The structure described by TbAgSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal I4_1md space group. Tb(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form TbSe6 octahedra that share corners with two equivalent Ag(1)Se6 octahedra, corners with four equivalent Tb(1)Se6 octahedra, edges with four equivalent Tb(1)Se6 octahedra, and edges with eight equivalent Ag(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. Ag(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form AgSe6 octahedra that share corners with two equivalent Tb(1)Se6 octahedra, corners with four equivalent Ag(1)Se6 octahedra, edges with four equivalent Ag(1)Se6 octahedra, and edges with eight equivalent Tb(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Tb(1) and three equivalent Ag(1) atoms to form a mixture of corner and edge-sharing SeTb3Ag3 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the second Se site, Se(2) is bonded to three equivalent Tb(1) and three equivalent Ag(1) atoms to form a mixture of corner and edge-sharing SeTb3Ag3 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. is represented by the CIF card [CIF]
data_TbAgSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.751
_cell_length_b   5.751
_cell_length_c   7.269
_cell_angle_alpha   113.303
_cell_angle_beta   113.303
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   199.253
_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
  Tb  Tb0  1  0.759  0.759  0.518  1.0
  Tb  Tb1  1  0.009  0.509  0.018  1.0
  Ag  Ag2  1  0.264  0.264  0.527  1.0
  Ag  Ag3  1  0.514  0.014  0.027  1.0
  Se  Se4  1  0.999  0.999  0.998  1.0
  Se  Se5  1  0.249  0.749  0.498  1.0
  Se  Se6  1  0.519  0.519  0.037  1.0
  Se  Se7  1  0.769  0.269  0.537  1.0
[/CIF]
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The structure described by TbAgSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal I4_1md space group. Tb(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form TbSe6 octahedra that share corners with two equivalent Ag(1)Se6 octahedra, corners with four equivalent Tb(1)Se6 octahedra, edges with four equivalent Tb(1)Se6 octahedra, and edges with eight equivalent Ag(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. Ag(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form AgSe6 octahedra that share corners with two equivalent Tb(1)Se6 octahedra, corners with four equivalent Ag(1)Se6 octahedra, edges with four equivalent Ag(1)Se6 octahedra, and edges with eight equivalent Tb(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Tb(1) and three equivalent Ag(1) atoms to form a mixture of corner and edge-sharing SeTb3Ag3 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the second Se site, Se(2) is bonded to three equivalent Tb(1) and three equivalent Ag(1) atoms to form a mixture of corner and edge-sharing SeTb3Ag3 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. is represented by the CIF card [CIF]
data_TbAgSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.751
_cell_length_b   5.751
_cell_length_c   7.269
_cell_angle_alpha   113.303
_cell_angle_beta   113.303
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   199.253
_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
  Tb  Tb0  1  0.759  0.759  0.518  1.0
  Tb  Tb1  1  0.009  0.509  0.018  1.0
  Ag  Ag2  1  0.264  0.264  0.527  1.0
  Ag  Ag3  1  0.514  0.014  0.027  1.0
  Se  Se4  1  0.999  0.999  0.998  1.0
  Se  Se5  1  0.249  0.749  0.498  1.0
  Se  Se6  1  0.519  0.519  0.037  1.0
  Se  Se7  1  0.769  0.269  0.537  1.0
[/CIF]
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