The structure described by NaAsSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal I4_1/amd space group. Na(1) is bonded to six Se(1,1) atoms to form NaSe6 octahedra that share corners with two equivalent As(1)Se6 octahedra, corners with four equivalent Na(1)Se6 octahedra, edges with four equivalent Na(1)Se6 octahedra, and edges with eight equivalent As(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. As(1) is bonded to six equivalent Se(1) atoms to form AsSe6 octahedra that share corners with two equivalent Na(1)Se6 octahedra, corners with four equivalent As(1)Se6 octahedra, edges with four equivalent As(1)Se6 octahedra, and edges with eight equivalent Na(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Na(1) and three equivalent As(1) atoms to form a mixture of edge and corner-sharing SeNa3As3 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the second Se site, Se(1) is bonded to three equivalent Na(1) and three equivalent As(1) atoms to form a mixture of edge and corner-sharing SeNa3As3 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the third Se site, Se(1) is bonded to three equivalent Na(1) and three equivalent As(1) atoms to form a mixture of edge and corner-sharing SeNa3As3 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. is represented by the CIF card [CIF]
data_NaAsSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.086
_cell_length_b   7.086
_cell_length_c   7.086
_cell_angle_alpha   133.510
_cell_angle_beta   133.510
_cell_angle_gamma   67.854
_symmetry_Int_Tables_number   1
_cell_volume   183.919
_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  0.000  0.000  0.000  1.0
  Na  Na1  1  0.750  0.250  0.500  1.0
  As  As2  1  0.250  0.750  0.500  1.0
  As  As3  1  0.500  0.500  0.000  1.0
  Se  Se4  1  0.481  0.981  0.500  1.0
  Se  Se5  1  0.019  0.519  0.500  1.0
  Se  Se6  1  0.731  0.731  0.000  1.0
  Se  Se7  1  0.269  0.269  0.000  1.0
[/CIF]
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The structure described by NaAsSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal I4_1/amd space group. Na(1) is bonded to six Se(1,1) atoms to form NaSe6 octahedra that share corners with two equivalent As(1)Se6 octahedra, corners with four equivalent Na(1)Se6 octahedra, edges with four equivalent Na(1)Se6 octahedra, and edges with eight equivalent As(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. As(1) is bonded to six equivalent Se(1) atoms to form AsSe6 octahedra that share corners with two equivalent Na(1)Se6 octahedra, corners with four equivalent As(1)Se6 octahedra, edges with four equivalent As(1)Se6 octahedra, and edges with eight equivalent Na(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Na(1) and three equivalent As(1) atoms to form a mixture of edge and corner-sharing SeNa3As3 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the second Se site, Se(1) is bonded to three equivalent Na(1) and three equivalent As(1) atoms to form a mixture of edge and corner-sharing SeNa3As3 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the third Se site, Se(1) is bonded to three equivalent Na(1) and three equivalent As(1) atoms to form a mixture of edge and corner-sharing SeNa3As3 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. is represented by the CIF card [CIF]
data_NaAsSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.086
_cell_length_b   7.086
_cell_length_c   7.086
_cell_angle_alpha   133.510
_cell_angle_beta   133.510
_cell_angle_gamma   67.854
_symmetry_Int_Tables_number   1
_cell_volume   183.919
_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  0.000  0.000  0.000  1.0
  Na  Na1  1  0.750  0.250  0.500  1.0
  As  As2  1  0.250  0.750  0.500  1.0
  As  As3  1  0.500  0.500  0.000  1.0
  Se  Se4  1  0.481  0.981  0.500  1.0
  Se  Se5  1  0.019  0.519  0.500  1.0
  Se  Se6  1  0.731  0.731  0.000  1.0
  Se  Se7  1  0.269  0.269  0.000  1.0
[/CIF]
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