The structure described by GdAgSe2 crystallizes in the tetragonal I4_1md space group. Gd(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form GdSe6 octahedra that share corners with four equivalent Gd(1)Se6 octahedra, corners with three equivalent Ag(1)Se5 trigonal bipyramids, edges with four equivalent Gd(1)Se6 octahedra, and edges with six equivalent Ag(1)Se5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 6-8°. Ag(1) is bonded to two equivalent Se(1) and three equivalent Se(2) atoms to form AgSe5 trigonal bipyramids that share corners with three equivalent Gd(1)Se6 octahedra, corners with eight equivalent Ag(1)Se5 trigonal bipyramids, and edges with six equivalent Gd(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-79°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Gd(1) and two equivalent Ag(1) atoms to form SeGd3Ag2 trigonal bipyramids that share corners with three equivalent Se(2)Gd3Ag3 octahedra, corners with eight equivalent Se(1)Gd3Ag2 trigonal bipyramids, and edges with six equivalent Se(2)Gd3Ag3 octahedra. The corner-sharing octahedral tilt angles range from 0-79°. In the second Se site, Se(2) is bonded to three equivalent Gd(1) and three equivalent Ag(1) atoms to form SeGd3Ag3 octahedra that share corners with four equivalent Se(2)Gd3Ag3 octahedra, corners with three equivalent Se(1)Gd3Ag2 trigonal bipyramids, edges with four equivalent Se(2)Gd3Ag3 octahedra, and edges with six equivalent Se(1)Gd3Ag2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 6-8°. is represented by the CIF file [CIF]
data_GdAgSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.363
_cell_length_b   7.363
_cell_length_c   7.363
_cell_angle_alpha   134.317
_cell_angle_beta   134.317
_cell_angle_gamma   66.593
_symmetry_Int_Tables_number   1
_cell_volume   201.125
_cell_formula_units_Z   2
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  0.747  0.747  0.000  1.0
  Gd  Gd1  1  0.497  0.997  0.500  1.0
  Ag  Ag2  1  0.217  0.217  0.000  1.0
  Ag  Ag3  1  0.967  0.467  0.500  1.0
  Se  Se4  1  0.513  0.513  0.000  1.0
  Se  Se5  1  0.263  0.763  0.500  1.0
  Se  Se6  1  0.984  0.984  0.000  1.0
  Se  Se7  1  0.734  0.234  0.500  1.0
[/CIF]
.
The structure described by GdAgSe2 crystallizes in the tetragonal I4_1md space group. Gd(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form GdSe6 octahedra that share corners with four equivalent Gd(1)Se6 octahedra, corners with three equivalent Ag(1)Se5 trigonal bipyramids, edges with four equivalent Gd(1)Se6 octahedra, and edges with six equivalent Ag(1)Se5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 6-8°. Ag(1) is bonded to two equivalent Se(1) and three equivalent Se(2) atoms to form AgSe5 trigonal bipyramids that share corners with three equivalent Gd(1)Se6 octahedra, corners with eight equivalent Ag(1)Se5 trigonal bipyramids, and edges with six equivalent Gd(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-79°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Gd(1) and two equivalent Ag(1) atoms to form SeGd3Ag2 trigonal bipyramids that share corners with three equivalent Se(2)Gd3Ag3 octahedra, corners with eight equivalent Se(1)Gd3Ag2 trigonal bipyramids, and edges with six equivalent Se(2)Gd3Ag3 octahedra. The corner-sharing octahedral tilt angles range from 0-79°. In the second Se site, Se(2) is bonded to three equivalent Gd(1) and three equivalent Ag(1) atoms to form SeGd3Ag3 octahedra that share corners with four equivalent Se(2)Gd3Ag3 octahedra, corners with three equivalent Se(1)Gd3Ag2 trigonal bipyramids, edges with four equivalent Se(2)Gd3Ag3 octahedra, and edges with six equivalent Se(1)Gd3Ag2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 6-8°. is represented by the CIF file [CIF]
data_GdAgSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.363
_cell_length_b   7.363
_cell_length_c   7.363
_cell_angle_alpha   134.317
_cell_angle_beta   134.317
_cell_angle_gamma   66.593
_symmetry_Int_Tables_number   1
_cell_volume   201.125
_cell_formula_units_Z   2
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  0.747  0.747  0.000  1.0
  Gd  Gd1  1  0.497  0.997  0.500  1.0
  Ag  Ag2  1  0.217  0.217  0.000  1.0
  Ag  Ag3  1  0.967  0.467  0.500  1.0
  Se  Se4  1  0.513  0.513  0.000  1.0
  Se  Se5  1  0.263  0.763  0.500  1.0
  Se  Se6  1  0.984  0.984  0.000  1.0
  Se  Se7  1  0.734  0.234  0.500  1.0
[/CIF]
.