The compound described by Ho2Ti2O7 crystallizes in the cubic Fd-3m space group. Ho(1) is bonded to two equivalent O(2) and six equivalent O(1) atoms to form distorted HoO8 hexagonal bipyramids that share edges with six equivalent Ho(1)O8 hexagonal bipyramids and edges with six equivalent Ti(1)O6 octahedra. Ti(1) is bonded to six equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra and edges with six equivalent Ho(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 49°. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ho(1) and two equivalent Ti(1) atoms to form distorted OHo2Ti2 tetrahedra that share corners with two equivalent O(2)Ho4 tetrahedra, corners with twelve equivalent O(1)Ho2Ti2 tetrahedra,  an edgeedge with one O(2)Ho4 tetrahedra, and edges with four equivalent O(1)Ho2Ti2 tetrahedra. In the second O site, O(2) is bonded to four equivalent Ho(1) atoms to form OHo4 tetrahedra that share corners with four equivalent O(2)Ho4 tetrahedra, corners with twelve equivalent O(1)Ho2Ti2 tetrahedra, and edges with six equivalent O(1)Ho2Ti2 tetrahedra. is represented by the CIF file [CIF]
data_Ho2Ti2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.118
_cell_length_b   7.118
_cell_length_c   7.118
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   254.973
_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  0.625  0.125  0.125  1.0
  Ho  Ho1  1  0.125  0.125  0.125  1.0
  Ho  Ho2  1  0.125  0.625  0.125  1.0
  Ho  Ho3  1  0.125  0.125  0.625  1.0
  Ti  Ti4  1  0.625  0.625  0.125  1.0
  Ti  Ti5  1  0.625  0.125  0.625  1.0
  Ti  Ti6  1  0.625  0.625  0.625  1.0
  Ti  Ti7  1  0.125  0.625  0.625  1.0
  O  O8  1  0.956  0.544  0.544  1.0
  O  O9  1  0.706  0.294  0.294  1.0
  O  O10  1  0.706  0.706  0.294  1.0
  O  O11  1  0.956  0.956  0.544  1.0
  O  O12  1  0.956  0.544  0.956  1.0
  O  O13  1  0.706  0.294  0.706  1.0
  O  O14  1  0.294  0.706  0.294  1.0
  O  O15  1  0.000  0.000  0.000  1.0
  O  O16  1  0.294  0.294  0.706  1.0
  O  O17  1  0.294  0.706  0.706  1.0
  O  O18  1  0.250  0.250  0.250  1.0
  O  O19  1  0.544  0.956  0.544  1.0
  O  O20  1  0.544  0.544  0.956  1.0
  O  O21  1  0.544  0.956  0.956  1.0
[/CIF]
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The compound described by Ho2Ti2O7 crystallizes in the cubic Fd-3m space group. Ho(1) is bonded to two equivalent O(2) and six equivalent O(1) atoms to form distorted HoO8 hexagonal bipyramids that share edges with six equivalent Ho(1)O8 hexagonal bipyramids and edges with six equivalent Ti(1)O6 octahedra. Ti(1) is bonded to six equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra and edges with six equivalent Ho(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 49°. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ho(1) and two equivalent Ti(1) atoms to form distorted OHo2Ti2 tetrahedra that share corners with two equivalent O(2)Ho4 tetrahedra, corners with twelve equivalent O(1)Ho2Ti2 tetrahedra,  an edgeedge with one O(2)Ho4 tetrahedra, and edges with four equivalent O(1)Ho2Ti2 tetrahedra. In the second O site, O(2) is bonded to four equivalent Ho(1) atoms to form OHo4 tetrahedra that share corners with four equivalent O(2)Ho4 tetrahedra, corners with twelve equivalent O(1)Ho2Ti2 tetrahedra, and edges with six equivalent O(1)Ho2Ti2 tetrahedra. is represented by the CIF file [CIF]
data_Ho2Ti2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.118
_cell_length_b   7.118
_cell_length_c   7.118
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   254.973
_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  0.625  0.125  0.125  1.0
  Ho  Ho1  1  0.125  0.125  0.125  1.0
  Ho  Ho2  1  0.125  0.625  0.125  1.0
  Ho  Ho3  1  0.125  0.125  0.625  1.0
  Ti  Ti4  1  0.625  0.625  0.125  1.0
  Ti  Ti5  1  0.625  0.125  0.625  1.0
  Ti  Ti6  1  0.625  0.625  0.625  1.0
  Ti  Ti7  1  0.125  0.625  0.625  1.0
  O  O8  1  0.956  0.544  0.544  1.0
  O  O9  1  0.706  0.294  0.294  1.0
  O  O10  1  0.706  0.706  0.294  1.0
  O  O11  1  0.956  0.956  0.544  1.0
  O  O12  1  0.956  0.544  0.956  1.0
  O  O13  1  0.706  0.294  0.706  1.0
  O  O14  1  0.294  0.706  0.294  1.0
  O  O15  1  0.000  0.000  0.000  1.0
  O  O16  1  0.294  0.294  0.706  1.0
  O  O17  1  0.294  0.706  0.706  1.0
  O  O18  1  0.250  0.250  0.250  1.0
  O  O19  1  0.544  0.956  0.544  1.0
  O  O20  1  0.544  0.544  0.956  1.0
  O  O21  1  0.544  0.956  0.956  1.0
[/CIF]
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