The compound described by Na4SnSe4 crystallizes in the tetragonal P-42_1c space group. Na(1) is bonded to five equivalent Se(1) atoms to form distorted NaSe5 trigonal bipyramids that share corners with three equivalent Sn(1)Se4 tetrahedra, corners with ten equivalent Na(1)Se5 trigonal bipyramids,  an edgeedge with one Sn(1)Se4 tetrahedra, and edges with five equivalent Na(1)Se5 trigonal bipyramids. Sn(1) is bonded to four equivalent Se(1) atoms to form SnSe4 tetrahedra that share corners with twelve equivalent Na(1)Se5 trigonal bipyramids and edges with four equivalent Na(1)Se5 trigonal bipyramids. Se(1) is bonded in a 6-coordinate geometry to five equivalent Na(1) and one Sn(1) atom. is represented by the CIF file [CIF]
data_Na4SnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.283
_cell_length_b   8.164
_cell_length_c   8.164
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   485.419
_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
  Na  Na0  1  0.028  0.197  0.595  1.0
  Na  Na1  1  0.972  0.595  0.803  1.0
  Na  Na2  1  0.972  0.405  0.197  1.0
  Na  Na3  1  0.028  0.803  0.405  1.0
  Na  Na4  1  0.472  0.697  0.905  1.0
  Na  Na5  1  0.472  0.303  0.095  1.0
  Na  Na6  1  0.528  0.905  0.303  1.0
  Na  Na7  1  0.528  0.095  0.697  1.0
  Sn  Sn8  1  0.000  0.000  0.000  1.0
  Sn  Sn9  1  0.500  0.500  0.500  1.0
  Se  Se10  1  0.691  0.257  0.405  1.0
  Se  Se11  1  0.691  0.743  0.595  1.0
  Se  Se12  1  0.191  0.095  0.243  1.0
  Se  Se13  1  0.809  0.243  0.905  1.0
  Se  Se14  1  0.809  0.757  0.095  1.0
  Se  Se15  1  0.191  0.905  0.757  1.0
  Se  Se16  1  0.309  0.595  0.257  1.0
  Se  Se17  1  0.309  0.405  0.743  1.0
[/CIF]
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The compound described by Na4SnSe4 crystallizes in the tetragonal P-42_1c space group. Na(1) is bonded to five equivalent Se(1) atoms to form distorted NaSe5 trigonal bipyramids that share corners with three equivalent Sn(1)Se4 tetrahedra, corners with ten equivalent Na(1)Se5 trigonal bipyramids,  an edgeedge with one Sn(1)Se4 tetrahedra, and edges with five equivalent Na(1)Se5 trigonal bipyramids. Sn(1) is bonded to four equivalent Se(1) atoms to form SnSe4 tetrahedra that share corners with twelve equivalent Na(1)Se5 trigonal bipyramids and edges with four equivalent Na(1)Se5 trigonal bipyramids. Se(1) is bonded in a 6-coordinate geometry to five equivalent Na(1) and one Sn(1) atom. is represented by the CIF file [CIF]
data_Na4SnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.283
_cell_length_b   8.164
_cell_length_c   8.164
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   485.419
_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
  Na  Na0  1  0.028  0.197  0.595  1.0
  Na  Na1  1  0.972  0.595  0.803  1.0
  Na  Na2  1  0.972  0.405  0.197  1.0
  Na  Na3  1  0.028  0.803  0.405  1.0
  Na  Na4  1  0.472  0.697  0.905  1.0
  Na  Na5  1  0.472  0.303  0.095  1.0
  Na  Na6  1  0.528  0.905  0.303  1.0
  Na  Na7  1  0.528  0.095  0.697  1.0
  Sn  Sn8  1  0.000  0.000  0.000  1.0
  Sn  Sn9  1  0.500  0.500  0.500  1.0
  Se  Se10  1  0.691  0.257  0.405  1.0
  Se  Se11  1  0.691  0.743  0.595  1.0
  Se  Se12  1  0.191  0.095  0.243  1.0
  Se  Se13  1  0.809  0.243  0.905  1.0
  Se  Se14  1  0.809  0.757  0.095  1.0
  Se  Se15  1  0.191  0.905  0.757  1.0
  Se  Se16  1  0.309  0.595  0.257  1.0
  Se  Se17  1  0.309  0.405  0.743  1.0
[/CIF]
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