The crystal structure described by MgSmSe3 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. Sm(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 Sm(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Mg(1) and two equivalent Sm(1) atoms to form distorted edge-sharing SeSm2Mg2 trigonal pyramids. is represented by the CIF file [CIF]
data_SmMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.268
_cell_length_b   7.353
_cell_length_c   7.353
_cell_angle_alpha   108.518
_cell_angle_beta   106.604
_cell_angle_gamma   106.604
_symmetry_Int_Tables_number   1
_cell_volume   280.291
_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  0.328  0.672  1.0
  Mg  Mg1  1  1.000  0.672  0.328  1.0
  Se  Se2  1  0.241  0.137  0.824  1.0
  Se  Se3  1  0.759  0.863  0.176  1.0
  Se  Se4  1  0.759  0.176  0.863  1.0
  Se  Se5  1  0.241  0.824  0.137  1.0
  Se  Se6  1  0.698  0.398  0.398  1.0
  Se  Se7  1  0.302  0.602  0.602  1.0
  Sm  Sm8  1  0.178  0.227  0.227  1.0
  Sm  Sm9  1  0.822  0.773  0.773  1.0
[/CIF]
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The crystal structure described by MgSmSe3 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. Sm(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 Sm(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Mg(1) and two equivalent Sm(1) atoms to form distorted edge-sharing SeSm2Mg2 trigonal pyramids. is represented by the CIF file [CIF]
data_SmMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.268
_cell_length_b   7.353
_cell_length_c   7.353
_cell_angle_alpha   108.518
_cell_angle_beta   106.604
_cell_angle_gamma   106.604
_symmetry_Int_Tables_number   1
_cell_volume   280.291
_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  0.328  0.672  1.0
  Mg  Mg1  1  1.000  0.672  0.328  1.0
  Se  Se2  1  0.241  0.137  0.824  1.0
  Se  Se3  1  0.759  0.863  0.176  1.0
  Se  Se4  1  0.759  0.176  0.863  1.0
  Se  Se5  1  0.241  0.824  0.137  1.0
  Se  Se6  1  0.698  0.398  0.398  1.0
  Se  Se7  1  0.302  0.602  0.602  1.0
  Sm  Sm8  1  0.178  0.227  0.227  1.0
  Sm  Sm9  1  0.822  0.773  0.773  1.0
[/CIF]
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