The crystal structure described by MgYbSe3 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. Yb(1) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form distorted edge-sharing YbSe4 trigonal pyramids. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to two equivalent Mg(1), one Yb(1), and one Se(1) atom. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Yb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_YbMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.647
_cell_length_b   7.358
_cell_length_c   7.358
_cell_angle_alpha   117.050
_cell_angle_beta   101.401
_cell_angle_gamma   101.401
_symmetry_Int_Tables_number   1
_cell_volume   296.665
_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  0.634  0.366  1.0
  Mg  Mg1  1  1.000  0.366  0.634  1.0
  Se  Se2  1  0.820  0.510  0.927  1.0
  Se  Se3  1  0.180  0.490  0.073  1.0
  Se  Se4  1  0.180  0.073  0.490  1.0
  Se  Se5  1  0.820  0.927  0.510  1.0
  Se  Se6  1  0.278  0.731  0.731  1.0
  Se  Se7  1  0.722  0.269  0.269  1.0
  Yb  Yb8  1  0.722  0.891  0.891  1.0
  Yb  Yb9  1  0.278  0.109  0.109  1.0
[/CIF]
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The crystal structure described by MgYbSe3 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. Yb(1) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form distorted edge-sharing YbSe4 trigonal pyramids. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to two equivalent Mg(1), one Yb(1), and one Se(1) atom. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Yb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_YbMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.647
_cell_length_b   7.358
_cell_length_c   7.358
_cell_angle_alpha   117.050
_cell_angle_beta   101.401
_cell_angle_gamma   101.401
_symmetry_Int_Tables_number   1
_cell_volume   296.665
_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  0.634  0.366  1.0
  Mg  Mg1  1  1.000  0.366  0.634  1.0
  Se  Se2  1  0.820  0.510  0.927  1.0
  Se  Se3  1  0.180  0.490  0.073  1.0
  Se  Se4  1  0.180  0.073  0.490  1.0
  Se  Se5  1  0.820  0.927  0.510  1.0
  Se  Se6  1  0.278  0.731  0.731  1.0
  Se  Se7  1  0.722  0.269  0.269  1.0
  Yb  Yb8  1  0.722  0.891  0.891  1.0
  Yb  Yb9  1  0.278  0.109  0.109  1.0
[/CIF]
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