The crystal structure described by Dy2Se3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a 8-coordinate geometry to two equivalent Se(2), three equivalent Se(1), and three equivalent Se(3) atoms. In the second Dy site, Dy(2) is bonded to two equivalent Se(1), two equivalent Se(3), and three equivalent Se(2) atoms to form a mixture of distorted corner and edge-sharing DySe7 pentagonal bipyramids. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Dy(2) and three equivalent Dy(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Dy(1) and three equivalent Dy(2) atoms to form a mixture of corner and edge-sharing SeDy5 square pyramids. In the third Se site, Se(3) is bonded to two equivalent Dy(2) and three equivalent Dy(1) atoms to form a mixture of distorted corner and edge-sharing SeDy5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Dy2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.008
_cell_length_b   10.990
_cell_length_c   11.095
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   488.720
_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  0.250  0.998  0.807  1.0
  Dy  Dy1  1  0.750  0.002  0.193  1.0
  Dy  Dy2  1  0.750  0.498  0.693  1.0
  Dy  Dy3  1  0.250  0.502  0.307  1.0
  Dy  Dy4  1  0.250  0.188  0.487  1.0
  Dy  Dy5  1  0.750  0.812  0.513  1.0
  Dy  Dy6  1  0.750  0.688  0.013  1.0
  Dy  Dy7  1  0.250  0.312  0.987  1.0
  Se  Se8  1  0.250  0.305  0.726  1.0
  Se  Se9  1  0.750  0.695  0.274  1.0
  Se  Se10  1  0.750  0.805  0.774  1.0
  Se  Se11  1  0.250  0.195  0.226  1.0
  Se  Se12  1  0.250  0.944  0.382  1.0
  Se  Se13  1  0.750  0.056  0.618  1.0
  Se  Se14  1  0.750  0.444  0.118  1.0
  Se  Se15  1  0.250  0.556  0.882  1.0
  Se  Se16  1  0.250  0.874  0.045  1.0
  Se  Se17  1  0.750  0.126  0.955  1.0
  Se  Se18  1  0.750  0.374  0.455  1.0
  Se  Se19  1  0.250  0.626  0.545  1.0
[/CIF]
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The crystal structure described by Dy2Se3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a 8-coordinate geometry to two equivalent Se(2), three equivalent Se(1), and three equivalent Se(3) atoms. In the second Dy site, Dy(2) is bonded to two equivalent Se(1), two equivalent Se(3), and three equivalent Se(2) atoms to form a mixture of distorted corner and edge-sharing DySe7 pentagonal bipyramids. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Dy(2) and three equivalent Dy(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Dy(1) and three equivalent Dy(2) atoms to form a mixture of corner and edge-sharing SeDy5 square pyramids. In the third Se site, Se(3) is bonded to two equivalent Dy(2) and three equivalent Dy(1) atoms to form a mixture of distorted corner and edge-sharing SeDy5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Dy2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.008
_cell_length_b   10.990
_cell_length_c   11.095
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   488.720
_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  0.250  0.998  0.807  1.0
  Dy  Dy1  1  0.750  0.002  0.193  1.0
  Dy  Dy2  1  0.750  0.498  0.693  1.0
  Dy  Dy3  1  0.250  0.502  0.307  1.0
  Dy  Dy4  1  0.250  0.188  0.487  1.0
  Dy  Dy5  1  0.750  0.812  0.513  1.0
  Dy  Dy6  1  0.750  0.688  0.013  1.0
  Dy  Dy7  1  0.250  0.312  0.987  1.0
  Se  Se8  1  0.250  0.305  0.726  1.0
  Se  Se9  1  0.750  0.695  0.274  1.0
  Se  Se10  1  0.750  0.805  0.774  1.0
  Se  Se11  1  0.250  0.195  0.226  1.0
  Se  Se12  1  0.250  0.944  0.382  1.0
  Se  Se13  1  0.750  0.056  0.618  1.0
  Se  Se14  1  0.750  0.444  0.118  1.0
  Se  Se15  1  0.250  0.556  0.882  1.0
  Se  Se16  1  0.250  0.874  0.045  1.0
  Se  Se17  1  0.750  0.126  0.955  1.0
  Se  Se18  1  0.750  0.374  0.455  1.0
  Se  Se19  1  0.250  0.626  0.545  1.0
[/CIF]
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