The crystal structure described by Ho3TaO7 crystallizes in the monoclinic Pc space group. There are three inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to one O(2), one O(4), one O(5), one O(7), and two equivalent O(1) atoms to form distorted HoO6 octahedra that share corners with two equivalent Ho(1)O6 octahedra and corners with two equivalent Ta(1)O5 tetrahedra. The corner-sharing octahedral tilt angles are 63°. In the second Ho site, Ho(2) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(6), one O(7), two equivalent O(2), and two equivalent O(4) atoms. In the third Ho site, Ho(3) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(6), two equivalent O(5), and two equivalent O(7) atoms. Ta(1) is bonded to one O(4), one O(5), one O(6), and two equivalent O(3) atoms to form distorted TaO5 tetrahedra that share corners with two equivalent Ho(1)O6 octahedra and corners with two equivalent Ta(1)O5 tetrahedra. The corner-sharing octahedral tilt angles range from 61-64°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Ho(2), one Ho(3), and two equivalent Ho(1) atoms to form corner-sharing OHo4 tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ho(1) and two equivalent Ho(2) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ho(2), one Ho(3), and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ho(1), two equivalent Ho(2), and one Ta(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ho(1), two equivalent Ho(3), and one Ta(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Ho(2), one Ho(3), and one Ta(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ho(1), one Ho(2), and two equivalent Ho(3) atoms. is represented by the CIF file [CIF]
data_Ho3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.444
_cell_length_b   7.532
_cell_length_c   8.111
_cell_angle_alpha   65.206
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   301.943
_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  0.494  0.998  0.006  1.0
  Ho  Ho1  1  0.506  0.498  0.006  1.0
  Ho  Ho2  1  0.971  0.406  0.770  1.0
  Ho  Ho3  1  0.029  0.906  0.770  1.0
  Ho  Ho4  1  0.963  0.085  0.244  1.0
  Ho  Ho5  1  0.037  0.585  0.244  1.0
  Ta  Ta6  1  0.491  0.238  0.506  1.0
  Ta  Ta7  1  0.509  0.738  0.506  1.0
  O  O8  1  0.713  0.247  0.004  1.0
  O  O9  1  0.189  0.149  0.833  1.0
  O  O10  1  0.287  0.747  0.004  1.0
  O  O11  1  0.704  0.954  0.483  1.0
  O  O12  1  0.302  0.637  0.714  1.0
  O  O13  1  0.305  0.857  0.295  1.0
  O  O14  1  0.811  0.649  0.833  1.0
  O  O15  1  0.762  0.558  0.510  1.0
  O  O16  1  0.296  0.454  0.483  1.0
  O  O17  1  0.164  0.354  0.136  1.0
  O  O18  1  0.698  0.137  0.714  1.0
  O  O19  1  0.695  0.357  0.295  1.0
  O  O20  1  0.238  0.058  0.510  1.0
  O  O21  1  0.836  0.854  0.136  1.0
[/CIF]
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The crystal structure described by Ho3TaO7 crystallizes in the monoclinic Pc space group. There are three inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to one O(2), one O(4), one O(5), one O(7), and two equivalent O(1) atoms to form distorted HoO6 octahedra that share corners with two equivalent Ho(1)O6 octahedra and corners with two equivalent Ta(1)O5 tetrahedra. The corner-sharing octahedral tilt angles are 63°. In the second Ho site, Ho(2) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(6), one O(7), two equivalent O(2), and two equivalent O(4) atoms. In the third Ho site, Ho(3) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(6), two equivalent O(5), and two equivalent O(7) atoms. Ta(1) is bonded to one O(4), one O(5), one O(6), and two equivalent O(3) atoms to form distorted TaO5 tetrahedra that share corners with two equivalent Ho(1)O6 octahedra and corners with two equivalent Ta(1)O5 tetrahedra. The corner-sharing octahedral tilt angles range from 61-64°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Ho(2), one Ho(3), and two equivalent Ho(1) atoms to form corner-sharing OHo4 tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ho(1) and two equivalent Ho(2) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ho(2), one Ho(3), and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ho(1), two equivalent Ho(2), and one Ta(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ho(1), two equivalent Ho(3), and one Ta(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Ho(2), one Ho(3), and one Ta(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ho(1), one Ho(2), and two equivalent Ho(3) atoms. is represented by the CIF file [CIF]
data_Ho3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.444
_cell_length_b   7.532
_cell_length_c   8.111
_cell_angle_alpha   65.206
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   301.943
_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  0.494  0.998  0.006  1.0
  Ho  Ho1  1  0.506  0.498  0.006  1.0
  Ho  Ho2  1  0.971  0.406  0.770  1.0
  Ho  Ho3  1  0.029  0.906  0.770  1.0
  Ho  Ho4  1  0.963  0.085  0.244  1.0
  Ho  Ho5  1  0.037  0.585  0.244  1.0
  Ta  Ta6  1  0.491  0.238  0.506  1.0
  Ta  Ta7  1  0.509  0.738  0.506  1.0
  O  O8  1  0.713  0.247  0.004  1.0
  O  O9  1  0.189  0.149  0.833  1.0
  O  O10  1  0.287  0.747  0.004  1.0
  O  O11  1  0.704  0.954  0.483  1.0
  O  O12  1  0.302  0.637  0.714  1.0
  O  O13  1  0.305  0.857  0.295  1.0
  O  O14  1  0.811  0.649  0.833  1.0
  O  O15  1  0.762  0.558  0.510  1.0
  O  O16  1  0.296  0.454  0.483  1.0
  O  O17  1  0.164  0.354  0.136  1.0
  O  O18  1  0.698  0.137  0.714  1.0
  O  O19  1  0.695  0.357  0.295  1.0
  O  O20  1  0.238  0.058  0.510  1.0
  O  O21  1  0.836  0.854  0.136  1.0
[/CIF]
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