The crystal structure described by Na1Mo6Se8 crystallizes in the trigonal R-3 space group. Na(1) is bonded in a body-centered cubic geometry to two equivalent Se(2) and six equivalent Se(1) atoms. Mo(1) is bonded to one Se(2) and four equivalent Se(1) atoms to form a mixture of distorted corner and edge-sharing MoSe5 square pyramids. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a 4-coordinate geometry to one Na(1) and three equivalent Mo(1) atoms. In the second Se site, Se(1) is bonded to one Na(1) and four equivalent Mo(1) atoms to form a mixture of distorted corner and edge-sharing SeNaMo4 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na(Mo3Se4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.836
_cell_length_b   6.836
_cell_length_c   6.836
_cell_angle_alpha   89.777
_cell_angle_beta   89.777
_cell_angle_gamma   89.777
_symmetry_Int_Tables_number   1
_cell_volume   319.472
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Mo  Mo1  1  0.765  0.444  0.579  1.0
  Mo  Mo2  1  0.579  0.765  0.444  1.0
  Mo  Mo3  1  0.444  0.579  0.765  1.0
  Mo  Mo4  1  0.235  0.556  0.421  1.0
  Mo  Mo5  1  0.421  0.235  0.556  1.0
  Mo  Mo6  1  0.556  0.421  0.235  1.0
  Se  Se7  1  0.876  0.617  0.253  1.0
  Se  Se8  1  0.253  0.876  0.617  1.0
  Se  Se9  1  0.617  0.253  0.876  1.0
  Se  Se10  1  0.124  0.383  0.747  1.0
  Se  Se11  1  0.747  0.124  0.383  1.0
  Se  Se12  1  0.383  0.747  0.124  1.0
  Se  Se13  1  0.764  0.764  0.764  1.0
  Se  Se14  1  0.236  0.236  0.236  1.0
[/CIF]
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The crystal structure described by Na1Mo6Se8 crystallizes in the trigonal R-3 space group. Na(1) is bonded in a body-centered cubic geometry to two equivalent Se(2) and six equivalent Se(1) atoms. Mo(1) is bonded to one Se(2) and four equivalent Se(1) atoms to form a mixture of distorted corner and edge-sharing MoSe5 square pyramids. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a 4-coordinate geometry to one Na(1) and three equivalent Mo(1) atoms. In the second Se site, Se(1) is bonded to one Na(1) and four equivalent Mo(1) atoms to form a mixture of distorted corner and edge-sharing SeNaMo4 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na(Mo3Se4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.836
_cell_length_b   6.836
_cell_length_c   6.836
_cell_angle_alpha   89.777
_cell_angle_beta   89.777
_cell_angle_gamma   89.777
_symmetry_Int_Tables_number   1
_cell_volume   319.472
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Mo  Mo1  1  0.765  0.444  0.579  1.0
  Mo  Mo2  1  0.579  0.765  0.444  1.0
  Mo  Mo3  1  0.444  0.579  0.765  1.0
  Mo  Mo4  1  0.235  0.556  0.421  1.0
  Mo  Mo5  1  0.421  0.235  0.556  1.0
  Mo  Mo6  1  0.556  0.421  0.235  1.0
  Se  Se7  1  0.876  0.617  0.253  1.0
  Se  Se8  1  0.253  0.876  0.617  1.0
  Se  Se9  1  0.617  0.253  0.876  1.0
  Se  Se10  1  0.124  0.383  0.747  1.0
  Se  Se11  1  0.747  0.124  0.383  1.0
  Se  Se12  1  0.383  0.747  0.124  1.0
  Se  Se13  1  0.764  0.764  0.764  1.0
  Se  Se14  1  0.236  0.236  0.236  1.0
[/CIF]
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