The crystal structure described by K2NbCuSe2 crystallizes in the orthorhombic Fddd space group. K(1) is bonded in a 5-coordinate geometry to one Cu(1) and four equivalent Se(1) atoms. Nb(1) is bonded in a distorted linear geometry to four equivalent Cu(1) and two equivalent Se(1) atoms. Cu(1) is bonded in a 6-coordinate geometry to two equivalent K(1) and four equivalent Nb(1) atoms. Se(1) is bonded in a 5-coordinate geometry to four equivalent K(1) and one Nb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2NbCuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.896
_cell_length_b   6.915
_cell_length_c   18.155
_cell_angle_alpha   86.031
_cell_angle_beta   80.655
_cell_angle_gamma   64.767
_symmetry_Int_Tables_number   1
_cell_volume   660.744
_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
  K  K0  1  0.557  0.254  0.573  1.0
  K  K1  1  0.870  0.746  0.573  1.0
  K  K2  1  0.189  0.254  0.427  1.0
  K  K3  1  0.193  0.246  0.927  1.0
  K  K4  1  0.384  0.746  0.427  1.0
  K  K5  1  0.880  0.754  0.927  1.0
  K  K6  1  0.561  0.246  0.073  1.0
  K  K7  1  0.366  0.754  0.073  1.0
  Nb  Nb8  1  0.875  0.250  0.250  1.0
  Nb  Nb9  1  0.875  0.750  0.250  1.0
  Nb  Nb10  1  0.875  0.250  0.750  1.0
  Nb  Nb11  1  0.375  0.750  0.750  1.0
  Cu  Cu12  1  0.375  0.250  0.250  1.0
  Cu  Cu13  1  0.375  0.750  0.250  1.0
  Cu  Cu14  1  0.375  0.250  0.750  1.0
  Cu  Cu15  1  0.875  0.750  0.750  1.0
  Se  Se16  1  0.044  0.229  0.116  1.0
  Se  Se17  1  0.839  0.771  0.116  1.0
  Se  Se18  1  0.727  0.229  0.884  1.0
  Se  Se19  1  0.706  0.271  0.384  1.0
  Se  Se20  1  0.389  0.771  0.884  1.0
  Se  Se21  1  0.911  0.729  0.384  1.0
  Se  Se22  1  0.023  0.271  0.616  1.0
  Se  Se23  1  0.361  0.729  0.616  1.0
[/CIF]
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The crystal structure described by K2NbCuSe2 crystallizes in the orthorhombic Fddd space group. K(1) is bonded in a 5-coordinate geometry to one Cu(1) and four equivalent Se(1) atoms. Nb(1) is bonded in a distorted linear geometry to four equivalent Cu(1) and two equivalent Se(1) atoms. Cu(1) is bonded in a 6-coordinate geometry to two equivalent K(1) and four equivalent Nb(1) atoms. Se(1) is bonded in a 5-coordinate geometry to four equivalent K(1) and one Nb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2NbCuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.896
_cell_length_b   6.915
_cell_length_c   18.155
_cell_angle_alpha   86.031
_cell_angle_beta   80.655
_cell_angle_gamma   64.767
_symmetry_Int_Tables_number   1
_cell_volume   660.744
_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
  K  K0  1  0.557  0.254  0.573  1.0
  K  K1  1  0.870  0.746  0.573  1.0
  K  K2  1  0.189  0.254  0.427  1.0
  K  K3  1  0.193  0.246  0.927  1.0
  K  K4  1  0.384  0.746  0.427  1.0
  K  K5  1  0.880  0.754  0.927  1.0
  K  K6  1  0.561  0.246  0.073  1.0
  K  K7  1  0.366  0.754  0.073  1.0
  Nb  Nb8  1  0.875  0.250  0.250  1.0
  Nb  Nb9  1  0.875  0.750  0.250  1.0
  Nb  Nb10  1  0.875  0.250  0.750  1.0
  Nb  Nb11  1  0.375  0.750  0.750  1.0
  Cu  Cu12  1  0.375  0.250  0.250  1.0
  Cu  Cu13  1  0.375  0.750  0.250  1.0
  Cu  Cu14  1  0.375  0.250  0.750  1.0
  Cu  Cu15  1  0.875  0.750  0.750  1.0
  Se  Se16  1  0.044  0.229  0.116  1.0
  Se  Se17  1  0.839  0.771  0.116  1.0
  Se  Se18  1  0.727  0.229  0.884  1.0
  Se  Se19  1  0.706  0.271  0.384  1.0
  Se  Se20  1  0.389  0.771  0.884  1.0
  Se  Se21  1  0.911  0.729  0.384  1.0
  Se  Se22  1  0.023  0.271  0.616  1.0
  Se  Se23  1  0.361  0.729  0.616  1.0
[/CIF]
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