The crystal structure described by Nb5Cu4Si4 crystallizes in the tetragonal I4/m space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a square co-planar geometry to four equivalent Si(1) atoms. In the second Nb site, Nb(2) is bonded in a 5-coordinate geometry to four equivalent Cu(1) and five equivalent Si(1) atoms. Cu(1) is bonded to four equivalent Nb(2), five equivalent Cu(1), and three equivalent Si(1) atoms to form a mixture of face, corner, and edge-sharing CuNb4Cu5Si3 cuboctahedra. Si(1) is bonded in a 9-coordinate geometry to one Nb(1), five equivalent Nb(2), and three equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_Nb5(CuSi)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.598
_cell_length_b   7.433
_cell_length_c   7.433
_cell_angle_alpha   86.642
_cell_angle_beta   75.993
_cell_angle_gamma   75.993
_symmetry_Int_Tables_number   1
_cell_volume   187.143
_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
  Nb  Nb0  1  0.500  0.000  0.000  1.0
  Nb  Nb1  1  0.804  0.066  0.326  1.0
  Nb  Nb2  1  0.130  0.674  0.066  1.0
  Nb  Nb3  1  0.870  0.326  0.934  1.0
  Nb  Nb4  1  0.196  0.934  0.674  1.0
  Cu  Cu5  1  0.919  0.684  0.477  1.0
  Cu  Cu6  1  0.081  0.316  0.523  1.0
  Cu  Cu7  1  0.604  0.477  0.316  1.0
  Cu  Cu8  1  0.396  0.523  0.684  1.0
  Si  Si9  1  0.558  0.196  0.688  1.0
  Si  Si10  1  0.246  0.312  0.196  1.0
  Si  Si11  1  0.754  0.688  0.804  1.0
  Si  Si12  1  0.442  0.804  0.312  1.0
[/CIF]
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The crystal structure described by Nb5Cu4Si4 crystallizes in the tetragonal I4/m space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a square co-planar geometry to four equivalent Si(1) atoms. In the second Nb site, Nb(2) is bonded in a 5-coordinate geometry to four equivalent Cu(1) and five equivalent Si(1) atoms. Cu(1) is bonded to four equivalent Nb(2), five equivalent Cu(1), and three equivalent Si(1) atoms to form a mixture of face, corner, and edge-sharing CuNb4Cu5Si3 cuboctahedra. Si(1) is bonded in a 9-coordinate geometry to one Nb(1), five equivalent Nb(2), and three equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_Nb5(CuSi)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.598
_cell_length_b   7.433
_cell_length_c   7.433
_cell_angle_alpha   86.642
_cell_angle_beta   75.993
_cell_angle_gamma   75.993
_symmetry_Int_Tables_number   1
_cell_volume   187.143
_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
  Nb  Nb0  1  0.500  0.000  0.000  1.0
  Nb  Nb1  1  0.804  0.066  0.326  1.0
  Nb  Nb2  1  0.130  0.674  0.066  1.0
  Nb  Nb3  1  0.870  0.326  0.934  1.0
  Nb  Nb4  1  0.196  0.934  0.674  1.0
  Cu  Cu5  1  0.919  0.684  0.477  1.0
  Cu  Cu6  1  0.081  0.316  0.523  1.0
  Cu  Cu7  1  0.604  0.477  0.316  1.0
  Cu  Cu8  1  0.396  0.523  0.684  1.0
  Si  Si9  1  0.558  0.196  0.688  1.0
  Si  Si10  1  0.246  0.312  0.196  1.0
  Si  Si11  1  0.754  0.688  0.804  1.0
  Si  Si12  1  0.442  0.804  0.312  1.0
[/CIF]
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