The crystal structure described by Dy2Ti2O7 crystallizes in the monoclinic P2_1 space group. There are four inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(4), one O(9), two equivalent O(13), and two equivalent O(6) atoms. In the second Dy site, Dy(2) is bonded in a 7-coordinate geometry to one O(12), one O(3), one O(8), two equivalent O(2), and two equivalent O(5) atoms. In the third Dy site, Dy(3) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(13), one O(14), one O(6), one O(7), and one O(9) atom. In the fourth Dy site, Dy(4) is bonded in a 8-coordinate geometry to one O(10), one O(14), one O(2), one O(5), one O(7), one O(8), and two equivalent O(12) atoms. There are four inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(5), and one O(7) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 31-45°. In the second Ti site, Ti(2) is bonded to one O(1), one O(11), one O(4), one O(7), and two equivalent O(6) atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 27-45°. In the third Ti site, Ti(3) is bonded to one O(10), one O(12), one O(14), one O(3), one O(8), and one O(9) atom to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 31-50°. In the fourth Ti site, Ti(4) is bonded to one O(11), one O(14), one O(4), one O(9), and two equivalent O(13) atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 27-50°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded to one Dy(1), one Dy(3), one Ti(1), and one Ti(2) atom to form distorted ODy2Ti2 tetrahedra that share  a cornercorner with one O(11)Dy2Ti2 tetrahedra,  a cornercorner with one O(2)Dy3Ti tetrahedra,  a cornercorner with one O(5)Dy3Ti tetrahedra, corners with two equivalent O(9)Dy2Ti2 tetrahedra, and  an edgeedge with one O(11)Dy2Ti2 tetrahedra. In the second O site, O(2) is bonded to one Dy(4), two equivalent Dy(2), and one Ti(1) atom to form distorted ODy3Ti tetrahedra that share  a cornercorner with one O(1)Dy2Ti2 tetrahedra, corners with two equivalent O(12)Dy3Ti tetrahedra, corners with two equivalent O(2)Dy3Ti tetrahedra,  an edgeedge with one O(12)Dy3Ti tetrahedra, and edges with three equivalent O(5)Dy3Ti tetrahedra. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Dy(2), one Ti(1), and one Ti(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Dy(1), one Ti(2), and one Ti(4) atom. In the fifth O site, O(5) is bonded to one Dy(4), two equivalent Dy(2), and one Ti(1) atom to form distorted ODy3Ti tetrahedra that share  a cornercorner with one O(1)Dy2Ti2 tetrahedra, corners with two equivalent O(5)Dy3Ti tetrahedra, corners with four equivalent O(12)Dy3Ti tetrahedra, and edges with three equivalent O(2)Dy3Ti tetrahedra. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Dy(3), two equivalent Dy(1), and two equivalent Ti(2) atoms. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Dy(3), one Dy(4), one Ti(1), and one Ti(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Dy(2), one Dy(4), and one Ti(3) atom. In the ninth O site, O(9) is bonded to one Dy(1), one Dy(3), one Ti(3), and one Ti(4) atom to form distorted ODy2Ti2 tetrahedra that share  a cornercorner with one O(11)Dy2Ti2 tetrahedra,  a cornercorner with one O(12)Dy3Ti tetrahedra, corners with two equivalent O(1)Dy2Ti2 tetrahedra, and  an edgeedge with one O(11)Dy2Ti2 tetrahedra. In the tenth O site, O(10) is bonded in a distorted see-saw-like geometry to one Dy(3), one Dy(4), one Ti(1), and one Ti(3) atom. In the eleventh O site, O(11) is bonded to one Dy(1), one Dy(3), one Ti(2), and one Ti(4) atom to form a mixture of distorted edge and corner-sharing ODy2Ti2 tetrahedra. In the twelfth O site, O(12) is bonded to one Dy(2), two equivalent Dy(4), and one Ti(3) atom to form distorted ODy3Ti tetrahedra that share  a cornercorner with one O(9)Dy2Ti2 tetrahedra, corners with two equivalent O(12)Dy3Ti tetrahedra, corners with two equivalent O(2)Dy3Ti tetrahedra, corners with four equivalent O(5)Dy3Ti tetrahedra, and  an edgeedge with one O(2)Dy3Ti tetrahedra. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Dy(3), two equivalent Dy(1), and two equivalent Ti(4) atoms. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Dy(3), one Dy(4), one Ti(3), and one Ti(4) atom. is represented by the CIF card [CIF]
data_Dy2Ti2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.308
_cell_length_b   7.479
_cell_length_c   13.064
_cell_angle_alpha   81.636
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   513.113
_cell_formula_units_Z   4
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
  Dy  Dy0  1  0.771  0.766  0.923  1.0
  Dy  Dy1  1  0.358  0.858  0.563  1.0
  Dy  Dy2  1  0.247  0.715  0.132  1.0
  Dy  Dy3  1  0.781  0.646  0.386  1.0
  Dy  Dy4  1  0.281  0.354  0.614  1.0
  Dy  Dy5  1  0.747  0.285  0.868  1.0
  Dy  Dy6  1  0.858  0.142  0.437  1.0
  Dy  Dy7  1  0.271  0.234  0.077  1.0
  Ti  Ti8  1  0.283  0.929  0.320  1.0
  Ti  Ti9  1  0.767  0.970  0.121  1.0
  Ti  Ti10  1  0.794  0.590  0.673  1.0
  Ti  Ti11  1  0.267  0.531  0.874  1.0
  Ti  Ti12  1  0.767  0.469  0.126  1.0
  Ti  Ti13  1  0.294  0.410  0.327  1.0
  Ti  Ti14  1  0.267  0.030  0.879  1.0
  Ti  Ti15  1  0.783  0.071  0.680  1.0
  O  O16  1  0.435  0.991  0.179  1.0
  O  O17  1  0.563  0.926  0.408  1.0
  O  O18  1  0.673  0.828  0.686  1.0
  O  O19  1  0.349  0.779  0.884  1.0
  O  O20  1  0.067  0.860  0.431  1.0
  O  O21  1  0.041  0.942  0.024  1.0
  O  O22  1  0.955  0.872  0.232  1.0
  O  O23  1  0.097  0.634  0.617  1.0
  O  O24  1  0.932  0.577  0.822  1.0
  O  O25  1  0.379  0.674  0.305  1.0
  O  O26  1  0.654  0.727  0.091  1.0
  O  O27  1  0.590  0.587  0.553  1.0
  O  O28  1  0.539  0.455  0.974  1.0
  O  O29  1  0.456  0.487  0.764  1.0
  O  O30  1  0.956  0.513  0.236  1.0
  O  O31  1  0.039  0.545  0.026  1.0
  O  O32  1  0.090  0.413  0.447  1.0
  O  O33  1  0.154  0.273  0.909  1.0
  O  O34  1  0.879  0.326  0.695  1.0
  O  O35  1  0.432  0.423  0.178  1.0
  O  O36  1  0.597  0.366  0.383  1.0
  O  O37  1  0.455  0.128  0.768  1.0
  O  O38  1  0.541  0.058  0.976  1.0
  O  O39  1  0.567  0.140  0.569  1.0
  O  O40  1  0.849  0.221  0.116  1.0
  O  O41  1  0.173  0.172  0.314  1.0
  O  O42  1  0.063  0.074  0.592  1.0
  O  O43  1  0.935  0.009  0.821  1.0
[/CIF]
.
The crystal structure described by Dy2Ti2O7 crystallizes in the monoclinic P2_1 space group. There are four inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(4), one O(9), two equivalent O(13), and two equivalent O(6) atoms. In the second Dy site, Dy(2) is bonded in a 7-coordinate geometry to one O(12), one O(3), one O(8), two equivalent O(2), and two equivalent O(5) atoms. In the third Dy site, Dy(3) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(13), one O(14), one O(6), one O(7), and one O(9) atom. In the fourth Dy site, Dy(4) is bonded in a 8-coordinate geometry to one O(10), one O(14), one O(2), one O(5), one O(7), one O(8), and two equivalent O(12) atoms. There are four inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(5), and one O(7) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 31-45°. In the second Ti site, Ti(2) is bonded to one O(1), one O(11), one O(4), one O(7), and two equivalent O(6) atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 27-45°. In the third Ti site, Ti(3) is bonded to one O(10), one O(12), one O(14), one O(3), one O(8), and one O(9) atom to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 31-50°. In the fourth Ti site, Ti(4) is bonded to one O(11), one O(14), one O(4), one O(9), and two equivalent O(13) atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 27-50°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded to one Dy(1), one Dy(3), one Ti(1), and one Ti(2) atom to form distorted ODy2Ti2 tetrahedra that share  a cornercorner with one O(11)Dy2Ti2 tetrahedra,  a cornercorner with one O(2)Dy3Ti tetrahedra,  a cornercorner with one O(5)Dy3Ti tetrahedra, corners with two equivalent O(9)Dy2Ti2 tetrahedra, and  an edgeedge with one O(11)Dy2Ti2 tetrahedra. In the second O site, O(2) is bonded to one Dy(4), two equivalent Dy(2), and one Ti(1) atom to form distorted ODy3Ti tetrahedra that share  a cornercorner with one O(1)Dy2Ti2 tetrahedra, corners with two equivalent O(12)Dy3Ti tetrahedra, corners with two equivalent O(2)Dy3Ti tetrahedra,  an edgeedge with one O(12)Dy3Ti tetrahedra, and edges with three equivalent O(5)Dy3Ti tetrahedra. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Dy(2), one Ti(1), and one Ti(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Dy(1), one Ti(2), and one Ti(4) atom. In the fifth O site, O(5) is bonded to one Dy(4), two equivalent Dy(2), and one Ti(1) atom to form distorted ODy3Ti tetrahedra that share  a cornercorner with one O(1)Dy2Ti2 tetrahedra, corners with two equivalent O(5)Dy3Ti tetrahedra, corners with four equivalent O(12)Dy3Ti tetrahedra, and edges with three equivalent O(2)Dy3Ti tetrahedra. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Dy(3), two equivalent Dy(1), and two equivalent Ti(2) atoms. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Dy(3), one Dy(4), one Ti(1), and one Ti(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Dy(2), one Dy(4), and one Ti(3) atom. In the ninth O site, O(9) is bonded to one Dy(1), one Dy(3), one Ti(3), and one Ti(4) atom to form distorted ODy2Ti2 tetrahedra that share  a cornercorner with one O(11)Dy2Ti2 tetrahedra,  a cornercorner with one O(12)Dy3Ti tetrahedra, corners with two equivalent O(1)Dy2Ti2 tetrahedra, and  an edgeedge with one O(11)Dy2Ti2 tetrahedra. In the tenth O site, O(10) is bonded in a distorted see-saw-like geometry to one Dy(3), one Dy(4), one Ti(1), and one Ti(3) atom. In the eleventh O site, O(11) is bonded to one Dy(1), one Dy(3), one Ti(2), and one Ti(4) atom to form a mixture of distorted edge and corner-sharing ODy2Ti2 tetrahedra. In the twelfth O site, O(12) is bonded to one Dy(2), two equivalent Dy(4), and one Ti(3) atom to form distorted ODy3Ti tetrahedra that share  a cornercorner with one O(9)Dy2Ti2 tetrahedra, corners with two equivalent O(12)Dy3Ti tetrahedra, corners with two equivalent O(2)Dy3Ti tetrahedra, corners with four equivalent O(5)Dy3Ti tetrahedra, and  an edgeedge with one O(2)Dy3Ti tetrahedra. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Dy(3), two equivalent Dy(1), and two equivalent Ti(4) atoms. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Dy(3), one Dy(4), one Ti(3), and one Ti(4) atom. is represented by the CIF card [CIF]
data_Dy2Ti2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.308
_cell_length_b   7.479
_cell_length_c   13.064
_cell_angle_alpha   81.636
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   513.113
_cell_formula_units_Z   4
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
  Dy  Dy0  1  0.771  0.766  0.923  1.0
  Dy  Dy1  1  0.358  0.858  0.563  1.0
  Dy  Dy2  1  0.247  0.715  0.132  1.0
  Dy  Dy3  1  0.781  0.646  0.386  1.0
  Dy  Dy4  1  0.281  0.354  0.614  1.0
  Dy  Dy5  1  0.747  0.285  0.868  1.0
  Dy  Dy6  1  0.858  0.142  0.437  1.0
  Dy  Dy7  1  0.271  0.234  0.077  1.0
  Ti  Ti8  1  0.283  0.929  0.320  1.0
  Ti  Ti9  1  0.767  0.970  0.121  1.0
  Ti  Ti10  1  0.794  0.590  0.673  1.0
  Ti  Ti11  1  0.267  0.531  0.874  1.0
  Ti  Ti12  1  0.767  0.469  0.126  1.0
  Ti  Ti13  1  0.294  0.410  0.327  1.0
  Ti  Ti14  1  0.267  0.030  0.879  1.0
  Ti  Ti15  1  0.783  0.071  0.680  1.0
  O  O16  1  0.435  0.991  0.179  1.0
  O  O17  1  0.563  0.926  0.408  1.0
  O  O18  1  0.673  0.828  0.686  1.0
  O  O19  1  0.349  0.779  0.884  1.0
  O  O20  1  0.067  0.860  0.431  1.0
  O  O21  1  0.041  0.942  0.024  1.0
  O  O22  1  0.955  0.872  0.232  1.0
  O  O23  1  0.097  0.634  0.617  1.0
  O  O24  1  0.932  0.577  0.822  1.0
  O  O25  1  0.379  0.674  0.305  1.0
  O  O26  1  0.654  0.727  0.091  1.0
  O  O27  1  0.590  0.587  0.553  1.0
  O  O28  1  0.539  0.455  0.974  1.0
  O  O29  1  0.456  0.487  0.764  1.0
  O  O30  1  0.956  0.513  0.236  1.0
  O  O31  1  0.039  0.545  0.026  1.0
  O  O32  1  0.090  0.413  0.447  1.0
  O  O33  1  0.154  0.273  0.909  1.0
  O  O34  1  0.879  0.326  0.695  1.0
  O  O35  1  0.432  0.423  0.178  1.0
  O  O36  1  0.597  0.366  0.383  1.0
  O  O37  1  0.455  0.128  0.768  1.0
  O  O38  1  0.541  0.058  0.976  1.0
  O  O39  1  0.567  0.140  0.569  1.0
  O  O40  1  0.849  0.221  0.116  1.0
  O  O41  1  0.173  0.172  0.314  1.0
  O  O42  1  0.063  0.074  0.592  1.0
  O  O43  1  0.935  0.009  0.821  1.0
[/CIF]
.