The crystal structure described by Na2TeSe3 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing NaSe6 octahedra. The corner-sharing octahedral tilt angles range from 8-11°. In the second Na site, Na(2) is bonded to one Se(1), two equivalent Se(2), and three equivalent Se(3) atoms to form a mixture of corner and edge-sharing NaSe6 octahedra. The corner-sharing octahedral tilt angles range from 5-11°. Te(1) is bonded in a trigonal non-coplanar geometry to one Se(1), one Se(2), and one Se(3) atom. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one Te(1) atom. In the second Se site, Se(2) is bonded to two equivalent Na(1), two equivalent Na(2), and one Te(1) atom to form SeNa4Te square pyramids that share  a cornercorner with one Se(3)Na5Te octahedra, corners with four equivalent Se(2)Na4Te square pyramids, and edges with five equivalent Se(3)Na5Te octahedra. The corner-sharing octahedral tilt angles are 7°. In the third Se site, Se(3) is bonded to two equivalent Na(1), three equivalent Na(2), and one Te(1) atom to form SeNa5Te octahedra that share corners with four equivalent Se(3)Na5Te octahedra,  a cornercorner with one Se(2)Na4Te square pyramid, edges with two equivalent Se(3)Na5Te octahedra, and edges with five equivalent Se(2)Na4Te square pyramids. The corner-sharing octahedral tilt angles range from 3-7°. is represented by the CIF file [CIF]
data_Na2TeSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.959
_cell_length_b   8.768
_cell_length_c   12.607
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   93.666
_symmetry_Int_Tables_number   1
_cell_volume   657.305
_cell_formula_units_Z   4
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  0.264  0.367  0.262  1.0
  Na  Na1  1  0.736  0.133  0.762  1.0
  Na  Na2  1  0.736  0.633  0.738  1.0
  Na  Na3  1  0.264  0.867  0.238  1.0
  Na  Na4  1  0.754  0.136  0.417  1.0
  Na  Na5  1  0.246  0.364  0.917  1.0
  Na  Na6  1  0.246  0.864  0.583  1.0
  Na  Na7  1  0.754  0.636  0.083  1.0
  Te  Te8  1  0.298  0.309  0.589  1.0
  Te  Te9  1  0.702  0.191  0.089  1.0
  Te  Te10  1  0.702  0.691  0.411  1.0
  Te  Te11  1  0.298  0.809  0.911  1.0
  Se  Se12  1  0.719  0.368  0.592  1.0
  Se  Se13  1  0.281  0.132  0.092  1.0
  Se  Se14  1  0.281  0.632  0.408  1.0
  Se  Se15  1  0.719  0.868  0.908  1.0
  Se  Se16  1  0.236  0.122  0.741  1.0
  Se  Se17  1  0.764  0.378  0.241  1.0
  Se  Se18  1  0.764  0.878  0.259  1.0
  Se  Se19  1  0.236  0.622  0.759  1.0
  Se  Se20  1  0.252  0.136  0.431  1.0
  Se  Se21  1  0.748  0.364  0.931  1.0
  Se  Se22  1  0.748  0.864  0.569  1.0
  Se  Se23  1  0.252  0.636  0.069  1.0
[/CIF]
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The crystal structure described by Na2TeSe3 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing NaSe6 octahedra. The corner-sharing octahedral tilt angles range from 8-11°. In the second Na site, Na(2) is bonded to one Se(1), two equivalent Se(2), and three equivalent Se(3) atoms to form a mixture of corner and edge-sharing NaSe6 octahedra. The corner-sharing octahedral tilt angles range from 5-11°. Te(1) is bonded in a trigonal non-coplanar geometry to one Se(1), one Se(2), and one Se(3) atom. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to one Na(2), two equivalent Na(1), and one Te(1) atom. In the second Se site, Se(2) is bonded to two equivalent Na(1), two equivalent Na(2), and one Te(1) atom to form SeNa4Te square pyramids that share  a cornercorner with one Se(3)Na5Te octahedra, corners with four equivalent Se(2)Na4Te square pyramids, and edges with five equivalent Se(3)Na5Te octahedra. The corner-sharing octahedral tilt angles are 7°. In the third Se site, Se(3) is bonded to two equivalent Na(1), three equivalent Na(2), and one Te(1) atom to form SeNa5Te octahedra that share corners with four equivalent Se(3)Na5Te octahedra,  a cornercorner with one Se(2)Na4Te square pyramid, edges with two equivalent Se(3)Na5Te octahedra, and edges with five equivalent Se(2)Na4Te square pyramids. The corner-sharing octahedral tilt angles range from 3-7°. is represented by the CIF file [CIF]
data_Na2TeSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.959
_cell_length_b   8.768
_cell_length_c   12.607
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   93.666
_symmetry_Int_Tables_number   1
_cell_volume   657.305
_cell_formula_units_Z   4
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  0.264  0.367  0.262  1.0
  Na  Na1  1  0.736  0.133  0.762  1.0
  Na  Na2  1  0.736  0.633  0.738  1.0
  Na  Na3  1  0.264  0.867  0.238  1.0
  Na  Na4  1  0.754  0.136  0.417  1.0
  Na  Na5  1  0.246  0.364  0.917  1.0
  Na  Na6  1  0.246  0.864  0.583  1.0
  Na  Na7  1  0.754  0.636  0.083  1.0
  Te  Te8  1  0.298  0.309  0.589  1.0
  Te  Te9  1  0.702  0.191  0.089  1.0
  Te  Te10  1  0.702  0.691  0.411  1.0
  Te  Te11  1  0.298  0.809  0.911  1.0
  Se  Se12  1  0.719  0.368  0.592  1.0
  Se  Se13  1  0.281  0.132  0.092  1.0
  Se  Se14  1  0.281  0.632  0.408  1.0
  Se  Se15  1  0.719  0.868  0.908  1.0
  Se  Se16  1  0.236  0.122  0.741  1.0
  Se  Se17  1  0.764  0.378  0.241  1.0
  Se  Se18  1  0.764  0.878  0.259  1.0
  Se  Se19  1  0.236  0.622  0.759  1.0
  Se  Se20  1  0.252  0.136  0.431  1.0
  Se  Se21  1  0.748  0.364  0.931  1.0
  Se  Se22  1  0.748  0.864  0.569  1.0
  Se  Se23  1  0.252  0.636  0.069  1.0
[/CIF]
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