The compound described by MgSmS3 is Ilmenite-like structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form distorted MgS6 octahedra that share corners with four equivalent Sm(1)S6 pentagonal pyramids, edges with three equivalent Mg(1)S6 octahedra, and edges with four equivalent Sm(1)S6 pentagonal pyramids. Sm(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form distorted SmS6 pentagonal pyramids that share corners with four equivalent Mg(1)S6 octahedra, edges with four equivalent Mg(1)S6 octahedra,  an edgeedge with one Sm(1)S6 pentagonal pyramid, and  a faceface with one Sm(1)S6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 39-48°. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Sm(1) atoms. In the second S site, S(2) is bonded to two equivalent Mg(1) and two equivalent Sm(1) atoms to form edge-sharing SSm2Mg2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_SmMgS3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.966
_cell_length_b   6.966
_cell_length_c   6.823
_cell_angle_alpha   74.232
_cell_angle_beta   74.232
_cell_angle_gamma   110.982
_symmetry_Int_Tables_number   1
_cell_volume   271.270
_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
  Sm  Sm0  1  0.784  0.784  0.257  1.0
  Sm  Sm1  1  0.216  0.216  0.743  1.0
  Mg  Mg2  1  0.340  0.660  0.000  1.0
  Mg  Mg3  1  0.660  0.340  0.000  1.0
  S  S4  1  0.234  0.927  0.146  1.0
  S  S5  1  0.766  0.073  0.854  1.0
  S  S6  1  0.073  0.766  0.854  1.0
  S  S7  1  0.927  0.234  0.146  1.0
  S  S8  1  0.576  0.576  0.716  1.0
  S  S9  1  0.424  0.424  0.284  1.0
[/CIF]
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The compound described by MgSmS3 is Ilmenite-like structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form distorted MgS6 octahedra that share corners with four equivalent Sm(1)S6 pentagonal pyramids, edges with three equivalent Mg(1)S6 octahedra, and edges with four equivalent Sm(1)S6 pentagonal pyramids. Sm(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form distorted SmS6 pentagonal pyramids that share corners with four equivalent Mg(1)S6 octahedra, edges with four equivalent Mg(1)S6 octahedra,  an edgeedge with one Sm(1)S6 pentagonal pyramid, and  a faceface with one Sm(1)S6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 39-48°. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Sm(1) atoms. In the second S site, S(2) is bonded to two equivalent Mg(1) and two equivalent Sm(1) atoms to form edge-sharing SSm2Mg2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_SmMgS3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.966
_cell_length_b   6.966
_cell_length_c   6.823
_cell_angle_alpha   74.232
_cell_angle_beta   74.232
_cell_angle_gamma   110.982
_symmetry_Int_Tables_number   1
_cell_volume   271.270
_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
  Sm  Sm0  1  0.784  0.784  0.257  1.0
  Sm  Sm1  1  0.216  0.216  0.743  1.0
  Mg  Mg2  1  0.340  0.660  0.000  1.0
  Mg  Mg3  1  0.660  0.340  0.000  1.0
  S  S4  1  0.234  0.927  0.146  1.0
  S  S5  1  0.766  0.073  0.854  1.0
  S  S6  1  0.073  0.766  0.854  1.0
  S  S7  1  0.927  0.234  0.146  1.0
  S  S8  1  0.576  0.576  0.716  1.0
  S  S9  1  0.424  0.424  0.284  1.0
[/CIF]
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