The compound described by GdCuSe2 crystallizes in the monoclinic P2_1/c space group. Gd(1) is bonded in a 7-coordinate geometry to three equivalent Se(1) and four equivalent Se(2) atoms. Cu(1) is bonded to one Se(2) and three equivalent Se(1) 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 in a 6-coordinate geometry to three equivalent Gd(1) and three equivalent Cu(1) atoms. In the second Se site, Se(2) is bonded to four equivalent Gd(1) and one Cu(1) atom to form a mixture of distorted corner and edge-sharing SeGd4Cu trigonal bipyramids. is represented by the CIF file [CIF]
data_GdCuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.628
_cell_length_b   7.099
_cell_length_c   7.347
_cell_angle_alpha   89.999
_cell_angle_beta   90.000
_cell_angle_gamma   96.398
_symmetry_Int_Tables_number   1
_cell_volume   343.520
_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
  Gd  Gd0  1  0.193  0.800  0.954  1.0
  Gd  Gd1  1  0.807  0.700  0.454  1.0
  Gd  Gd2  1  0.807  0.200  0.046  1.0
  Gd  Gd3  1  0.193  0.300  0.546  1.0
  Cu  Cu4  1  0.569  0.545  0.841  1.0
  Cu  Cu5  1  0.431  0.955  0.341  1.0
  Cu  Cu6  1  0.431  0.455  0.159  1.0
  Cu  Cu7  1  0.569  0.045  0.659  1.0
  Se  Se8  1  0.598  0.280  0.388  1.0
  Se  Se9  1  0.402  0.220  0.888  1.0
  Se  Se10  1  0.402  0.720  0.612  1.0
  Se  Se11  1  0.598  0.780  0.112  1.0
  Se  Se12  1  0.922  0.503  0.775  1.0
  Se  Se13  1  0.078  0.997  0.275  1.0
  Se  Se14  1  0.078  0.497  0.225  1.0
  Se  Se15  1  0.922  0.003  0.725  1.0
[/CIF]
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The compound described by GdCuSe2 crystallizes in the monoclinic P2_1/c space group. Gd(1) is bonded in a 7-coordinate geometry to three equivalent Se(1) and four equivalent Se(2) atoms. Cu(1) is bonded to one Se(2) and three equivalent Se(1) 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 in a 6-coordinate geometry to three equivalent Gd(1) and three equivalent Cu(1) atoms. In the second Se site, Se(2) is bonded to four equivalent Gd(1) and one Cu(1) atom to form a mixture of distorted corner and edge-sharing SeGd4Cu trigonal bipyramids. is represented by the CIF file [CIF]
data_GdCuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.628
_cell_length_b   7.099
_cell_length_c   7.347
_cell_angle_alpha   89.999
_cell_angle_beta   90.000
_cell_angle_gamma   96.398
_symmetry_Int_Tables_number   1
_cell_volume   343.520
_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
  Gd  Gd0  1  0.193  0.800  0.954  1.0
  Gd  Gd1  1  0.807  0.700  0.454  1.0
  Gd  Gd2  1  0.807  0.200  0.046  1.0
  Gd  Gd3  1  0.193  0.300  0.546  1.0
  Cu  Cu4  1  0.569  0.545  0.841  1.0
  Cu  Cu5  1  0.431  0.955  0.341  1.0
  Cu  Cu6  1  0.431  0.455  0.159  1.0
  Cu  Cu7  1  0.569  0.045  0.659  1.0
  Se  Se8  1  0.598  0.280  0.388  1.0
  Se  Se9  1  0.402  0.220  0.888  1.0
  Se  Se10  1  0.402  0.720  0.612  1.0
  Se  Se11  1  0.598  0.780  0.112  1.0
  Se  Se12  1  0.922  0.503  0.775  1.0
  Se  Se13  1  0.078  0.997  0.275  1.0
  Se  Se14  1  0.078  0.497  0.225  1.0
  Se  Se15  1  0.922  0.003  0.725  1.0
[/CIF]
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