The material structure described by Na6FeSe4 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted NaSe4 tetrahedra that share corners with two equivalent Fe(1)Se4 tetrahedra, corners with eight equivalent Na(1)Se4 tetrahedra, and  an edgeedge with one Fe(1)Se4 tetrahedra. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one Se(1) and four equivalent Se(2) atoms. Fe(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted FeSe4 tetrahedra that share corners with six equivalent Na(1)Se4 tetrahedra and edges with three equivalent Na(1)Se4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to three equivalent Na(1), three equivalent Na(2), and one Fe(1) atom. In the second Se site, Se(2) is bonded in a 8-coordinate geometry to three equivalent Na(1), four equivalent Na(2), and one Fe(1) atom. is represented by the CIF card [CIF]
data_Na6FeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.358
_cell_length_b   9.358
_cell_length_c   7.239
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   548.977
_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  0.148  0.852  0.542  1.0
  Na  Na1  1  0.296  0.148  0.042  1.0
  Na  Na2  1  0.852  0.704  0.042  1.0
  Na  Na3  1  0.148  0.296  0.542  1.0
  Na  Na4  1  0.704  0.852  0.542  1.0
  Na  Na5  1  0.852  0.148  0.042  1.0
  Na  Na6  1  0.530  0.470  0.370  1.0
  Na  Na7  1  0.060  0.530  0.870  1.0
  Na  Na8  1  0.470  0.940  0.870  1.0
  Na  Na9  1  0.530  0.060  0.370  1.0
  Na  Na10  1  0.940  0.470  0.370  1.0
  Na  Na11  1  0.470  0.530  0.870  1.0
  Fe  Fe12  1  0.333  0.667  0.253  1.0
  Fe  Fe13  1  0.667  0.333  0.753  1.0
  Se  Se14  1  0.333  0.667  0.596  1.0
  Se  Se15  1  0.667  0.333  0.096  1.0
  Se  Se16  1  0.188  0.812  0.145  1.0
  Se  Se17  1  0.376  0.188  0.645  1.0
  Se  Se18  1  0.812  0.624  0.645  1.0
  Se  Se19  1  0.188  0.376  0.145  1.0
  Se  Se20  1  0.624  0.812  0.145  1.0
  Se  Se21  1  0.812  0.188  0.645  1.0
[/CIF]
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The material structure described by Na6FeSe4 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted NaSe4 tetrahedra that share corners with two equivalent Fe(1)Se4 tetrahedra, corners with eight equivalent Na(1)Se4 tetrahedra, and  an edgeedge with one Fe(1)Se4 tetrahedra. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one Se(1) and four equivalent Se(2) atoms. Fe(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted FeSe4 tetrahedra that share corners with six equivalent Na(1)Se4 tetrahedra and edges with three equivalent Na(1)Se4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to three equivalent Na(1), three equivalent Na(2), and one Fe(1) atom. In the second Se site, Se(2) is bonded in a 8-coordinate geometry to three equivalent Na(1), four equivalent Na(2), and one Fe(1) atom. is represented by the CIF card [CIF]
data_Na6FeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.358
_cell_length_b   9.358
_cell_length_c   7.239
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   548.977
_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  0.148  0.852  0.542  1.0
  Na  Na1  1  0.296  0.148  0.042  1.0
  Na  Na2  1  0.852  0.704  0.042  1.0
  Na  Na3  1  0.148  0.296  0.542  1.0
  Na  Na4  1  0.704  0.852  0.542  1.0
  Na  Na5  1  0.852  0.148  0.042  1.0
  Na  Na6  1  0.530  0.470  0.370  1.0
  Na  Na7  1  0.060  0.530  0.870  1.0
  Na  Na8  1  0.470  0.940  0.870  1.0
  Na  Na9  1  0.530  0.060  0.370  1.0
  Na  Na10  1  0.940  0.470  0.370  1.0
  Na  Na11  1  0.470  0.530  0.870  1.0
  Fe  Fe12  1  0.333  0.667  0.253  1.0
  Fe  Fe13  1  0.667  0.333  0.753  1.0
  Se  Se14  1  0.333  0.667  0.596  1.0
  Se  Se15  1  0.667  0.333  0.096  1.0
  Se  Se16  1  0.188  0.812  0.145  1.0
  Se  Se17  1  0.376  0.188  0.645  1.0
  Se  Se18  1  0.812  0.624  0.645  1.0
  Se  Se19  1  0.188  0.376  0.145  1.0
  Se  Se20  1  0.624  0.812  0.145  1.0
  Se  Se21  1  0.812  0.188  0.645  1.0
[/CIF]
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