The compound described by CuAsSe crystallizes in the orthorhombic Pnma space group. Cu(1) is bonded to one As(1) and three equivalent Se(1) atoms to form CuAsSe3 tetrahedra that share  a cornercorner with one Se(1)Cu3As tetrahedra and corners with six equivalent Cu(1)AsSe3 tetrahedra. As(1) is bonded in a 4-coordinate geometry to one Cu(1), two equivalent As(1), and one Se(1) atom. Se(1) is bonded to three equivalent Cu(1) and one As(1) atom to form SeCu3As tetrahedra that share  a cornercorner with one Cu(1)AsSe3 tetrahedra and corners with six equivalent Se(1)Cu3As tetrahedra. is represented by the CIF file [CIF]
data_CuAsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.934
_cell_length_b   5.567
_cell_length_c   11.742
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   257.169
_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
  Cu  Cu0  1  0.250  0.088  0.832  1.0
  Cu  Cu1  1  0.750  0.912  0.168  1.0
  Cu  Cu2  1  0.750  0.588  0.668  1.0
  Cu  Cu3  1  0.250  0.412  0.332  1.0
  As  As4  1  0.250  0.360  0.985  1.0
  As  As5  1  0.750  0.640  0.015  1.0
  As  As6  1  0.750  0.860  0.515  1.0
  As  As7  1  0.250  0.140  0.485  1.0
  Se  Se8  1  0.250  0.342  0.667  1.0
  Se  Se9  1  0.750  0.658  0.333  1.0
  Se  Se10  1  0.750  0.842  0.833  1.0
  Se  Se11  1  0.250  0.158  0.167  1.0
[/CIF]
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The compound described by CuAsSe crystallizes in the orthorhombic Pnma space group. Cu(1) is bonded to one As(1) and three equivalent Se(1) atoms to form CuAsSe3 tetrahedra that share  a cornercorner with one Se(1)Cu3As tetrahedra and corners with six equivalent Cu(1)AsSe3 tetrahedra. As(1) is bonded in a 4-coordinate geometry to one Cu(1), two equivalent As(1), and one Se(1) atom. Se(1) is bonded to three equivalent Cu(1) and one As(1) atom to form SeCu3As tetrahedra that share  a cornercorner with one Cu(1)AsSe3 tetrahedra and corners with six equivalent Se(1)Cu3As tetrahedra. is represented by the CIF file [CIF]
data_CuAsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.934
_cell_length_b   5.567
_cell_length_c   11.742
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   257.169
_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
  Cu  Cu0  1  0.250  0.088  0.832  1.0
  Cu  Cu1  1  0.750  0.912  0.168  1.0
  Cu  Cu2  1  0.750  0.588  0.668  1.0
  Cu  Cu3  1  0.250  0.412  0.332  1.0
  As  As4  1  0.250  0.360  0.985  1.0
  As  As5  1  0.750  0.640  0.015  1.0
  As  As6  1  0.750  0.860  0.515  1.0
  As  As7  1  0.250  0.140  0.485  1.0
  Se  Se8  1  0.250  0.342  0.667  1.0
  Se  Se9  1  0.750  0.658  0.333  1.0
  Se  Se10  1  0.750  0.842  0.833  1.0
  Se  Se11  1  0.250  0.158  0.167  1.0
[/CIF]
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