The material described by MgTbSe3 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 4-coordinate geometry to two equivalent Se(1) and two equivalent Se(2) atoms. Tb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Mg(1) and two equivalent Tb(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Mg(1) and two equivalent Tb(1) atoms to form edge-sharing SeTb2Mg2 trigonal pyramids. is represented by the CIF card [CIF]
data_TbMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.340
_cell_length_b   7.325
_cell_length_c   7.325
_cell_angle_alpha   70.677
_cell_angle_beta   72.903
_cell_angle_gamma   107.097
_symmetry_Int_Tables_number   1
_cell_volume   276.487
_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
  Mg  Mg0  1  1.000  0.672  0.672  1.0
  Mg  Mg1  1  1.000  0.328  0.328  1.0
  Se  Se2  1  0.766  0.870  0.822  1.0
  Se  Se3  1  0.234  0.130  0.178  1.0
  Se  Se4  1  0.234  0.822  0.870  1.0
  Se  Se5  1  0.766  0.178  0.130  1.0
  Se  Se6  1  0.302  0.596  0.404  1.0
  Se  Se7  1  0.698  0.404  0.596  1.0
  Tb  Tb8  1  0.811  0.774  0.226  1.0
  Tb  Tb9  1  0.189  0.226  0.774  1.0
[/CIF]
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The material described by MgTbSe3 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 4-coordinate geometry to two equivalent Se(1) and two equivalent Se(2) atoms. Tb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Mg(1) and two equivalent Tb(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Mg(1) and two equivalent Tb(1) atoms to form edge-sharing SeTb2Mg2 trigonal pyramids. is represented by the CIF card [CIF]
data_TbMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.340
_cell_length_b   7.325
_cell_length_c   7.325
_cell_angle_alpha   70.677
_cell_angle_beta   72.903
_cell_angle_gamma   107.097
_symmetry_Int_Tables_number   1
_cell_volume   276.487
_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
  Mg  Mg0  1  1.000  0.672  0.672  1.0
  Mg  Mg1  1  1.000  0.328  0.328  1.0
  Se  Se2  1  0.766  0.870  0.822  1.0
  Se  Se3  1  0.234  0.130  0.178  1.0
  Se  Se4  1  0.234  0.822  0.870  1.0
  Se  Se5  1  0.766  0.178  0.130  1.0
  Se  Se6  1  0.302  0.596  0.404  1.0
  Se  Se7  1  0.698  0.404  0.596  1.0
  Tb  Tb8  1  0.811  0.774  0.226  1.0
  Tb  Tb9  1  0.189  0.226  0.774  1.0
[/CIF]
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