one Gd(3)O7 pentagonal bipyramid, edges with two equivalent Gd(2)O7 hexagonal pyramids, edges with two equivalent Bi(2)O6 octahedra, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Gd(1), two equivalent Gd(3), and one Bi(1) atom to form distorted OGd3Bi trigonal pyramids that share  a cornercorner with one O(2)Gd2Bi2 tetrahedra,  a cornercorner with one O(5)GdBi3 tetrahedra, corners with two equivalent O(6)Gd3Bi tetrahedra, corners with two equivalent O(7)Gd3Bi tetrahedra, corners with three equivalent O(8)Gd2Bi2 tetrahedra, corners with three equivalent O(3)Gd3Bi tetrahedra, corners with two equivalent O(1)Gd3Bi trigonal pyramids,  an edgeedge with one O(7)Gd3Bi tetrahedra, edges with two equivalent O(2)Gd2Bi2 tetrahedra, and  an edgeedge with one O(4)Gd3Bi trigonal pyramid. In the second O site, O(2) is bonded to one Gd(1), one Gd(3), and two equivalent Bi(1) atoms to form OGd2Bi2 tetrahedra that share  a cornercorner with one O(6)Gd3Bi tetrahedra, corners with two equivalent O(2)Gd2Bi2 tetrahedra, corners with two equivalent O(7)Gd3Bi tetrahedra, corners with two equivalent O(5)GdBi3 tetrahedra,  a cornercorner with one O(1)Gd3Bi trigonal pyramid, corners with three equivalent O(4)Gd3Bi trigonal pyramids,  an edgeedge with one O(8)Gd2Bi2 tetrahedra, edges with two equivalent O(3)Gd3Bi tetrahedra, and edges with two equivalent O(1)Gd3Bi trigonal pyramids. In the third O site, O(3) is bonded to one Gd(2), two equivalent Gd(1), and one Bi(1) atom to form distorted OGd3Bi tetrahedra that share  a cornercorner with one O(7)Gd3Bi tetrahedra, corners with two equivalent O(8)Gd2Bi2 tetrahedra, corners with two equivalent O(3)Gd3Bi tetrahedra, corners with two equivalent O(6)Gd3Bi tetrahedra,  a cornercorner with one O(4)Gd3Bi trigonal pyramid, corners with three equivalent O(1)Gd3Bi trigonal pyramids,  an edgeedge with one O(5)GdBi3 tetrahedra, edges with two equivalent O(2)Gd2Bi2 tetrahedra, and edges with two equivalent O(4)Gd3Bi trigonal pyramids. In the fourth O site, O(4) is bonded to one Gd(1), two equivalent Gd(2), and one Bi(1) atom to form OGd3Bi trigonal pyramids that share  a cornercorner with one O(8)Gd2Bi2 tetrahedra,  a cornercorner with one O(3)Gd3Bi tetrahedra, corners with two equivalent O(6)Gd3Bi tetrahedra, corners with two equivalent O(7)Gd3Bi tetrahedra, corners with three equivalent O(2)Gd2Bi2 tetrahedra, corners with three equivalent O(5)GdBi3 tetrahedra, corners with two equivalent O(4)Gd3Bi trigonal pyramids,  an edgeedge with one O(6)Gd3Bi tetrahedra, edges with two equivalent O(3)Gd3Bi tetrahedra, and  an edgeedge with one O(1)Gd3Bi trigonal pyramid. In the fifth O site, O(5) is bonded to one Gd(2), one Bi(1), and two equivalent Bi(2) atoms to form OGdBi3 tetrahedra that share corners with two equivalent O(2)Gd2Bi2 tetrahedra, corners with two equivalent O(8)Gd2Bi2 tetrahedra, corners with two equivalent O(5)GdBi3 tetrahedra, corners with three equivalent O(7)Gd3Bi tetrahedra,  a cornercorner with one O(1)Gd3Bi trigonal pyramid, corners with three equivalent O(4)Gd3Bi trigonal pyramids,  an edgeedge with one O(8)Gd2Bi2 tetrahedra,  an edgeedge with one O(3)Gd3Bi tetrahedra, and edges with two equivalent O(6)Gd3Bi tetrahedra. In the sixth O site, O(6) is bonded to one Gd(3), two equivalent Gd(2), and one Bi(2) atom to form OGd3Bi tetrahedra that share  a cornercorner with one O(2)Gd2Bi2 tetrahedra,  a cornercorner with one O(7)Gd3Bi tetrahedra, corners with two equivalent O(3)Gd3Bi tetrahedra, corners with two equivalent O(6)Gd3Bi tetrahedra, corners with three equivalent O(8)Gd2Bi2 tetrahedra, corners with two equivalent O(1)Gd3Bi trigonal pyramids, corners with two equivalent O(4)Gd3Bi trigonal pyramids, edges with two equivalent O(7)Gd3Bi tetrahedra, edges with two equivalent O(5)GdBi3 tetrahedra, and  an edgeedge with one O(4)Gd3Bi trigonal pyramid. In the seventh O site, O(7) is bonded to one Gd(2), two equivalent Gd(3), and one Bi(2) atom to form OGd3Bi tetrahedra that share  a cornercorner with one O(3)Gd3Bi tetrahedra,  a cornercorner with one O(6)Gd3Bi tetrahedra, corners with two equivalent O(2)Gd2Bi2 tetrahedra, corners with two equivalent O(7)Gd3Bi tetrahedra, corners with three equivalent O(5)GdBi3 tetrahedra, corners with two equivalent O(1)Gd3Bi trigonal pyramids, corners with two equivalent O(4)Gd3Bi trigonal pyramids, edges with two equivalent O(8)Gd2Bi2 tetrahedra, edges with two equivalent O(6)Gd3Bi tetrahedra, and  an edgeedge with one O(1)Gd3Bi trigonal pyramid. In the eighth O site, O(8) is bonded to one Gd(1), one Gd(3), and two equivalent Bi(2) atoms to form OGd2Bi2 tetrahedra that share corners with two equivalent O(8)Gd2Bi2 tetrahedra, corners with two equivalent O(3)Gd3Bi tetrahedra, corners with two equivalent O(5)GdBi3 tetrahedra, corners with three equivalent O(6)Gd3Bi tetrahedra,  a cornercorner with one O(4)Gd3Bi trigonal pyramid, corners with three equivalent O(1)Gd3Bi trigonal pyramids,  an edgeedge with one O(2)Gd2Bi2 tetrahedra,  an edgeedge with one O(5)GdBi3 tetrahedra, and edges with two equivalent O(7)Gd3Bi tetrahedra. is represented by the CIF file [CIF]
data_Gd3(BiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.858
_cell_length_b   6.858
_cell_length_c   9.635
_cell_angle_alpha   61.282
_cell_angle_beta   61.282
_cell_angle_gamma   32.152
_symmetry_Int_Tables_number   1
_cell_volume   208.801
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Gd  Gd0  1  0.192  0.192  0.231  1.0
  Gd  Gd1  1  0.578  0.578  0.609  1.0
  Gd  Gd2  1  0.023  0.023  0.986  1.0
  Bi  Bi3  1  0.404  0.404  0.369  1.0
  Bi  Bi4  1  0.800  0.800  0.802  1.0
  O  O5  1  0.396  0.396  0.123  1.0
  O  O6  1  0.995  0.995  0.250  1.0
  O  O7  1  0.611  0.611  0.343  1.0
  O  O8  1  0.199  0.199  0.480  1.0
  O  O9  1  0.385  0.385  0.633  1.0
  O  O10  1  0.976  0.976  0.781  1.0
  O  O11  1  0.623  0.623  0.819  1.0
  O  O12  1  0.212  0.212  0.975  1.0
[/CIF]
.