The material structure described by EuEr2Se4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to one Se(1), two equivalent Se(3), and three equivalent Se(2) atoms to form a mixture of edge and corner-sharing ErSe6 octahedra. The corner-sharing octahedral tilt angles range from 47-63°. In the second Er site, Er(2) is bonded to one Se(3), two equivalent Se(1), and three equivalent Se(4) atoms to form a mixture of edge and corner-sharing ErSe6 octahedra. The corner-sharing octahedral tilt angles range from 47-63°. Eu(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Er(1), two equivalent Er(2), and two equivalent Eu(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Er3 trigonal bipyramids. In the second Se site, Se(2) is bonded to three equivalent Er(1) and two equivalent Eu(1) atoms to form a mixture of edge and corner-sharing SeEu2Er3 square pyramids. In the third Se site, Se(3) is bonded to one Er(2), two equivalent Er(1), and two equivalent Eu(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Er3 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to three equivalent Er(2) and two equivalent Eu(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Er3 trigonal bipyramids. is represented by the CIF file [CIF]
data_Eu(ErSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.084
_cell_length_b   12.453
_cell_length_c   14.757
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   750.435
_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
  Eu  Eu0  1  0.250  0.759  0.335  1.0
  Eu  Eu1  1  0.250  0.259  0.165  1.0
  Eu  Eu2  1  0.750  0.241  0.665  1.0
  Eu  Eu3  1  0.750  0.741  0.835  1.0
  Er  Er4  1  0.250  0.416  0.903  1.0
  Er  Er5  1  0.250  0.916  0.597  1.0
  Er  Er6  1  0.750  0.584  0.097  1.0
  Er  Er7  1  0.750  0.084  0.403  1.0
  Er  Er8  1  0.250  0.439  0.389  1.0
  Er  Er9  1  0.250  0.939  0.111  1.0
  Er  Er10  1  0.750  0.561  0.611  1.0
  Er  Er11  1  0.750  0.061  0.889  1.0
  Se  Se12  1  0.250  0.204  0.827  1.0
  Se  Se13  1  0.250  0.704  0.673  1.0
  Se  Se14  1  0.750  0.796  0.173  1.0
  Se  Se15  1  0.750  0.296  0.327  1.0
  Se  Se16  1  0.250  0.129  0.532  1.0
  Se  Se17  1  0.250  0.629  0.968  1.0
  Se  Se18  1  0.750  0.871  0.468  1.0
  Se  Se19  1  0.750  0.371  0.032  1.0
  Se  Se20  1  0.250  0.528  0.215  1.0
  Se  Se21  1  0.250  0.028  0.285  1.0
  Se  Se22  1  0.750  0.472  0.785  1.0
  Se  Se23  1  0.750  0.972  0.715  1.0
  Se  Se24  1  0.250  0.408  0.577  1.0
  Se  Se25  1  0.250  0.908  0.923  1.0
  Se  Se26  1  0.750  0.592  0.423  1.0
  Se  Se27  1  0.750  0.092  0.077  1.0
[/CIF]
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The material structure described by EuEr2Se4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to one Se(1), two equivalent Se(3), and three equivalent Se(2) atoms to form a mixture of edge and corner-sharing ErSe6 octahedra. The corner-sharing octahedral tilt angles range from 47-63°. In the second Er site, Er(2) is bonded to one Se(3), two equivalent Se(1), and three equivalent Se(4) atoms to form a mixture of edge and corner-sharing ErSe6 octahedra. The corner-sharing octahedral tilt angles range from 47-63°. Eu(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Er(1), two equivalent Er(2), and two equivalent Eu(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Er3 trigonal bipyramids. In the second Se site, Se(2) is bonded to three equivalent Er(1) and two equivalent Eu(1) atoms to form a mixture of edge and corner-sharing SeEu2Er3 square pyramids. In the third Se site, Se(3) is bonded to one Er(2), two equivalent Er(1), and two equivalent Eu(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Er3 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to three equivalent Er(2) and two equivalent Eu(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Er3 trigonal bipyramids. is represented by the CIF file [CIF]
data_Eu(ErSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.084
_cell_length_b   12.453
_cell_length_c   14.757
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   750.435
_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
  Eu  Eu0  1  0.250  0.759  0.335  1.0
  Eu  Eu1  1  0.250  0.259  0.165  1.0
  Eu  Eu2  1  0.750  0.241  0.665  1.0
  Eu  Eu3  1  0.750  0.741  0.835  1.0
  Er  Er4  1  0.250  0.416  0.903  1.0
  Er  Er5  1  0.250  0.916  0.597  1.0
  Er  Er6  1  0.750  0.584  0.097  1.0
  Er  Er7  1  0.750  0.084  0.403  1.0
  Er  Er8  1  0.250  0.439  0.389  1.0
  Er  Er9  1  0.250  0.939  0.111  1.0
  Er  Er10  1  0.750  0.561  0.611  1.0
  Er  Er11  1  0.750  0.061  0.889  1.0
  Se  Se12  1  0.250  0.204  0.827  1.0
  Se  Se13  1  0.250  0.704  0.673  1.0
  Se  Se14  1  0.750  0.796  0.173  1.0
  Se  Se15  1  0.750  0.296  0.327  1.0
  Se  Se16  1  0.250  0.129  0.532  1.0
  Se  Se17  1  0.250  0.629  0.968  1.0
  Se  Se18  1  0.750  0.871  0.468  1.0
  Se  Se19  1  0.750  0.371  0.032  1.0
  Se  Se20  1  0.250  0.528  0.215  1.0
  Se  Se21  1  0.250  0.028  0.285  1.0
  Se  Se22  1  0.750  0.472  0.785  1.0
  Se  Se23  1  0.750  0.972  0.715  1.0
  Se  Se24  1  0.250  0.408  0.577  1.0
  Se  Se25  1  0.250  0.908  0.923  1.0
  Se  Se26  1  0.750  0.592  0.423  1.0
  Se  Se27  1  0.750  0.092  0.077  1.0
[/CIF]
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