The material described by Sm2Se2O crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 7-coordinate geometry to two equivalent Se(2), four equivalent Se(1), and one O(1) atom. In the second Sm site, Sm(2) is bonded in a 3-coordinate geometry to one Se(1), three equivalent Se(2), and three equivalent O(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Sm(2) and four equivalent Sm(1) atoms to form distorted SeSm5 trigonal bipyramids that share corners with three equivalent O(1)Sm4 tetrahedra, corners with four equivalent Se(1)Sm5 trigonal bipyramids, edges with two equivalent O(1)Sm4 tetrahedra, and edges with four equivalent Se(1)Sm5 trigonal bipyramids. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Sm(1) and three equivalent Sm(2) atoms. O(1) is bonded to one Sm(1) and three equivalent Sm(2) atoms to form OSm4 tetrahedra that share corners with four equivalent O(1)Sm4 tetrahedra, corners with three equivalent Se(1)Sm5 trigonal bipyramids,  an edgeedge with one O(1)Sm4 tetrahedra, and edges with two equivalent Se(1)Sm5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Sm2Se2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.221
_cell_length_b   7.241
_cell_length_c   8.750
_cell_angle_alpha   79.953
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   450.510
_cell_formula_units_Z   4
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  0.449  0.247  0.144  1.0
  Sm  Sm1  1  0.051  0.747  0.144  1.0
  Sm  Sm2  1  0.851  0.329  0.427  1.0
  Sm  Sm3  1  0.649  0.829  0.427  1.0
  Sm  Sm4  1  0.351  0.171  0.573  1.0
  Sm  Sm5  1  0.149  0.671  0.573  1.0
  Sm  Sm6  1  0.949  0.253  0.856  1.0
  Sm  Sm7  1  0.551  0.753  0.856  1.0
  Se  Se8  1  0.779  0.470  0.077  1.0
  Se  Se9  1  0.721  0.970  0.077  1.0
  Se  Se10  1  0.127  0.072  0.319  1.0
  Se  Se11  1  0.373  0.572  0.319  1.0
  Se  Se12  1  0.627  0.428  0.681  1.0
  Se  Se13  1  0.873  0.928  0.681  1.0
  Se  Se14  1  0.279  0.030  0.923  1.0
  Se  Se15  1  0.221  0.530  0.923  1.0
  O  O16  1  0.585  0.149  0.386  1.0
  O  O17  1  0.915  0.649  0.386  1.0
  O  O18  1  0.085  0.351  0.614  1.0
  O  O19  1  0.415  0.851  0.614  1.0
[/CIF]
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The material described by Sm2Se2O crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 7-coordinate geometry to two equivalent Se(2), four equivalent Se(1), and one O(1) atom. In the second Sm site, Sm(2) is bonded in a 3-coordinate geometry to one Se(1), three equivalent Se(2), and three equivalent O(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Sm(2) and four equivalent Sm(1) atoms to form distorted SeSm5 trigonal bipyramids that share corners with three equivalent O(1)Sm4 tetrahedra, corners with four equivalent Se(1)Sm5 trigonal bipyramids, edges with two equivalent O(1)Sm4 tetrahedra, and edges with four equivalent Se(1)Sm5 trigonal bipyramids. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Sm(1) and three equivalent Sm(2) atoms. O(1) is bonded to one Sm(1) and three equivalent Sm(2) atoms to form OSm4 tetrahedra that share corners with four equivalent O(1)Sm4 tetrahedra, corners with three equivalent Se(1)Sm5 trigonal bipyramids,  an edgeedge with one O(1)Sm4 tetrahedra, and edges with two equivalent Se(1)Sm5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Sm2Se2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.221
_cell_length_b   7.241
_cell_length_c   8.750
_cell_angle_alpha   79.953
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   450.510
_cell_formula_units_Z   4
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  0.449  0.247  0.144  1.0
  Sm  Sm1  1  0.051  0.747  0.144  1.0
  Sm  Sm2  1  0.851  0.329  0.427  1.0
  Sm  Sm3  1  0.649  0.829  0.427  1.0
  Sm  Sm4  1  0.351  0.171  0.573  1.0
  Sm  Sm5  1  0.149  0.671  0.573  1.0
  Sm  Sm6  1  0.949  0.253  0.856  1.0
  Sm  Sm7  1  0.551  0.753  0.856  1.0
  Se  Se8  1  0.779  0.470  0.077  1.0
  Se  Se9  1  0.721  0.970  0.077  1.0
  Se  Se10  1  0.127  0.072  0.319  1.0
  Se  Se11  1  0.373  0.572  0.319  1.0
  Se  Se12  1  0.627  0.428  0.681  1.0
  Se  Se13  1  0.873  0.928  0.681  1.0
  Se  Se14  1  0.279  0.030  0.923  1.0
  Se  Se15  1  0.221  0.530  0.923  1.0
  O  O16  1  0.585  0.149  0.386  1.0
  O  O17  1  0.915  0.649  0.386  1.0
  O  O18  1  0.085  0.351  0.614  1.0
  O  O19  1  0.415  0.851  0.614  1.0
[/CIF]
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