The crystal structure described by Sm5Se9 crystallizes in the triclinic P-1 space group. There are five inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 9-coordinate geometry to one Se(1), one Se(2), one Se(3), one Se(4), one Se(5), one Se(6), one Se(8), and two equivalent Se(7) atoms. In the second Sm site, Sm(2) is bonded in a 8-coordinate geometry to one Se(2), one Se(3), one Se(7), one Se(9), two equivalent Se(1), and two equivalent Se(4) atoms. In the third Sm site, Sm(3) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), one Se(5), one Se(8), two equivalent Se(6), and two equivalent Se(9) atoms. In the fourth Sm site, Sm(4) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), one Se(6), one Se(7), one Se(8), one Se(9), and two equivalent Se(2) atoms. In the fifth Sm site, Sm(5) is bonded in a 8-coordinate geometry to one Se(1), one Se(3), one Se(7), one Se(9), two equivalent Se(5), and two equivalent Se(8) atoms. There are nine inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(5), two equivalent Sm(2), and one Se(1) atom. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one Sm(1), one Sm(2), and two equivalent Sm(4) atoms. In the third Se site, Se(3) is bonded to one Sm(1), one Sm(2), one Sm(3), one Sm(4), and one Sm(5) atom to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to one Sm(1), one Sm(3), one Sm(4), and two equivalent Sm(2) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(3), two equivalent Sm(5), and one Se(5) atom. In the sixth Se site, Se(6) is bonded in a 4-coordinate geometry to one Sm(1), one Sm(4), and two equivalent Sm(3) atoms. In the seventh Se site, Se(7) is bonded to one Sm(2), one Sm(4), one Sm(5), and two equivalent Sm(1) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. In the eighth Se site, Se(8) is bonded to one Sm(1), one Sm(3), one Sm(4), and two equivalent Sm(5) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. In the ninth Se site, Se(9) is bonded to one Sm(2), one Sm(4), one Sm(5), and two equivalent Sm(3) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Sm5Se9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.105
_cell_length_b   9.258
_cell_length_c   9.349
_cell_angle_alpha   112.789
_cell_angle_beta   101.021
_cell_angle_gamma   90.429
_symmetry_Int_Tables_number   1
_cell_volume   710.309
_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  0.695  0.637  0.741  1.0
  Sm  Sm1  1  0.305  0.363  0.259  1.0
  Sm  Sm2  1  0.485  0.238  0.721  1.0
  Sm  Sm3  1  0.104  0.961  0.275  1.0
  Sm  Sm4  1  0.306  0.852  0.739  1.0
  Sm  Sm5  1  0.907  0.565  0.286  1.0
  Sm  Sm6  1  0.093  0.435  0.714  1.0
  Sm  Sm7  1  0.694  0.148  0.261  1.0
  Sm  Sm8  1  0.896  0.039  0.725  1.0
  Sm  Sm9  1  0.515  0.762  0.279  1.0
  Se  Se10  1  0.637  0.508  0.996  1.0
  Se  Se11  1  0.455  0.160  0.998  1.0
  Se  Se12  1  0.545  0.840  0.002  1.0
  Se  Se13  1  0.771  0.296  0.631  1.0
  Se  Se14  1  0.363  0.492  0.004  1.0
  Se  Se15  1  0.418  0.092  0.360  1.0
  Se  Se16  1  0.582  0.908  0.640  1.0
  Se  Se17  1  0.037  0.369  1.000  1.0
  Se  Se18  1  0.140  0.046  0.000  1.0
  Se  Se19  1  0.229  0.704  0.369  1.0
  Se  Se20  1  0.860  0.954  1.000  1.0
  Se  Se21  1  0.372  0.504  0.626  1.0
  Se  Se22  1  0.015  0.295  0.358  1.0
  Se  Se23  1  0.963  0.631  0.000  1.0
  Se  Se24  1  0.172  0.105  0.631  1.0
  Se  Se25  1  0.828  0.895  0.369  1.0
  Se  Se26  1  0.985  0.705  0.642  1.0
  Se  Se27  1  0.628  0.496  0.374  1.0
[/CIF]
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The crystal structure described by Sm5Se9 crystallizes in the triclinic P-1 space group. There are five inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 9-coordinate geometry to one Se(1), one Se(2), one Se(3), one Se(4), one Se(5), one Se(6), one Se(8), and two equivalent Se(7) atoms. In the second Sm site, Sm(2) is bonded in a 8-coordinate geometry to one Se(2), one Se(3), one Se(7), one Se(9), two equivalent Se(1), and two equivalent Se(4) atoms. In the third Sm site, Sm(3) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), one Se(5), one Se(8), two equivalent Se(6), and two equivalent Se(9) atoms. In the fourth Sm site, Sm(4) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), one Se(6), one Se(7), one Se(8), one Se(9), and two equivalent Se(2) atoms. In the fifth Sm site, Sm(5) is bonded in a 8-coordinate geometry to one Se(1), one Se(3), one Se(7), one Se(9), two equivalent Se(5), and two equivalent Se(8) atoms. There are nine inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(5), two equivalent Sm(2), and one Se(1) atom. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one Sm(1), one Sm(2), and two equivalent Sm(4) atoms. In the third Se site, Se(3) is bonded to one Sm(1), one Sm(2), one Sm(3), one Sm(4), and one Sm(5) atom to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to one Sm(1), one Sm(3), one Sm(4), and two equivalent Sm(2) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(3), two equivalent Sm(5), and one Se(5) atom. In the sixth Se site, Se(6) is bonded in a 4-coordinate geometry to one Sm(1), one Sm(4), and two equivalent Sm(3) atoms. In the seventh Se site, Se(7) is bonded to one Sm(2), one Sm(4), one Sm(5), and two equivalent Sm(1) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. In the eighth Se site, Se(8) is bonded to one Sm(1), one Sm(3), one Sm(4), and two equivalent Sm(5) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. In the ninth Se site, Se(9) is bonded to one Sm(2), one Sm(4), one Sm(5), and two equivalent Sm(3) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Sm5Se9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.105
_cell_length_b   9.258
_cell_length_c   9.349
_cell_angle_alpha   112.789
_cell_angle_beta   101.021
_cell_angle_gamma   90.429
_symmetry_Int_Tables_number   1
_cell_volume   710.309
_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  0.695  0.637  0.741  1.0
  Sm  Sm1  1  0.305  0.363  0.259  1.0
  Sm  Sm2  1  0.485  0.238  0.721  1.0
  Sm  Sm3  1  0.104  0.961  0.275  1.0
  Sm  Sm4  1  0.306  0.852  0.739  1.0
  Sm  Sm5  1  0.907  0.565  0.286  1.0
  Sm  Sm6  1  0.093  0.435  0.714  1.0
  Sm  Sm7  1  0.694  0.148  0.261  1.0
  Sm  Sm8  1  0.896  0.039  0.725  1.0
  Sm  Sm9  1  0.515  0.762  0.279  1.0
  Se  Se10  1  0.637  0.508  0.996  1.0
  Se  Se11  1  0.455  0.160  0.998  1.0
  Se  Se12  1  0.545  0.840  0.002  1.0
  Se  Se13  1  0.771  0.296  0.631  1.0
  Se  Se14  1  0.363  0.492  0.004  1.0
  Se  Se15  1  0.418  0.092  0.360  1.0
  Se  Se16  1  0.582  0.908  0.640  1.0
  Se  Se17  1  0.037  0.369  1.000  1.0
  Se  Se18  1  0.140  0.046  0.000  1.0
  Se  Se19  1  0.229  0.704  0.369  1.0
  Se  Se20  1  0.860  0.954  1.000  1.0
  Se  Se21  1  0.372  0.504  0.626  1.0
  Se  Se22  1  0.015  0.295  0.358  1.0
  Se  Se23  1  0.963  0.631  0.000  1.0
  Se  Se24  1  0.172  0.105  0.631  1.0
  Se  Se25  1  0.828  0.895  0.369  1.0
  Se  Se26  1  0.985  0.705  0.642  1.0
  Se  Se27  1  0.628  0.496  0.374  1.0
[/CIF]
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