The material structure described by GdCu5Se4 crystallizes in the monoclinic C2/m space group. Gd(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form GdSe6 octahedra that share corners with two equivalent Cu(2)Se4 tetrahedra, corners with ten equivalent Cu(3)Se4 tetrahedra, edges with two equivalent Gd(1)Se6 octahedra, edges with four equivalent Cu(1)Se6 octahedra, edges with two equivalent Cu(3)Se4 tetrahedra, and edges with four equivalent Cu(2)Se4 tetrahedra. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CuSe6 octahedra that share corners with two equivalent Cu(3)Se4 tetrahedra, corners with ten equivalent Cu(2)Se4 tetrahedra, edges with two equivalent Cu(1)Se6 octahedra, edges with four equivalent Gd(1)Se6 octahedra, edges with two equivalent Cu(2)Se4 tetrahedra, and edges with four equivalent Cu(3)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(1) and three equivalent Se(2) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Gd(1)Se6 octahedra, corners with five equivalent Cu(1)Se6 octahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with four equivalent Cu(3)Se4 tetrahedra,  an edgeedge with one Cu(1)Se6 octahedra, edges with two equivalent Gd(1)Se6 octahedra,  an edgeedge with one Cu(3)Se4 tetrahedra, and edges with two equivalent Cu(2)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 13-57°. In the third Cu site, Cu(3) is bonded to one Se(2) and three equivalent Se(1) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(1)Se6 octahedra, corners with five equivalent Gd(1)Se6 octahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra,  an edgeedge with one Gd(1)Se6 octahedra, edges with two equivalent Cu(1)Se6 octahedra,  an edgeedge with one Cu(2)Se4 tetrahedra, and edges with two equivalent Cu(3)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 11-56°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Gd(1), one Cu(1), one Cu(2), and three equivalent Cu(3) atoms to form distorted SeGd2Cu5 pentagonal bipyramids that share corners with three equivalent Se(1)Gd2Cu5 pentagonal bipyramids, edges with five equivalent Se(1)Gd2Cu5 pentagonal bipyramids, and edges with seven equivalent Se(2)GdCu6 pentagonal bipyramids. In the second Se site, Se(2) is bonded to one Gd(1), one Cu(3), two equivalent Cu(1), and three equivalent Cu(2) atoms to form distorted SeGdCu6 pentagonal bipyramids that share corners with three equivalent Se(2)GdCu6 pentagonal bipyramids, edges with five equivalent Se(2)GdCu6 pentagonal bipyramids, and edges with seven equivalent Se(1)Gd2Cu5 pentagonal bipyramids. is represented by the CIF card [CIF]
data_GdCu5Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.698
_cell_length_b   7.698
_cell_length_c   6.917
_cell_angle_alpha   64.418
_cell_angle_beta   64.418
_cell_angle_gamma   30.510
_symmetry_Int_Tables_number   1
_cell_volume   186.071
_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
  Gd  Gd0  1  0.500  0.500  0.500  1.0
  Cu  Cu1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.810  0.810  0.857  1.0
  Cu  Cu3  1  0.311  0.311  0.356  1.0
  Cu  Cu4  1  0.190  0.190  0.143  1.0
  Cu  Cu5  1  0.689  0.689  0.644  1.0
  Se  Se6  1  0.125  0.125  0.551  1.0
  Se  Se7  1  0.619  0.619  0.038  1.0
  Se  Se8  1  0.875  0.875  0.449  1.0
  Se  Se9  1  0.381  0.381  0.962  1.0
[/CIF]
.
The material structure described by GdCu5Se4 crystallizes in the monoclinic C2/m space group. Gd(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form GdSe6 octahedra that share corners with two equivalent Cu(2)Se4 tetrahedra, corners with ten equivalent Cu(3)Se4 tetrahedra, edges with two equivalent Gd(1)Se6 octahedra, edges with four equivalent Cu(1)Se6 octahedra, edges with two equivalent Cu(3)Se4 tetrahedra, and edges with four equivalent Cu(2)Se4 tetrahedra. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CuSe6 octahedra that share corners with two equivalent Cu(3)Se4 tetrahedra, corners with ten equivalent Cu(2)Se4 tetrahedra, edges with two equivalent Cu(1)Se6 octahedra, edges with four equivalent Gd(1)Se6 octahedra, edges with two equivalent Cu(2)Se4 tetrahedra, and edges with four equivalent Cu(3)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(1) and three equivalent Se(2) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Gd(1)Se6 octahedra, corners with five equivalent Cu(1)Se6 octahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with four equivalent Cu(3)Se4 tetrahedra,  an edgeedge with one Cu(1)Se6 octahedra, edges with two equivalent Gd(1)Se6 octahedra,  an edgeedge with one Cu(3)Se4 tetrahedra, and edges with two equivalent Cu(2)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 13-57°. In the third Cu site, Cu(3) is bonded to one Se(2) and three equivalent Se(1) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Cu(1)Se6 octahedra, corners with five equivalent Gd(1)Se6 octahedra, corners with two equivalent Cu(3)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra,  an edgeedge with one Gd(1)Se6 octahedra, edges with two equivalent Cu(1)Se6 octahedra,  an edgeedge with one Cu(2)Se4 tetrahedra, and edges with two equivalent Cu(3)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 11-56°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Gd(1), one Cu(1), one Cu(2), and three equivalent Cu(3) atoms to form distorted SeGd2Cu5 pentagonal bipyramids that share corners with three equivalent Se(1)Gd2Cu5 pentagonal bipyramids, edges with five equivalent Se(1)Gd2Cu5 pentagonal bipyramids, and edges with seven equivalent Se(2)GdCu6 pentagonal bipyramids. In the second Se site, Se(2) is bonded to one Gd(1), one Cu(3), two equivalent Cu(1), and three equivalent Cu(2) atoms to form distorted SeGdCu6 pentagonal bipyramids that share corners with three equivalent Se(2)GdCu6 pentagonal bipyramids, edges with five equivalent Se(2)GdCu6 pentagonal bipyramids, and edges with seven equivalent Se(1)Gd2Cu5 pentagonal bipyramids. is represented by the CIF card [CIF]
data_GdCu5Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.698
_cell_length_b   7.698
_cell_length_c   6.917
_cell_angle_alpha   64.418
_cell_angle_beta   64.418
_cell_angle_gamma   30.510
_symmetry_Int_Tables_number   1
_cell_volume   186.071
_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
  Gd  Gd0  1  0.500  0.500  0.500  1.0
  Cu  Cu1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.810  0.810  0.857  1.0
  Cu  Cu3  1  0.311  0.311  0.356  1.0
  Cu  Cu4  1  0.190  0.190  0.143  1.0
  Cu  Cu5  1  0.689  0.689  0.644  1.0
  Se  Se6  1  0.125  0.125  0.551  1.0
  Se  Se7  1  0.619  0.619  0.038  1.0
  Se  Se8  1  0.875  0.875  0.449  1.0
  Se  Se9  1  0.381  0.381  0.962  1.0
[/CIF]
.