data_NbCuSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.78
_cell_length_b   2.78
_cell_length_c   7.82
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   102.77
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbCuSi2
_chemical_formula_sum   'Nb1 Cu1 Si2'
_cell_volume   59.12
_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  Nb1  1  0.0  0.0  0.91  1.0
  Cu  Cu0  1  0.0  0.0  0.0  1.0
  Si  Si2  1  0.74  0.0  0.94  1.0
  Si  Si3  1  0.74  0.0  0.87  1.0

data_NbCuSi2
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.78
_cell_length_b   2.78
_cell_length_c   7.82
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   102.77
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbCuSi2
_chemical_formula_sum   'Nb1 Cu1 Si2'
_cell_volume   59.12
_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  0.0  0.0  0.91  1.0
  Cu  Cu1  1  0.0  0.0  0.0  1.0
  Si  Si2  1  0.74  0.0  0.87  1.0
  Si  Si3  1  0.74  0.0  0.94  1.0

Nb Cu Si Si
NbCuSi2 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one NbCuSi2 cluster. Nb(1) is bonded in a 2-coordinate geometry to one Cu(1) and one Si(1) atom. The Nb(1)-Cu(1) bond length is 0.71 Å. The Nb(1)-Si(1) bond length is 0.78 Å. Cu(1) is bonded in a single-bond geometry to one Nb(1) atom. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 2-coordinate geometry to one Nb(1) and one Si(2) atom. The Si(1)-Si(2) bond length is 0.53 Å. In the second Si site, Si(2) is bonded in a distorted single-bond geometry to one Si(1) atom.