The compound described by Sm2SeOF2 crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 4-coordinate geometry to four equivalent Se(1), three equivalent O(1), and one F(2) atom. In the second Sm site, Sm(2) is bonded in a 7-coordinate geometry to two equivalent Se(1), one O(1), three equivalent F(1), and three equivalent F(2) atoms. Se(1) is bonded to two equivalent Sm(2) and four equivalent Sm(1) atoms to form distorted SeSm6 pentagonal pyramids that share corners with four equivalent Se(1)Sm6 pentagonal pyramids, corners with four equivalent F(2)Sm4 tetrahedra, corners with six equivalent O(1)Sm4 tetrahedra, edges with two equivalent Se(1)Sm6 pentagonal pyramids, edges with three equivalent F(2)Sm4 tetrahedra, edges with four equivalent O(1)Sm4 tetrahedra, and faces with two equivalent Se(1)Sm6 pentagonal pyramids. O(1) is bonded to one Sm(2) and three equivalent Sm(1) atoms to form OSm4 tetrahedra that share corners with six equivalent Se(1)Sm6 pentagonal pyramids, corners with two equivalent O(1)Sm4 tetrahedra, corners with two equivalent F(2)Sm4 tetrahedra, edges with four equivalent Se(1)Sm6 pentagonal pyramids, edges with two equivalent O(1)Sm4 tetrahedra, and edges with two equivalent F(2)Sm4 tetrahedra. There are two inequivalent F sites. In the first F site, F(1) is bonded in a trigonal non-coplanar geometry to three equivalent Sm(2) atoms. In the second F site, F(2) is bonded to one Sm(1) and three equivalent Sm(2) atoms to form FSm4 tetrahedra that share corners with four equivalent Se(1)Sm6 pentagonal pyramids, corners with two equivalent O(1)Sm4 tetrahedra, corners with six equivalent F(2)Sm4 tetrahedra, edges with three equivalent Se(1)Sm6 pentagonal pyramids, and edges with two equivalent O(1)Sm4 tetrahedra. is represented by the CIF file [CIF]
data_Sm2SeOF2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.730
_cell_length_b   13.730
_cell_length_c   3.850
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   628.525
_cell_formula_units_Z   6
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  0.397  0.882  0.750  1.0
  Sm  Sm1  1  0.485  0.603  0.750  1.0
  Sm  Sm2  1  0.118  0.515  0.750  1.0
  Sm  Sm3  1  0.603  0.118  0.250  1.0
  Sm  Sm4  1  0.515  0.397  0.250  1.0
  Sm  Sm5  1  0.882  0.485  0.250  1.0
  Sm  Sm6  1  0.054  0.766  0.750  1.0
  Sm  Sm7  1  0.712  0.946  0.750  1.0
  Sm  Sm8  1  0.234  0.288  0.750  1.0
  Sm  Sm9  1  0.946  0.234  0.250  1.0
  Sm  Sm10  1  0.288  0.054  0.250  1.0
  Sm  Sm11  1  0.766  0.712  0.250  1.0
  Se  Se12  1  0.719  0.513  0.750  1.0
  Se  Se13  1  0.795  0.281  0.750  1.0
  Se  Se14  1  0.487  0.205  0.750  1.0
  Se  Se15  1  0.281  0.487  0.250  1.0
  Se  Se16  1  0.205  0.719  0.250  1.0
  Se  Se17  1  0.513  0.795  0.250  1.0
  O  O18  1  0.985  0.573  0.750  1.0
  O  O19  1  0.588  0.015  0.750  1.0
  O  O20  1  0.427  0.412  0.750  1.0
  O  O21  1  0.015  0.427  0.250  1.0
  O  O22  1  0.412  0.985  0.250  1.0
  O  O23  1  0.573  0.588  0.250  1.0
  F  F24  1  0.892  0.792  0.750  1.0
  F  F25  1  0.900  0.108  0.750  1.0
  F  F26  1  0.208  0.100  0.750  1.0
  F  F27  1  0.108  0.208  0.250  1.0
  F  F28  1  0.100  0.892  0.250  1.0
  F  F29  1  0.792  0.900  0.250  1.0
  F  F30  1  0.247  0.932  0.750  1.0
  F  F31  1  0.685  0.753  0.750  1.0
  F  F32  1  0.068  0.315  0.750  1.0
  F  F33  1  0.753  0.068  0.250  1.0
  F  F34  1  0.315  0.247  0.250  1.0
  F  F35  1  0.932  0.685  0.250  1.0
[/CIF]
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The compound described by Sm2SeOF2 crystallizes in the hexagonal P6_3/m space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 4-coordinate geometry to four equivalent Se(1), three equivalent O(1), and one F(2) atom. In the second Sm site, Sm(2) is bonded in a 7-coordinate geometry to two equivalent Se(1), one O(1), three equivalent F(1), and three equivalent F(2) atoms. Se(1) is bonded to two equivalent Sm(2) and four equivalent Sm(1) atoms to form distorted SeSm6 pentagonal pyramids that share corners with four equivalent Se(1)Sm6 pentagonal pyramids, corners with four equivalent F(2)Sm4 tetrahedra, corners with six equivalent O(1)Sm4 tetrahedra, edges with two equivalent Se(1)Sm6 pentagonal pyramids, edges with three equivalent F(2)Sm4 tetrahedra, edges with four equivalent O(1)Sm4 tetrahedra, and faces with two equivalent Se(1)Sm6 pentagonal pyramids. O(1) is bonded to one Sm(2) and three equivalent Sm(1) atoms to form OSm4 tetrahedra that share corners with six equivalent Se(1)Sm6 pentagonal pyramids, corners with two equivalent O(1)Sm4 tetrahedra, corners with two equivalent F(2)Sm4 tetrahedra, edges with four equivalent Se(1)Sm6 pentagonal pyramids, edges with two equivalent O(1)Sm4 tetrahedra, and edges with two equivalent F(2)Sm4 tetrahedra. There are two inequivalent F sites. In the first F site, F(1) is bonded in a trigonal non-coplanar geometry to three equivalent Sm(2) atoms. In the second F site, F(2) is bonded to one Sm(1) and three equivalent Sm(2) atoms to form FSm4 tetrahedra that share corners with four equivalent Se(1)Sm6 pentagonal pyramids, corners with two equivalent O(1)Sm4 tetrahedra, corners with six equivalent F(2)Sm4 tetrahedra, edges with three equivalent Se(1)Sm6 pentagonal pyramids, and edges with two equivalent O(1)Sm4 tetrahedra. is represented by the CIF file [CIF]
data_Sm2SeOF2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.730
_cell_length_b   13.730
_cell_length_c   3.850
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   628.525
_cell_formula_units_Z   6
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  0.397  0.882  0.750  1.0
  Sm  Sm1  1  0.485  0.603  0.750  1.0
  Sm  Sm2  1  0.118  0.515  0.750  1.0
  Sm  Sm3  1  0.603  0.118  0.250  1.0
  Sm  Sm4  1  0.515  0.397  0.250  1.0
  Sm  Sm5  1  0.882  0.485  0.250  1.0
  Sm  Sm6  1  0.054  0.766  0.750  1.0
  Sm  Sm7  1  0.712  0.946  0.750  1.0
  Sm  Sm8  1  0.234  0.288  0.750  1.0
  Sm  Sm9  1  0.946  0.234  0.250  1.0
  Sm  Sm10  1  0.288  0.054  0.250  1.0
  Sm  Sm11  1  0.766  0.712  0.250  1.0
  Se  Se12  1  0.719  0.513  0.750  1.0
  Se  Se13  1  0.795  0.281  0.750  1.0
  Se  Se14  1  0.487  0.205  0.750  1.0
  Se  Se15  1  0.281  0.487  0.250  1.0
  Se  Se16  1  0.205  0.719  0.250  1.0
  Se  Se17  1  0.513  0.795  0.250  1.0
  O  O18  1  0.985  0.573  0.750  1.0
  O  O19  1  0.588  0.015  0.750  1.0
  O  O20  1  0.427  0.412  0.750  1.0
  O  O21  1  0.015  0.427  0.250  1.0
  O  O22  1  0.412  0.985  0.250  1.0
  O  O23  1  0.573  0.588  0.250  1.0
  F  F24  1  0.892  0.792  0.750  1.0
  F  F25  1  0.900  0.108  0.750  1.0
  F  F26  1  0.208  0.100  0.750  1.0
  F  F27  1  0.108  0.208  0.250  1.0
  F  F28  1  0.100  0.892  0.250  1.0
  F  F29  1  0.792  0.900  0.250  1.0
  F  F30  1  0.247  0.932  0.750  1.0
  F  F31  1  0.685  0.753  0.750  1.0
  F  F32  1  0.068  0.315  0.750  1.0
  F  F33  1  0.753  0.068  0.250  1.0
  F  F34  1  0.315  0.247  0.250  1.0
  F  F35  1  0.932  0.685  0.250  1.0
[/CIF]
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