The material described by Eu(YSe2)2 crystallizes in the orthorhombic Pnma space group. 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 two inequivalent Y sites. In the first Y site, Y(1) 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 YSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-65°. In the second Y site, Y(2) 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 YSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-65°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Eu(1), one Y(2), and two equivalent Y(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Y3 trigonal bipyramids. In the second Se site, Se(2) is bonded to two equivalent Eu(1) and three equivalent Y(2) atoms to form a mixture of edge and corner-sharing SeEu2Y3 square pyramids. In the third Se site, Se(3) is bonded to two equivalent Eu(1), one Y(1), and two equivalent Y(2) atoms to form a mixture of distorted edge and corner-sharing SeEu2Y3 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to two equivalent Eu(1) and three equivalent Y(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Y3 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Eu(YSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.124
_cell_length_b   12.490
_cell_length_c   14.899
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   767.500
_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  0.750  0.742  0.164  1.0
  Eu  Eu1  1  0.750  0.242  0.336  1.0
  Eu  Eu2  1  0.250  0.258  0.836  1.0
  Eu  Eu3  1  0.250  0.758  0.664  1.0
  Y  Y4  1  0.750  0.066  0.111  1.0
  Y  Y5  1  0.750  0.566  0.389  1.0
  Y  Y6  1  0.250  0.934  0.889  1.0
  Y  Y7  1  0.250  0.434  0.611  1.0
  Y  Y8  1  0.750  0.082  0.598  1.0
  Y  Y9  1  0.750  0.582  0.902  1.0
  Y  Y10  1  0.250  0.918  0.402  1.0
  Y  Y11  1  0.250  0.418  0.098  1.0
  Se  Se12  1  0.750  0.293  0.677  1.0
  Se  Se13  1  0.750  0.793  0.823  1.0
  Se  Se14  1  0.250  0.707  0.323  1.0
  Se  Se15  1  0.250  0.207  0.177  1.0
  Se  Se16  1  0.750  0.367  0.970  1.0
  Se  Se17  1  0.750  0.867  0.530  1.0
  Se  Se18  1  0.250  0.633  0.030  1.0
  Se  Se19  1  0.250  0.133  0.470  1.0
  Se  Se20  1  0.750  0.476  0.215  1.0
  Se  Se21  1  0.750  0.976  0.285  1.0
  Se  Se22  1  0.250  0.524  0.785  1.0
  Se  Se23  1  0.250  0.024  0.715  1.0
  Se  Se24  1  0.750  0.090  0.921  1.0
  Se  Se25  1  0.750  0.590  0.579  1.0
  Se  Se26  1  0.250  0.910  0.079  1.0
  Se  Se27  1  0.250  0.410  0.421  1.0
[/CIF]
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The material described by Eu(YSe2)2 crystallizes in the orthorhombic Pnma space group. 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 two inequivalent Y sites. In the first Y site, Y(1) 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 YSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-65°. In the second Y site, Y(2) 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 YSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-65°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Eu(1), one Y(2), and two equivalent Y(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Y3 trigonal bipyramids. In the second Se site, Se(2) is bonded to two equivalent Eu(1) and three equivalent Y(2) atoms to form a mixture of edge and corner-sharing SeEu2Y3 square pyramids. In the third Se site, Se(3) is bonded to two equivalent Eu(1), one Y(1), and two equivalent Y(2) atoms to form a mixture of distorted edge and corner-sharing SeEu2Y3 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to two equivalent Eu(1) and three equivalent Y(1) atoms to form a mixture of distorted edge and corner-sharing SeEu2Y3 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Eu(YSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.124
_cell_length_b   12.490
_cell_length_c   14.899
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   767.500
_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  0.750  0.742  0.164  1.0
  Eu  Eu1  1  0.750  0.242  0.336  1.0
  Eu  Eu2  1  0.250  0.258  0.836  1.0
  Eu  Eu3  1  0.250  0.758  0.664  1.0
  Y  Y4  1  0.750  0.066  0.111  1.0
  Y  Y5  1  0.750  0.566  0.389  1.0
  Y  Y6  1  0.250  0.934  0.889  1.0
  Y  Y7  1  0.250  0.434  0.611  1.0
  Y  Y8  1  0.750  0.082  0.598  1.0
  Y  Y9  1  0.750  0.582  0.902  1.0
  Y  Y10  1  0.250  0.918  0.402  1.0
  Y  Y11  1  0.250  0.418  0.098  1.0
  Se  Se12  1  0.750  0.293  0.677  1.0
  Se  Se13  1  0.750  0.793  0.823  1.0
  Se  Se14  1  0.250  0.707  0.323  1.0
  Se  Se15  1  0.250  0.207  0.177  1.0
  Se  Se16  1  0.750  0.367  0.970  1.0
  Se  Se17  1  0.750  0.867  0.530  1.0
  Se  Se18  1  0.250  0.633  0.030  1.0
  Se  Se19  1  0.250  0.133  0.470  1.0
  Se  Se20  1  0.750  0.476  0.215  1.0
  Se  Se21  1  0.750  0.976  0.285  1.0
  Se  Se22  1  0.250  0.524  0.785  1.0
  Se  Se23  1  0.250  0.024  0.715  1.0
  Se  Se24  1  0.750  0.090  0.921  1.0
  Se  Se25  1  0.750  0.590  0.579  1.0
  Se  Se26  1  0.250  0.910  0.079  1.0
  Se  Se27  1  0.250  0.410  0.421  1.0
[/CIF]
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