The material structure described by KGd2CuSe4 crystallizes in the orthorhombic Cmcm space group. K(1) is bonded in a 6-coordinate geometry to two equivalent Se(3) and four equivalent Se(2) atoms. Gd(1) is bonded to one Se(3), two equivalent Se(1), and three equivalent Se(2) atoms to form GdSe6 octahedra that share corners with three equivalent Gd(1)Se6 octahedra,  a cornercorner with one Cu(1)Se4 tetrahedra, edges with five equivalent Gd(1)Se6 octahedra, and edges with two equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 0-41°. Cu(1) is bonded to two equivalent Se(2) and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Gd(1)Se6 octahedra, corners with two equivalent Cu(1)Se4 tetrahedra, and edges with four equivalent Gd(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a square co-planar geometry to four equivalent Gd(1) atoms. In the second Se site, Se(2) is bonded to two equivalent K(1), three equivalent Gd(1), and one Cu(1) atom to form a mixture of distorted face, corner, and edge-sharing SeK2Gd3Cu octahedra. The corner-sharing octahedral tilt angles are 63°. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent Gd(1), and two equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_KGd2CuSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.406
_cell_length_b   7.406
_cell_length_c   14.506
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   147.327
_symmetry_Int_Tables_number   1
_cell_volume   429.475
_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
  K  K0  1  0.111  0.889  0.250  1.0
  K  K1  1  0.889  0.111  0.750  1.0
  Gd  Gd2  1  0.365  0.635  0.064  1.0
  Gd  Gd3  1  0.365  0.635  0.436  1.0
  Gd  Gd4  1  0.635  0.365  0.564  1.0
  Gd  Gd5  1  0.635  0.365  0.936  1.0
  Cu  Cu6  1  0.840  0.160  0.250  1.0
  Cu  Cu7  1  0.160  0.840  0.750  1.0
  Se  Se8  1  0.000  0.000  0.000  1.0
  Se  Se9  1  0.734  0.266  0.113  1.0
  Se  Se10  1  0.435  0.565  0.250  1.0
  Se  Se11  1  0.734  0.266  0.387  1.0
  Se  Se12  1  0.000  0.000  0.500  1.0
  Se  Se13  1  0.266  0.734  0.613  1.0
  Se  Se14  1  0.565  0.435  0.750  1.0
  Se  Se15  1  0.266  0.734  0.887  1.0
[/CIF]
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The material structure described by KGd2CuSe4 crystallizes in the orthorhombic Cmcm space group. K(1) is bonded in a 6-coordinate geometry to two equivalent Se(3) and four equivalent Se(2) atoms. Gd(1) is bonded to one Se(3), two equivalent Se(1), and three equivalent Se(2) atoms to form GdSe6 octahedra that share corners with three equivalent Gd(1)Se6 octahedra,  a cornercorner with one Cu(1)Se4 tetrahedra, edges with five equivalent Gd(1)Se6 octahedra, and edges with two equivalent Cu(1)Se4 tetrahedra. The corner-sharing octahedral tilt angles range from 0-41°. Cu(1) is bonded to two equivalent Se(2) and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Gd(1)Se6 octahedra, corners with two equivalent Cu(1)Se4 tetrahedra, and edges with four equivalent Gd(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a square co-planar geometry to four equivalent Gd(1) atoms. In the second Se site, Se(2) is bonded to two equivalent K(1), three equivalent Gd(1), and one Cu(1) atom to form a mixture of distorted face, corner, and edge-sharing SeK2Gd3Cu octahedra. The corner-sharing octahedral tilt angles are 63°. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent Gd(1), and two equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_KGd2CuSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.406
_cell_length_b   7.406
_cell_length_c   14.506
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   147.327
_symmetry_Int_Tables_number   1
_cell_volume   429.475
_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
  K  K0  1  0.111  0.889  0.250  1.0
  K  K1  1  0.889  0.111  0.750  1.0
  Gd  Gd2  1  0.365  0.635  0.064  1.0
  Gd  Gd3  1  0.365  0.635  0.436  1.0
  Gd  Gd4  1  0.635  0.365  0.564  1.0
  Gd  Gd5  1  0.635  0.365  0.936  1.0
  Cu  Cu6  1  0.840  0.160  0.250  1.0
  Cu  Cu7  1  0.160  0.840  0.750  1.0
  Se  Se8  1  0.000  0.000  0.000  1.0
  Se  Se9  1  0.734  0.266  0.113  1.0
  Se  Se10  1  0.435  0.565  0.250  1.0
  Se  Se11  1  0.734  0.266  0.387  1.0
  Se  Se12  1  0.000  0.000  0.500  1.0
  Se  Se13  1  0.266  0.734  0.613  1.0
  Se  Se14  1  0.565  0.435  0.750  1.0
  Se  Se15  1  0.266  0.734  0.887  1.0
[/CIF]
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