The structure described by Sm3CuSiSe7 crystallizes in the hexagonal P6_3 space group. Sm(1) is bonded in a 8-coordinate geometry to one Se(2), three equivalent Se(1), and four equivalent Se(3) atoms. Cu(1) is bonded in a trigonal planar geometry to three equivalent Se(3) atoms. Si(1) is bonded in a tetrahedral geometry to one Se(2) and three equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Sm(1) and one Si(1) atom. In the second Se site, Se(2) is bonded in a tetrahedral geometry to three equivalent Sm(1) and one Si(1) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to four equivalent Sm(1) and one Cu(1) atom. is represented by the CIF file [CIF]
data_Sm3CuSiSe7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.547
_cell_length_b   10.547
_cell_length_c   6.036
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   581.519
_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  0.645  0.772  0.742  1.0
  Sm  Sm1  1  0.228  0.873  0.742  1.0
  Sm  Sm2  1  0.355  0.228  0.242  1.0
  Sm  Sm3  1  0.873  0.645  0.242  1.0
  Sm  Sm4  1  0.127  0.355  0.742  1.0
  Sm  Sm5  1  0.772  0.127  0.242  1.0
  Cu  Cu6  1  0.000  0.000  0.723  1.0
  Cu  Cu7  1  0.000  0.000  0.223  1.0
  Si  Si8  1  0.667  0.333  0.830  1.0
  Si  Si9  1  0.333  0.667  0.330  1.0
  Se  Se10  1  0.896  0.416  0.982  1.0
  Se  Se11  1  0.667  0.333  0.454  1.0
  Se  Se12  1  0.908  0.743  0.727  1.0
  Se  Se13  1  0.835  0.092  0.727  1.0
  Se  Se14  1  0.333  0.667  0.954  1.0
  Se  Se15  1  0.257  0.165  0.727  1.0
  Se  Se16  1  0.416  0.521  0.482  1.0
  Se  Se17  1  0.743  0.835  0.227  1.0
  Se  Se18  1  0.092  0.257  0.227  1.0
  Se  Se19  1  0.479  0.896  0.482  1.0
  Se  Se20  1  0.584  0.479  0.982  1.0
  Se  Se21  1  0.165  0.908  0.227  1.0
  Se  Se22  1  0.521  0.104  0.982  1.0
  Se  Se23  1  0.104  0.584  0.482  1.0
[/CIF]
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The structure described by Sm3CuSiSe7 crystallizes in the hexagonal P6_3 space group. Sm(1) is bonded in a 8-coordinate geometry to one Se(2), three equivalent Se(1), and four equivalent Se(3) atoms. Cu(1) is bonded in a trigonal planar geometry to three equivalent Se(3) atoms. Si(1) is bonded in a tetrahedral geometry to one Se(2) and three equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Sm(1) and one Si(1) atom. In the second Se site, Se(2) is bonded in a tetrahedral geometry to three equivalent Sm(1) and one Si(1) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to four equivalent Sm(1) and one Cu(1) atom. is represented by the CIF file [CIF]
data_Sm3CuSiSe7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.547
_cell_length_b   10.547
_cell_length_c   6.036
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   581.519
_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  0.645  0.772  0.742  1.0
  Sm  Sm1  1  0.228  0.873  0.742  1.0
  Sm  Sm2  1  0.355  0.228  0.242  1.0
  Sm  Sm3  1  0.873  0.645  0.242  1.0
  Sm  Sm4  1  0.127  0.355  0.742  1.0
  Sm  Sm5  1  0.772  0.127  0.242  1.0
  Cu  Cu6  1  0.000  0.000  0.723  1.0
  Cu  Cu7  1  0.000  0.000  0.223  1.0
  Si  Si8  1  0.667  0.333  0.830  1.0
  Si  Si9  1  0.333  0.667  0.330  1.0
  Se  Se10  1  0.896  0.416  0.982  1.0
  Se  Se11  1  0.667  0.333  0.454  1.0
  Se  Se12  1  0.908  0.743  0.727  1.0
  Se  Se13  1  0.835  0.092  0.727  1.0
  Se  Se14  1  0.333  0.667  0.954  1.0
  Se  Se15  1  0.257  0.165  0.727  1.0
  Se  Se16  1  0.416  0.521  0.482  1.0
  Se  Se17  1  0.743  0.835  0.227  1.0
  Se  Se18  1  0.092  0.257  0.227  1.0
  Se  Se19  1  0.479  0.896  0.482  1.0
  Se  Se20  1  0.584  0.479  0.982  1.0
  Se  Se21  1  0.165  0.908  0.227  1.0
  Se  Se22  1  0.521  0.104  0.982  1.0
  Se  Se23  1  0.104  0.584  0.482  1.0
[/CIF]
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