The crystal structure described by NaAsSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. Na(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form NaSe6 octahedra that share corners with six 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 octahedra are not tilted. As(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form AsSe6 octahedra that share corners with six 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 octahedra are not tilted. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Na(1) and four equivalent As(1) atoms to form SeNa2As4 octahedra that share corners with six equivalent Se(1)Na2As4 octahedra, edges with four equivalent Se(1)Na2As4 octahedra, and edges with eight equivalent Se(2)Na4As2 octahedra. The corner-sharing octahedra are not tilted. In the second Se site, Se(2) is bonded to four equivalent Na(1) and two equivalent As(1) atoms to form SeNa4As2 octahedra that share corners with six equivalent Se(2)Na4As2 octahedra, edges with four equivalent Se(2)Na4As2 octahedra, and edges with eight equivalent Se(1)Na2As4 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaAsSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.001
_cell_length_b   4.001
_cell_length_c   5.568
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   89.141
_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
  As  As1  1  0.500  0.500  0.500  1.0
  Se  Se2  1  0.000  0.000  0.500  1.0
  Se  Se3  1  0.500  0.500  0.000  1.0
[/CIF]
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The crystal structure described by NaAsSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. Na(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form NaSe6 octahedra that share corners with six 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 octahedra are not tilted. As(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form AsSe6 octahedra that share corners with six 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 octahedra are not tilted. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Na(1) and four equivalent As(1) atoms to form SeNa2As4 octahedra that share corners with six equivalent Se(1)Na2As4 octahedra, edges with four equivalent Se(1)Na2As4 octahedra, and edges with eight equivalent Se(2)Na4As2 octahedra. The corner-sharing octahedra are not tilted. In the second Se site, Se(2) is bonded to four equivalent Na(1) and two equivalent As(1) atoms to form SeNa4As2 octahedra that share corners with six equivalent Se(2)Na4As2 octahedra, edges with four equivalent Se(2)Na4As2 octahedra, and edges with eight equivalent Se(1)Na2As4 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaAsSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.001
_cell_length_b   4.001
_cell_length_c   5.568
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   89.141
_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
  As  As1  1  0.500  0.500  0.500  1.0
  Se  Se2  1  0.000  0.000  0.500  1.0
  Se  Se3  1  0.500  0.500  0.000  1.0
[/CIF]
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