The crystal structure described by Gd5AgSe8 crystallizes in the tetragonal I-4 space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. Ag(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Gd(2), four equivalent Gd(1), and one Ag(1) atom to form a mixture of distorted face, edge, and corner-sharing SeGd5Ag octahedra. The corner-sharing octahedral tilt angles range from 17-47°. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Gd(2), four equivalent Gd(1), and one Ag(1) atom. is represented by the CIF file [CIF]
data_Gd5AgSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.613
_cell_length_b   7.613
_cell_length_c   7.613
_cell_angle_alpha   109.769
_cell_angle_beta   109.769
_cell_angle_gamma   108.877
_symmetry_Int_Tables_number   1
_cell_volume   339.676
_cell_formula_units_Z   1
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  0.114  0.748  0.871  1.0
  Gd  Gd1  1  0.252  0.624  0.366  1.0
  Gd  Gd2  1  0.376  0.242  0.629  1.0
  Gd  Gd3  1  0.625  0.375  0.250  1.0
  Gd  Gd4  1  0.758  0.886  0.134  1.0
  Ag  Ag5  1  0.875  0.125  0.750  1.0
  Se  Se6  1  0.994  0.855  0.501  1.0
  Se  Se7  1  0.145  0.146  0.139  1.0
  Se  Se8  1  0.507  0.006  0.361  1.0
  Se  Se9  1  0.373  0.515  0.008  1.0
  Se  Se10  1  0.635  0.627  0.642  1.0
  Se  Se11  1  0.485  0.993  0.858  1.0
  Se  Se12  1  0.854  0.493  0.999  1.0
  Se  Se13  1  0.007  0.365  0.492  1.0
[/CIF]
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The crystal structure described by Gd5AgSe8 crystallizes in the tetragonal I-4 space group. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. Ag(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Gd(2), four equivalent Gd(1), and one Ag(1) atom to form a mixture of distorted face, edge, and corner-sharing SeGd5Ag octahedra. The corner-sharing octahedral tilt angles range from 17-47°. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Gd(2), four equivalent Gd(1), and one Ag(1) atom. is represented by the CIF file [CIF]
data_Gd5AgSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.613
_cell_length_b   7.613
_cell_length_c   7.613
_cell_angle_alpha   109.769
_cell_angle_beta   109.769
_cell_angle_gamma   108.877
_symmetry_Int_Tables_number   1
_cell_volume   339.676
_cell_formula_units_Z   1
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  0.114  0.748  0.871  1.0
  Gd  Gd1  1  0.252  0.624  0.366  1.0
  Gd  Gd2  1  0.376  0.242  0.629  1.0
  Gd  Gd3  1  0.625  0.375  0.250  1.0
  Gd  Gd4  1  0.758  0.886  0.134  1.0
  Ag  Ag5  1  0.875  0.125  0.750  1.0
  Se  Se6  1  0.994  0.855  0.501  1.0
  Se  Se7  1  0.145  0.146  0.139  1.0
  Se  Se8  1  0.507  0.006  0.361  1.0
  Se  Se9  1  0.373  0.515  0.008  1.0
  Se  Se10  1  0.635  0.627  0.642  1.0
  Se  Se11  1  0.485  0.993  0.858  1.0
  Se  Se12  1  0.854  0.493  0.999  1.0
  Se  Se13  1  0.007  0.365  0.492  1.0
[/CIF]
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