The structure described by Na6CoSe4 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 Co(1)Se4 tetrahedra, corners with eight equivalent Na(1)Se4 tetrahedra, and  an edgeedge with one Co(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. Co(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted CoSe4 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 Co(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 Co(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na6CoSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.326
_cell_length_b   9.326
_cell_length_c   7.208
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   542.944
_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  0.533  1.0
  Na  Na1  1  0.297  0.148  0.033  1.0
  Na  Na2  1  0.852  0.703  0.033  1.0
  Na  Na3  1  0.148  0.297  0.533  1.0
  Na  Na4  1  0.703  0.852  0.533  1.0
  Na  Na5  1  0.852  0.148  0.033  1.0
  Na  Na6  1  0.529  0.471  0.359  1.0
  Na  Na7  1  0.058  0.529  0.859  1.0
  Na  Na8  1  0.471  0.942  0.859  1.0
  Na  Na9  1  0.529  0.058  0.359  1.0
  Na  Na10  1  0.942  0.471  0.359  1.0
  Na  Na11  1  0.471  0.529  0.859  1.0
  Co  Co12  1  0.333  0.667  0.244  1.0
  Co  Co13  1  0.667  0.333  0.744  1.0
  Se  Se14  1  0.333  0.667  0.583  1.0
  Se  Se15  1  0.667  0.333  0.083  1.0
  Se  Se16  1  0.189  0.811  0.136  1.0
  Se  Se17  1  0.379  0.189  0.636  1.0
  Se  Se18  1  0.811  0.621  0.636  1.0
  Se  Se19  1  0.189  0.379  0.136  1.0
  Se  Se20  1  0.621  0.811  0.136  1.0
  Se  Se21  1  0.811  0.189  0.636  1.0
[/CIF]
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The structure described by Na6CoSe4 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 Co(1)Se4 tetrahedra, corners with eight equivalent Na(1)Se4 tetrahedra, and  an edgeedge with one Co(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. Co(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted CoSe4 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 Co(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 Co(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na6CoSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.326
_cell_length_b   9.326
_cell_length_c   7.208
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   542.944
_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  0.533  1.0
  Na  Na1  1  0.297  0.148  0.033  1.0
  Na  Na2  1  0.852  0.703  0.033  1.0
  Na  Na3  1  0.148  0.297  0.533  1.0
  Na  Na4  1  0.703  0.852  0.533  1.0
  Na  Na5  1  0.852  0.148  0.033  1.0
  Na  Na6  1  0.529  0.471  0.359  1.0
  Na  Na7  1  0.058  0.529  0.859  1.0
  Na  Na8  1  0.471  0.942  0.859  1.0
  Na  Na9  1  0.529  0.058  0.359  1.0
  Na  Na10  1  0.942  0.471  0.359  1.0
  Na  Na11  1  0.471  0.529  0.859  1.0
  Co  Co12  1  0.333  0.667  0.244  1.0
  Co  Co13  1  0.667  0.333  0.744  1.0
  Se  Se14  1  0.333  0.667  0.583  1.0
  Se  Se15  1  0.667  0.333  0.083  1.0
  Se  Se16  1  0.189  0.811  0.136  1.0
  Se  Se17  1  0.379  0.189  0.636  1.0
  Se  Se18  1  0.811  0.621  0.636  1.0
  Se  Se19  1  0.189  0.379  0.136  1.0
  Se  Se20  1  0.621  0.811  0.136  1.0
  Se  Se21  1  0.811  0.189  0.636  1.0
[/CIF]
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