The compound described by LaCuSe2 crystallizes in the monoclinic P2_1/c space group. La(1) is bonded in a 7-coordinate geometry to three equivalent Se(2) and four equivalent Se(1) atoms. Cu(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form a mixture of distorted corner and edge-sharing CuSe4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to four equivalent La(1) and one Cu(1) atom to form a mixture of distorted corner and edge-sharing SeLa4Cu trigonal bipyramids. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to three equivalent La(1) and three equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_LaCuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.841
_cell_length_b   7.249
_cell_length_c   7.589
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   97.271
_symmetry_Int_Tables_number   1
_cell_volume   373.312
_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
  La  La0  1  0.691  0.300  0.550  1.0
  La  La1  1  0.309  0.200  0.050  1.0
  La  La2  1  0.309  0.700  0.450  1.0
  La  La3  1  0.691  0.800  0.950  1.0
  Cu  Cu4  1  0.067  0.546  0.841  1.0
  Cu  Cu5  1  0.933  0.454  0.159  1.0
  Cu  Cu6  1  0.067  0.046  0.659  1.0
  Cu  Cu7  1  0.933  0.954  0.341  1.0
  Se  Se8  1  0.410  0.001  0.725  1.0
  Se  Se9  1  0.410  0.501  0.775  1.0
  Se  Se10  1  0.590  0.499  0.225  1.0
  Se  Se11  1  0.590  0.999  0.275  1.0
  Se  Se12  1  0.909  0.722  0.615  1.0
  Se  Se13  1  0.091  0.778  0.115  1.0
  Se  Se14  1  0.091  0.278  0.385  1.0
  Se  Se15  1  0.909  0.222  0.885  1.0
[/CIF]
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The compound described by LaCuSe2 crystallizes in the monoclinic P2_1/c space group. La(1) is bonded in a 7-coordinate geometry to three equivalent Se(2) and four equivalent Se(1) atoms. Cu(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form a mixture of distorted corner and edge-sharing CuSe4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to four equivalent La(1) and one Cu(1) atom to form a mixture of distorted corner and edge-sharing SeLa4Cu trigonal bipyramids. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to three equivalent La(1) and three equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_LaCuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.841
_cell_length_b   7.249
_cell_length_c   7.589
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   97.271
_symmetry_Int_Tables_number   1
_cell_volume   373.312
_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
  La  La0  1  0.691  0.300  0.550  1.0
  La  La1  1  0.309  0.200  0.050  1.0
  La  La2  1  0.309  0.700  0.450  1.0
  La  La3  1  0.691  0.800  0.950  1.0
  Cu  Cu4  1  0.067  0.546  0.841  1.0
  Cu  Cu5  1  0.933  0.454  0.159  1.0
  Cu  Cu6  1  0.067  0.046  0.659  1.0
  Cu  Cu7  1  0.933  0.954  0.341  1.0
  Se  Se8  1  0.410  0.001  0.725  1.0
  Se  Se9  1  0.410  0.501  0.775  1.0
  Se  Se10  1  0.590  0.499  0.225  1.0
  Se  Se11  1  0.590  0.999  0.275  1.0
  Se  Se12  1  0.909  0.722  0.615  1.0
  Se  Se13  1  0.091  0.778  0.115  1.0
  Se  Se14  1  0.091  0.278  0.385  1.0
  Se  Se15  1  0.909  0.222  0.885  1.0
[/CIF]
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