The material structure described by Ho3TaO7 crystallizes in the orthorhombic Cmme space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted corner-sharing HoO6 octahedra. The corner-sharing octahedral tilt angles are 70°. In the second Ho site, Ho(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(3), and four equivalent O(2) atoms. Ta(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ho(1) and two equivalent Ho(2) atoms to form OHo4 tetrahedra that share corners with two equivalent O(1)Ho4 tetrahedra, corners with four equivalent O(3)Ho2Ta2 tetrahedra, corners with eight equivalent O(2)Ho3Ta tetrahedra, and edges with four equivalent O(2)Ho3Ta tetrahedra. In the second O site, O(2) is bonded to one Ho(1), two equivalent Ho(2), and one Ta(1) atom to form OHo3Ta tetrahedra that share corners with two equivalent O(1)Ho4 tetrahedra, corners with four equivalent O(3)Ho2Ta2 tetrahedra, corners with eight equivalent O(2)Ho3Ta tetrahedra,  an edgeedge with one O(1)Ho4 tetrahedra, edges with two equivalent O(3)Ho2Ta2 tetrahedra, and edges with two equivalent O(2)Ho3Ta tetrahedra. In the third O site, O(3) is bonded to two equivalent Ho(2) and two equivalent Ta(1) atoms to form distorted OHo2Ta2 tetrahedra that share corners with two equivalent O(1)Ho4 tetrahedra, corners with four equivalent O(3)Ho2Ta2 tetrahedra, corners with eight equivalent O(2)Ho3Ta tetrahedra, edges with two equivalent O(3)Ho2Ta2 tetrahedra, and edges with four equivalent O(2)Ho3Ta tetrahedra. is represented by the CIF file [CIF]
data_Ho3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.106
_cell_length_b   8.106
_cell_length_c   5.357
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   125.436
_symmetry_Int_Tables_number   1
_cell_volume   286.788
_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
  Ho  Ho0  1  0.000  0.500  0.000  1.0
  Ho  Ho1  1  0.500  0.000  0.000  1.0
  Ho  Ho2  1  0.620  0.380  0.471  1.0
  Ho  Ho3  1  0.120  0.880  0.529  1.0
  Ho  Ho4  1  0.880  0.120  0.471  1.0
  Ho  Ho5  1  0.380  0.620  0.529  1.0
  Ta  Ta6  1  0.750  0.750  0.000  1.0
  Ta  Ta7  1  0.250  0.250  0.000  1.0
  O  O8  1  0.750  0.250  0.241  1.0
  O  O9  1  0.838  0.598  0.764  1.0
  O  O10  1  0.250  0.750  0.759  1.0
  O  O11  1  0.987  0.013  0.211  1.0
  O  O12  1  0.402  0.162  0.764  1.0
  O  O13  1  0.098  0.338  0.764  1.0
  O  O14  1  0.338  0.098  0.236  1.0
  O  O15  1  0.513  0.487  0.211  1.0
  O  O16  1  0.487  0.513  0.789  1.0
  O  O17  1  0.662  0.902  0.764  1.0
  O  O18  1  0.902  0.662  0.236  1.0
  O  O19  1  0.598  0.838  0.236  1.0
  O  O20  1  0.013  0.987  0.789  1.0
  O  O21  1  0.162  0.402  0.236  1.0
[/CIF]
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The material structure described by Ho3TaO7 crystallizes in the orthorhombic Cmme space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted corner-sharing HoO6 octahedra. The corner-sharing octahedral tilt angles are 70°. In the second Ho site, Ho(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(3), and four equivalent O(2) atoms. Ta(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ho(1) and two equivalent Ho(2) atoms to form OHo4 tetrahedra that share corners with two equivalent O(1)Ho4 tetrahedra, corners with four equivalent O(3)Ho2Ta2 tetrahedra, corners with eight equivalent O(2)Ho3Ta tetrahedra, and edges with four equivalent O(2)Ho3Ta tetrahedra. In the second O site, O(2) is bonded to one Ho(1), two equivalent Ho(2), and one Ta(1) atom to form OHo3Ta tetrahedra that share corners with two equivalent O(1)Ho4 tetrahedra, corners with four equivalent O(3)Ho2Ta2 tetrahedra, corners with eight equivalent O(2)Ho3Ta tetrahedra,  an edgeedge with one O(1)Ho4 tetrahedra, edges with two equivalent O(3)Ho2Ta2 tetrahedra, and edges with two equivalent O(2)Ho3Ta tetrahedra. In the third O site, O(3) is bonded to two equivalent Ho(2) and two equivalent Ta(1) atoms to form distorted OHo2Ta2 tetrahedra that share corners with two equivalent O(1)Ho4 tetrahedra, corners with four equivalent O(3)Ho2Ta2 tetrahedra, corners with eight equivalent O(2)Ho3Ta tetrahedra, edges with two equivalent O(3)Ho2Ta2 tetrahedra, and edges with four equivalent O(2)Ho3Ta tetrahedra. is represented by the CIF file [CIF]
data_Ho3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.106
_cell_length_b   8.106
_cell_length_c   5.357
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   125.436
_symmetry_Int_Tables_number   1
_cell_volume   286.788
_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
  Ho  Ho0  1  0.000  0.500  0.000  1.0
  Ho  Ho1  1  0.500  0.000  0.000  1.0
  Ho  Ho2  1  0.620  0.380  0.471  1.0
  Ho  Ho3  1  0.120  0.880  0.529  1.0
  Ho  Ho4  1  0.880  0.120  0.471  1.0
  Ho  Ho5  1  0.380  0.620  0.529  1.0
  Ta  Ta6  1  0.750  0.750  0.000  1.0
  Ta  Ta7  1  0.250  0.250  0.000  1.0
  O  O8  1  0.750  0.250  0.241  1.0
  O  O9  1  0.838  0.598  0.764  1.0
  O  O10  1  0.250  0.750  0.759  1.0
  O  O11  1  0.987  0.013  0.211  1.0
  O  O12  1  0.402  0.162  0.764  1.0
  O  O13  1  0.098  0.338  0.764  1.0
  O  O14  1  0.338  0.098  0.236  1.0
  O  O15  1  0.513  0.487  0.211  1.0
  O  O16  1  0.487  0.513  0.789  1.0
  O  O17  1  0.662  0.902  0.764  1.0
  O  O18  1  0.902  0.662  0.236  1.0
  O  O19  1  0.598  0.838  0.236  1.0
  O  O20  1  0.013  0.987  0.789  1.0
  O  O21  1  0.162  0.402  0.236  1.0
[/CIF]
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