The crystal structure described by As2Se crystallizes in the tetragonal I4_1/amd space group. As(1) is bonded in a distorted linear geometry to four equivalent As(1) and two equivalent Se(1) atoms. Se(1) is bonded in a 4-coordinate geometry to four equivalent As(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_As2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.653
_cell_length_b   5.653
_cell_length_c   5.653
_cell_angle_alpha   102.730
_cell_angle_beta   102.730
_cell_angle_gamma   124.007
_symmetry_Int_Tables_number   1
_cell_volume   132.220
_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
  As  As0  1  0.125  0.875  0.250  1.0
  As  As1  1  0.625  0.875  0.750  1.0
  As  As2  1  0.125  0.375  0.250  1.0
  As  As3  1  0.125  0.875  0.750  1.0
  Se  Se4  1  0.750  0.250  0.500  1.0
  Se  Se5  1  0.500  0.500  0.000  1.0
[/CIF]
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The crystal structure described by As2Se crystallizes in the tetragonal I4_1/amd space group. As(1) is bonded in a distorted linear geometry to four equivalent As(1) and two equivalent Se(1) atoms. Se(1) is bonded in a 4-coordinate geometry to four equivalent As(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_As2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.653
_cell_length_b   5.653
_cell_length_c   5.653
_cell_angle_alpha   102.730
_cell_angle_beta   102.730
_cell_angle_gamma   124.007
_symmetry_Int_Tables_number   1
_cell_volume   132.220
_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
  As  As0  1  0.125  0.875  0.250  1.0
  As  As1  1  0.625  0.875  0.750  1.0
  As  As2  1  0.125  0.375  0.250  1.0
  As  As3  1  0.125  0.875  0.750  1.0
  Se  Se4  1  0.750  0.250  0.500  1.0
  Se  Se5  1  0.500  0.500  0.000  1.0
[/CIF]
.