The material structure described by MgTbSe3 is Ilmenite structured and crystallizes in the trigonal R-3 space group. Mg(1) is bonded to six equivalent Se(1) atoms to form MgSe6 octahedra that share corners with nine equivalent Tb(1)Se6 octahedra, edges with three equivalent Mg(1)Se6 octahedra, and  a faceface with one Tb(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-56°. Tb(1) is bonded to six equivalent Se(1) atoms to form TbSe6 octahedra that share corners with nine equivalent Mg(1)Se6 octahedra, edges with three equivalent Tb(1)Se6 octahedra, and  a faceface with one Mg(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-56°. Se(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Tb(1) atoms. is represented by the CIF card [CIF]
data_TbMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.930
_cell_length_b   6.930
_cell_length_c   7.574
_cell_angle_alpha   62.774
_cell_angle_beta   62.774
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   267.446
_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  0.161  0.161  0.517  1.0
  Mg  Mg1  1  0.839  0.839  0.483  1.0
  Se  Se2  1  0.223  0.950  0.250  1.0
  Se  Se3  1  0.777  0.050  0.750  1.0
  Se  Se4  1  0.950  0.577  0.250  1.0
  Se  Se5  1  0.050  0.423  0.750  1.0
  Se  Se6  1  0.577  0.223  0.250  1.0
  Se  Se7  1  0.423  0.777  0.750  1.0
  Tb  Tb8  1  0.348  0.348  0.957  1.0
  Tb  Tb9  1  0.652  0.652  0.043  1.0
[/CIF]
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The material structure described by MgTbSe3 is Ilmenite structured and crystallizes in the trigonal R-3 space group. Mg(1) is bonded to six equivalent Se(1) atoms to form MgSe6 octahedra that share corners with nine equivalent Tb(1)Se6 octahedra, edges with three equivalent Mg(1)Se6 octahedra, and  a faceface with one Tb(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-56°. Tb(1) is bonded to six equivalent Se(1) atoms to form TbSe6 octahedra that share corners with nine equivalent Mg(1)Se6 octahedra, edges with three equivalent Tb(1)Se6 octahedra, and  a faceface with one Mg(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-56°. Se(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Tb(1) atoms. is represented by the CIF card [CIF]
data_TbMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.930
_cell_length_b   6.930
_cell_length_c   7.574
_cell_angle_alpha   62.774
_cell_angle_beta   62.774
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   267.446
_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  0.161  0.161  0.517  1.0
  Mg  Mg1  1  0.839  0.839  0.483  1.0
  Se  Se2  1  0.223  0.950  0.250  1.0
  Se  Se3  1  0.777  0.050  0.750  1.0
  Se  Se4  1  0.950  0.577  0.250  1.0
  Se  Se5  1  0.050  0.423  0.750  1.0
  Se  Se6  1  0.577  0.223  0.250  1.0
  Se  Se7  1  0.423  0.777  0.750  1.0
  Tb  Tb8  1  0.348  0.348  0.957  1.0
  Tb  Tb9  1  0.652  0.652  0.043  1.0
[/CIF]
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