The material structure described by MgSmSe3 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 Sm(1)Se6 octahedra, edges with three equivalent Mg(1)Se6 octahedra, and  a faceface with one Sm(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-57°. Sm(1) is bonded to six equivalent Se(1) atoms to form SmSe6 octahedra that share corners with nine equivalent Mg(1)Se6 octahedra, edges with three equivalent Sm(1)Se6 octahedra, and  a faceface with one Mg(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-57°. Se(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Sm(1) atoms. is represented by the CIF card [CIF]
data_SmMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.991
_cell_length_b   6.991
_cell_length_c   7.645
_cell_angle_alpha   62.789
_cell_angle_beta   62.789
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   274.821
_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  0.516  1.0
  Mg  Mg1  1  0.839  0.839  0.484  1.0
  Se  Se2  1  0.218  0.953  0.252  1.0
  Se  Se3  1  0.782  0.047  0.748  1.0
  Se  Se4  1  0.953  0.577  0.252  1.0
  Se  Se5  1  0.047  0.423  0.748  1.0
  Se  Se6  1  0.577  0.218  0.252  1.0
  Se  Se7  1  0.423  0.782  0.748  1.0
  Sm  Sm8  1  0.349  0.349  0.953  1.0
  Sm  Sm9  1  0.651  0.651  0.047  1.0
[/CIF]
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The material structure described by MgSmSe3 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 Sm(1)Se6 octahedra, edges with three equivalent Mg(1)Se6 octahedra, and  a faceface with one Sm(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-57°. Sm(1) is bonded to six equivalent Se(1) atoms to form SmSe6 octahedra that share corners with nine equivalent Mg(1)Se6 octahedra, edges with three equivalent Sm(1)Se6 octahedra, and  a faceface with one Mg(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-57°. Se(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Sm(1) atoms. is represented by the CIF card [CIF]
data_SmMgSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.991
_cell_length_b   6.991
_cell_length_c   7.645
_cell_angle_alpha   62.789
_cell_angle_beta   62.789
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   274.821
_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  0.516  1.0
  Mg  Mg1  1  0.839  0.839  0.484  1.0
  Se  Se2  1  0.218  0.953  0.252  1.0
  Se  Se3  1  0.782  0.047  0.748  1.0
  Se  Se4  1  0.953  0.577  0.252  1.0
  Se  Se5  1  0.047  0.423  0.748  1.0
  Se  Se6  1  0.577  0.218  0.252  1.0
  Se  Se7  1  0.423  0.782  0.748  1.0
  Sm  Sm8  1  0.349  0.349  0.953  1.0
  Sm  Sm9  1  0.651  0.651  0.047  1.0
[/CIF]
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