The compound described by Sm2Se2O crystallizes in the orthorhombic Pnma space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 3-coordinate geometry to two equivalent Se(2), three equivalent Se(1), and three equivalent O(1) atoms. In the second Sm site, Sm(2) is bonded to two equivalent Se(1), three equivalent Se(2), and one O(1) atom to form a mixture of distorted edge and corner-sharing SmSe5O octahedra. The corner-sharing octahedral tilt angles are 64°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Sm(2) and three equivalent Sm(1) atoms to form distorted SeSm5 trigonal bipyramids that share corners with five equivalent O(1)Sm4 tetrahedra, edges with three 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(2) and three equivalent Sm(1) atoms to form OSm4 tetrahedra that share corners with two equivalent O(1)Sm4 tetrahedra, corners with five equivalent Se(1)Sm5 trigonal bipyramids, edges with two equivalent O(1)Sm4 tetrahedra, and edges with three equivalent Se(1)Sm5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm2Se2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.010
_cell_length_b   7.145
_cell_length_c   16.347
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   468.435
_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  0.250  0.698  0.038  1.0
  Sm  Sm1  1  0.250  0.259  0.162  1.0
  Sm  Sm2  1  0.750  0.759  0.338  1.0
  Sm  Sm3  1  0.750  0.198  0.462  1.0
  Sm  Sm4  1  0.250  0.802  0.538  1.0
  Sm  Sm5  1  0.250  0.241  0.662  1.0
  Sm  Sm6  1  0.750  0.741  0.838  1.0
  Sm  Sm7  1  0.750  0.302  0.962  1.0
  Se  Se8  1  0.750  0.011  0.099  1.0
  Se  Se9  1  0.750  0.551  0.179  1.0
  Se  Se10  1  0.250  0.051  0.321  1.0
  Se  Se11  1  0.250  0.511  0.401  1.0
  Se  Se12  1  0.750  0.489  0.599  1.0
  Se  Se13  1  0.750  0.949  0.679  1.0
  Se  Se14  1  0.250  0.449  0.821  1.0
  Se  Se15  1  0.250  0.989  0.901  1.0
  O  O16  1  0.250  0.372  0.030  1.0
  O  O17  1  0.750  0.872  0.470  1.0
  O  O18  1  0.250  0.128  0.530  1.0
  O  O19  1  0.750  0.628  0.970  1.0
[/CIF]
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The compound described by Sm2Se2O crystallizes in the orthorhombic Pnma space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 3-coordinate geometry to two equivalent Se(2), three equivalent Se(1), and three equivalent O(1) atoms. In the second Sm site, Sm(2) is bonded to two equivalent Se(1), three equivalent Se(2), and one O(1) atom to form a mixture of distorted edge and corner-sharing SmSe5O octahedra. The corner-sharing octahedral tilt angles are 64°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Sm(2) and three equivalent Sm(1) atoms to form distorted SeSm5 trigonal bipyramids that share corners with five equivalent O(1)Sm4 tetrahedra, edges with three 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(2) and three equivalent Sm(1) atoms to form OSm4 tetrahedra that share corners with two equivalent O(1)Sm4 tetrahedra, corners with five equivalent Se(1)Sm5 trigonal bipyramids, edges with two equivalent O(1)Sm4 tetrahedra, and edges with three equivalent Se(1)Sm5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm2Se2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.010
_cell_length_b   7.145
_cell_length_c   16.347
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   468.435
_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  0.250  0.698  0.038  1.0
  Sm  Sm1  1  0.250  0.259  0.162  1.0
  Sm  Sm2  1  0.750  0.759  0.338  1.0
  Sm  Sm3  1  0.750  0.198  0.462  1.0
  Sm  Sm4  1  0.250  0.802  0.538  1.0
  Sm  Sm5  1  0.250  0.241  0.662  1.0
  Sm  Sm6  1  0.750  0.741  0.838  1.0
  Sm  Sm7  1  0.750  0.302  0.962  1.0
  Se  Se8  1  0.750  0.011  0.099  1.0
  Se  Se9  1  0.750  0.551  0.179  1.0
  Se  Se10  1  0.250  0.051  0.321  1.0
  Se  Se11  1  0.250  0.511  0.401  1.0
  Se  Se12  1  0.750  0.489  0.599  1.0
  Se  Se13  1  0.750  0.949  0.679  1.0
  Se  Se14  1  0.250  0.449  0.821  1.0
  Se  Se15  1  0.250  0.989  0.901  1.0
  O  O16  1  0.250  0.372  0.030  1.0
  O  O17  1  0.750  0.872  0.470  1.0
  O  O18  1  0.250  0.128  0.530  1.0
  O  O19  1  0.750  0.628  0.970  1.0
[/CIF]
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