The crystal structure described by Gd3TaO7 crystallizes in the triclinic P-1 space group. There are three inequivalent Gd sites. In the first Gd site, Gd(1) is bonded to one O(3), one O(4), one O(7), two equivalent O(2), and two equivalent O(6) atoms to form distorted GdO7 pentagonal bipyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Gd(3)O7 pentagonal bipyramid,  an edgeedge with one Ta(1)O6 octahedra, edges with two equivalent Gd(1)O7 pentagonal bipyramids, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 49-51°. In the second Gd site, Gd(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(6), two equivalent O(4), and two equivalent O(7) atoms. In the third Gd site, Gd(3) is bonded to one O(5), one O(6), one O(7), two equivalent O(1), and two equivalent O(3) atoms to form distorted GdO7 pentagonal bipyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Gd(1)O7 pentagonal bipyramid,  an edgeedge with one Ta(1)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, edges with two equivalent Gd(1)O7 pentagonal bipyramids, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 44°. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Gd(1)O7 pentagonal bipyramids, corners with two equivalent Gd(3)O7 pentagonal bipyramids, edges with two equivalent Gd(1)O7 pentagonal bipyramids, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 31°. In the second Ta site, Ta(2) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Gd(1)O7 pentagonal bipyramids, corners with two equivalent Gd(3)O7 pentagonal bipyramids, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 31°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Gd(2), two equivalent Gd(3), and one Ta(2) atom to form distorted OGd3Ta trigonal pyramids that share  a cornercorner with one O(6)Gd4 tetrahedra, corners with two equivalent O(4)Gd3Ta tetrahedra, corners with two equivalent O(7)Gd4 tetrahedra, corners with four equivalent O(3)Gd3Ta tetrahedra,  a cornercorner with one O(1)Gd3Ta trigonal pyramid,  an edgeedge with one O(4)Gd3Ta tetrahedra,  an edgeedge with one O(6)Gd4 tetrahedra,  an edgeedge with one O(7)Gd4 tetrahedra, and  an edgeedge with one O(1)Gd3Ta trigonal pyramid. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Gd(2), two equivalent Gd(1), and one Ta(1) atom. In the third O site, O(3) is bonded to one Gd(1), two equivalent Gd(3), and one Ta(1) atom to form distorted OGd3Ta tetrahedra that share  a cornercorner with one O(3)Gd3Ta tetrahedra,  a cornercorner with one O(4)Gd3Ta tetrahedra,  a cornercorner with one O(7)Gd4 tetrahedra, corners with two equivalent O(6)Gd4 tetrahedra, corners with four equivalent O(1)Gd3Ta trigonal pyramids,  an edgeedge with one O(3)Gd3Ta tetrahedra,  an edgeedge with one O(6)Gd4 tetrahedra, and  an edgeedge with one O(7)Gd4 tetrahedra. In the fourth O site, O(4) is bonded to one Gd(1), two equivalent Gd(2), and one Ta(2) atom to form distorted OGd3Ta tetrahedra that share  a cornercorner with one O(3)Gd3Ta tetrahedra,  a cornercorner with one O(4)Gd3Ta tetrahedra, corners with three equivalent O(7)Gd4 tetrahedra, corners with four equivalent O(6)Gd4 tetrahedra, corners with two equivalent O(1)Gd3Ta trigonal pyramids,  an edgeedge with one O(4)Gd3Ta tetrahedra,  an edgeedge with one O(7)Gd4 tetrahedra, and  an edgeedge with one O(1)Gd3Ta trigonal pyramid. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Gd(3), one Ta(1), and one Ta(2) atom. In the sixth O site, O(6) is bonded to one Gd(2), one Gd(3), and two equivalent Gd(1) atoms to form OGd4 tetrahedra that share corners with two equivalent O(3)Gd3Ta tetrahedra, corners with three equivalent O(7)Gd4 tetrahedra, corners with four equivalent O(4)Gd3Ta tetrahedra,  a cornercorner with one O(1)Gd3Ta trigonal pyramid,  an edgeedge with one O(3)Gd3Ta tetrahedra,  an edgeedge with one O(6)Gd4 tetrahedra,  an edgeedge with one O(7)Gd4 tetrahedra, and  an edgeedge with one O(1)Gd3Ta trigonal pyramid. In the seventh O site, O(7) is bonded to one Gd(1), one Gd(3), and two equivalent Gd(2) atoms to form OGd4 tetrahedra that share  a cornercorner with one O(3)Gd3Ta tetrahedra, corners with three equivalent O(4)Gd3Ta tetrahedra, corners with three equivalent O(6)Gd4 tetrahedra, corners with two equivalent O(1)Gd3Ta trigonal pyramids,  an edgeedge with one O(3)Gd3Ta tetrahedra,  an edgeedge with one O(4)Gd3Ta tetrahedra,  an edgeedge with one O(6)Gd4 tetrahedra,  an edgeedge with one O(7)Gd4 tetrahedra, and  an edgeedge with one O(1)Gd3Ta trigonal pyramid. is represented by the CIF file [CIF]
data_Gd3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.423
_cell_length_b   6.524
_cell_length_c   7.623
_cell_angle_alpha   106.855
_cell_angle_beta   89.845
_cell_angle_gamma   97.462
_symmetry_Int_Tables_number   1
_cell_volume   302.905
_cell_formula_units_Z   2
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  0.739  0.465  0.117  1.0
  Gd  Gd1  1  0.739  0.461  0.611  1.0
  Gd  Gd2  1  0.545  0.993  0.750  1.0
  Gd  Gd3  1  0.455  0.007  0.250  1.0
  Gd  Gd4  1  0.261  0.539  0.389  1.0
  Gd  Gd5  1  0.261  0.535  0.883  1.0
  Ta  Ta6  1  0.000  0.000  0.000  1.0
  Ta  Ta7  1  0.000  0.000  0.500  1.0
  O  O8  1  0.712  0.068  0.484  1.0
  O  O9  1  0.921  0.679  0.943  1.0
  O  O10  1  0.711  0.069  0.049  1.0
  O  O11  1  0.923  0.674  0.398  1.0
  O  O12  1  0.920  0.965  0.741  1.0
  O  O13  1  0.558  0.350  0.835  1.0
  O  O14  1  0.543  0.362  0.341  1.0
  O  O15  1  0.457  0.638  0.659  1.0
  O  O16  1  0.442  0.650  0.165  1.0
  O  O17  1  0.080  0.035  0.259  1.0
  O  O18  1  0.077  0.326  0.602  1.0
  O  O19  1  0.289  0.931  0.951  1.0
  O  O20  1  0.079  0.321  0.057  1.0
  O  O21  1  0.288  0.932  0.516  1.0
[/CIF]
.
The crystal structure described by Gd3TaO7 crystallizes in the triclinic P-1 space group. There are three inequivalent Gd sites. In the first Gd site, Gd(1) is bonded to one O(3), one O(4), one O(7), two equivalent O(2), and two equivalent O(6) atoms to form distorted GdO7 pentagonal bipyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Gd(3)O7 pentagonal bipyramid,  an edgeedge with one Ta(1)O6 octahedra, edges with two equivalent Gd(1)O7 pentagonal bipyramids, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 49-51°. In the second Gd site, Gd(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(6), two equivalent O(4), and two equivalent O(7) atoms. In the third Gd site, Gd(3) is bonded to one O(5), one O(6), one O(7), two equivalent O(1), and two equivalent O(3) atoms to form distorted GdO7 pentagonal bipyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Gd(1)O7 pentagonal bipyramid,  an edgeedge with one Ta(1)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, edges with two equivalent Gd(1)O7 pentagonal bipyramids, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 44°. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Gd(1)O7 pentagonal bipyramids, corners with two equivalent Gd(3)O7 pentagonal bipyramids, edges with two equivalent Gd(1)O7 pentagonal bipyramids, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 31°. In the second Ta site, Ta(2) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Gd(1)O7 pentagonal bipyramids, corners with two equivalent Gd(3)O7 pentagonal bipyramids, and edges with two equivalent Gd(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 31°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Gd(2), two equivalent Gd(3), and one Ta(2) atom to form distorted OGd3Ta trigonal pyramids that share  a cornercorner with one O(6)Gd4 tetrahedra, corners with two equivalent O(4)Gd3Ta tetrahedra, corners with two equivalent O(7)Gd4 tetrahedra, corners with four equivalent O(3)Gd3Ta tetrahedra,  a cornercorner with one O(1)Gd3Ta trigonal pyramid,  an edgeedge with one O(4)Gd3Ta tetrahedra,  an edgeedge with one O(6)Gd4 tetrahedra,  an edgeedge with one O(7)Gd4 tetrahedra, and  an edgeedge with one O(1)Gd3Ta trigonal pyramid. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Gd(2), two equivalent Gd(1), and one Ta(1) atom. In the third O site, O(3) is bonded to one Gd(1), two equivalent Gd(3), and one Ta(1) atom to form distorted OGd3Ta tetrahedra that share  a cornercorner with one O(3)Gd3Ta tetrahedra,  a cornercorner with one O(4)Gd3Ta tetrahedra,  a cornercorner with one O(7)Gd4 tetrahedra, corners with two equivalent O(6)Gd4 tetrahedra, corners with four equivalent O(1)Gd3Ta trigonal pyramids,  an edgeedge with one O(3)Gd3Ta tetrahedra,  an edgeedge with one O(6)Gd4 tetrahedra, and  an edgeedge with one O(7)Gd4 tetrahedra. In the fourth O site, O(4) is bonded to one Gd(1), two equivalent Gd(2), and one Ta(2) atom to form distorted OGd3Ta tetrahedra that share  a cornercorner with one O(3)Gd3Ta tetrahedra,  a cornercorner with one O(4)Gd3Ta tetrahedra, corners with three equivalent O(7)Gd4 tetrahedra, corners with four equivalent O(6)Gd4 tetrahedra, corners with two equivalent O(1)Gd3Ta trigonal pyramids,  an edgeedge with one O(4)Gd3Ta tetrahedra,  an edgeedge with one O(7)Gd4 tetrahedra, and  an edgeedge with one O(1)Gd3Ta trigonal pyramid. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Gd(3), one Ta(1), and one Ta(2) atom. In the sixth O site, O(6) is bonded to one Gd(2), one Gd(3), and two equivalent Gd(1) atoms to form OGd4 tetrahedra that share corners with two equivalent O(3)Gd3Ta tetrahedra, corners with three equivalent O(7)Gd4 tetrahedra, corners with four equivalent O(4)Gd3Ta tetrahedra,  a cornercorner with one O(1)Gd3Ta trigonal pyramid,  an edgeedge with one O(3)Gd3Ta tetrahedra,  an edgeedge with one O(6)Gd4 tetrahedra,  an edgeedge with one O(7)Gd4 tetrahedra, and  an edgeedge with one O(1)Gd3Ta trigonal pyramid. In the seventh O site, O(7) is bonded to one Gd(1), one Gd(3), and two equivalent Gd(2) atoms to form OGd4 tetrahedra that share  a cornercorner with one O(3)Gd3Ta tetrahedra, corners with three equivalent O(4)Gd3Ta tetrahedra, corners with three equivalent O(6)Gd4 tetrahedra, corners with two equivalent O(1)Gd3Ta trigonal pyramids,  an edgeedge with one O(3)Gd3Ta tetrahedra,  an edgeedge with one O(4)Gd3Ta tetrahedra,  an edgeedge with one O(6)Gd4 tetrahedra,  an edgeedge with one O(7)Gd4 tetrahedra, and  an edgeedge with one O(1)Gd3Ta trigonal pyramid. is represented by the CIF file [CIF]
data_Gd3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.423
_cell_length_b   6.524
_cell_length_c   7.623
_cell_angle_alpha   106.855
_cell_angle_beta   89.845
_cell_angle_gamma   97.462
_symmetry_Int_Tables_number   1
_cell_volume   302.905
_cell_formula_units_Z   2
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  0.739  0.465  0.117  1.0
  Gd  Gd1  1  0.739  0.461  0.611  1.0
  Gd  Gd2  1  0.545  0.993  0.750  1.0
  Gd  Gd3  1  0.455  0.007  0.250  1.0
  Gd  Gd4  1  0.261  0.539  0.389  1.0
  Gd  Gd5  1  0.261  0.535  0.883  1.0
  Ta  Ta6  1  0.000  0.000  0.000  1.0
  Ta  Ta7  1  0.000  0.000  0.500  1.0
  O  O8  1  0.712  0.068  0.484  1.0
  O  O9  1  0.921  0.679  0.943  1.0
  O  O10  1  0.711  0.069  0.049  1.0
  O  O11  1  0.923  0.674  0.398  1.0
  O  O12  1  0.920  0.965  0.741  1.0
  O  O13  1  0.558  0.350  0.835  1.0
  O  O14  1  0.543  0.362  0.341  1.0
  O  O15  1  0.457  0.638  0.659  1.0
  O  O16  1  0.442  0.650  0.165  1.0
  O  O17  1  0.080  0.035  0.259  1.0
  O  O18  1  0.077  0.326  0.602  1.0
  O  O19  1  0.289  0.931  0.951  1.0
  O  O20  1  0.079  0.321  0.057  1.0
  O  O21  1  0.288  0.932  0.516  1.0
[/CIF]
.