The material described by Nb3Si crystallizes in the tetragonal I-4 space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 2-coordinate geometry to two equivalent Si(1) atoms. In the second Nb site, Nb(3) is bonded in a 3-coordinate geometry to three equivalent Si(1) atoms. In the third Nb site, Nb(2) is bonded in a 4-coordinate geometry to four equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Nb(1), three equivalent Nb(3), and four equivalent Nb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb3Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.166
_cell_length_b   7.763
_cell_length_c   7.763
_cell_angle_alpha   83.643
_cell_angle_beta   70.565
_cell_angle_gamma   70.565
_symmetry_Int_Tables_number   1
_cell_volume   276.863
_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
  Nb  Nb0  1  0.661  0.181  0.018  1.0
  Nb  Nb1  1  0.860  0.819  0.982  1.0
  Nb  Nb2  1  0.158  0.982  0.181  1.0
  Nb  Nb3  1  0.321  0.018  0.819  1.0
  Nb  Nb4  1  0.997  0.376  0.661  1.0
  Nb  Nb5  1  0.033  0.624  0.339  1.0
  Nb  Nb6  1  0.628  0.339  0.376  1.0
  Nb  Nb7  1  0.343  0.661  0.624  1.0
  Nb  Nb8  1  0.031  0.405  0.029  1.0
  Nb  Nb9  1  0.465  0.595  0.971  1.0
  Nb  Nb10  1  0.564  0.971  0.405  1.0
  Nb  Nb11  1  0.940  0.029  0.595  1.0
  Si  Si12  1  0.488  0.324  0.739  1.0
  Si  Si13  1  0.551  0.676  0.261  1.0
  Si  Si14  1  0.188  0.261  0.324  1.0
  Si  Si15  1  0.773  0.739  0.676  1.0
[/CIF]
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The material described by Nb3Si crystallizes in the tetragonal I-4 space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 2-coordinate geometry to two equivalent Si(1) atoms. In the second Nb site, Nb(3) is bonded in a 3-coordinate geometry to three equivalent Si(1) atoms. In the third Nb site, Nb(2) is bonded in a 4-coordinate geometry to four equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Nb(1), three equivalent Nb(3), and four equivalent Nb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb3Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.166
_cell_length_b   7.763
_cell_length_c   7.763
_cell_angle_alpha   83.643
_cell_angle_beta   70.565
_cell_angle_gamma   70.565
_symmetry_Int_Tables_number   1
_cell_volume   276.863
_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
  Nb  Nb0  1  0.661  0.181  0.018  1.0
  Nb  Nb1  1  0.860  0.819  0.982  1.0
  Nb  Nb2  1  0.158  0.982  0.181  1.0
  Nb  Nb3  1  0.321  0.018  0.819  1.0
  Nb  Nb4  1  0.997  0.376  0.661  1.0
  Nb  Nb5  1  0.033  0.624  0.339  1.0
  Nb  Nb6  1  0.628  0.339  0.376  1.0
  Nb  Nb7  1  0.343  0.661  0.624  1.0
  Nb  Nb8  1  0.031  0.405  0.029  1.0
  Nb  Nb9  1  0.465  0.595  0.971  1.0
  Nb  Nb10  1  0.564  0.971  0.405  1.0
  Nb  Nb11  1  0.940  0.029  0.595  1.0
  Si  Si12  1  0.488  0.324  0.739  1.0
  Si  Si13  1  0.551  0.676  0.261  1.0
  Si  Si14  1  0.188  0.261  0.324  1.0
  Si  Si15  1  0.773  0.739  0.676  1.0
[/CIF]
.