The crystal structure described by Gd2Se3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded to two equivalent Se(1), two equivalent Se(3), and three equivalent Se(2) atoms to form a mixture of distorted edge and corner-sharing GdSe7 pentagonal bipyramids. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to two equivalent Se(2), three equivalent Se(1), and three equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Gd(1) and three equivalent Gd(2) atoms to form a mixture of distorted edge and corner-sharing SeGd5 trigonal bipyramids. In the second Se site, Se(2) is bonded to two equivalent Gd(2) and three equivalent Gd(1) atoms to form a mixture of edge and corner-sharing SeGd5 square pyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent Gd(1) and three equivalent Gd(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Gd2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.071
_cell_length_b   11.062
_cell_length_c   11.225
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   505.507
_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
  Gd  Gd0  1  0.250  0.187  0.489  1.0
  Gd  Gd1  1  0.250  0.313  0.989  1.0
  Gd  Gd2  1  0.750  0.813  0.511  1.0
  Gd  Gd3  1  0.750  0.687  0.011  1.0
  Gd  Gd4  1  0.750  0.496  0.693  1.0
  Gd  Gd5  1  0.750  0.004  0.193  1.0
  Gd  Gd6  1  0.250  0.504  0.307  1.0
  Gd  Gd7  1  0.250  0.996  0.807  1.0
  Se  Se8  1  0.250  0.626  0.546  1.0
  Se  Se9  1  0.250  0.874  0.046  1.0
  Se  Se10  1  0.750  0.374  0.454  1.0
  Se  Se11  1  0.750  0.126  0.954  1.0
  Se  Se12  1  0.750  0.056  0.619  1.0
  Se  Se13  1  0.750  0.444  0.119  1.0
  Se  Se14  1  0.250  0.944  0.381  1.0
  Se  Se15  1  0.250  0.556  0.881  1.0
  Se  Se16  1  0.250  0.303  0.727  1.0
  Se  Se17  1  0.250  0.197  0.227  1.0
  Se  Se18  1  0.750  0.697  0.273  1.0
  Se  Se19  1  0.750  0.803  0.773  1.0
[/CIF]
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The crystal structure described by Gd2Se3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded to two equivalent Se(1), two equivalent Se(3), and three equivalent Se(2) atoms to form a mixture of distorted edge and corner-sharing GdSe7 pentagonal bipyramids. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to two equivalent Se(2), three equivalent Se(1), and three equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Gd(1) and three equivalent Gd(2) atoms to form a mixture of distorted edge and corner-sharing SeGd5 trigonal bipyramids. In the second Se site, Se(2) is bonded to two equivalent Gd(2) and three equivalent Gd(1) atoms to form a mixture of edge and corner-sharing SeGd5 square pyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent Gd(1) and three equivalent Gd(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Gd2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.071
_cell_length_b   11.062
_cell_length_c   11.225
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   505.507
_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
  Gd  Gd0  1  0.250  0.187  0.489  1.0
  Gd  Gd1  1  0.250  0.313  0.989  1.0
  Gd  Gd2  1  0.750  0.813  0.511  1.0
  Gd  Gd3  1  0.750  0.687  0.011  1.0
  Gd  Gd4  1  0.750  0.496  0.693  1.0
  Gd  Gd5  1  0.750  0.004  0.193  1.0
  Gd  Gd6  1  0.250  0.504  0.307  1.0
  Gd  Gd7  1  0.250  0.996  0.807  1.0
  Se  Se8  1  0.250  0.626  0.546  1.0
  Se  Se9  1  0.250  0.874  0.046  1.0
  Se  Se10  1  0.750  0.374  0.454  1.0
  Se  Se11  1  0.750  0.126  0.954  1.0
  Se  Se12  1  0.750  0.056  0.619  1.0
  Se  Se13  1  0.750  0.444  0.119  1.0
  Se  Se14  1  0.250  0.944  0.381  1.0
  Se  Se15  1  0.250  0.556  0.881  1.0
  Se  Se16  1  0.250  0.303  0.727  1.0
  Se  Se17  1  0.250  0.197  0.227  1.0
  Se  Se18  1  0.750  0.697  0.273  1.0
  Se  Se19  1  0.750  0.803  0.773  1.0
[/CIF]
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