data_Nb4Ir
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.71
_cell_length_b   7.71
_cell_length_c   7.71
_cell_angle_alpha   153.02
_cell_angle_beta   153.02
_cell_angle_gamma   38.53
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Nb4Ir
_chemical_formula_sum   'Nb4 Ir1'
_cell_volume   94.28
_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  0.8  0.0  0.64  1.0
  Nb  Nb2  1  0.0  0.0  0.03  1.0
  Nb  Nb3  1  0.0  0.0  0.53  1.0
  Nb  Nb4  1  0.0  0.8  0.64  1.0
  Ir  Ir0  1  0.0  0.0  0.0  1.0

data_Nb4Ir
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.09
_cell_length_b   5.09
_cell_length_c   7.71
_cell_angle_alpha   90.0
_cell_angle_beta   109.26
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Nb4Ir
_chemical_formula_sum   'Nb8 Ir2'
_cell_volume   188.56
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  4  0.4  0.4  0.16  1.0
  Nb  Nb1  2  0.0  0.0  0.47  1.0
  Nb  Nb2  2  0.0  0.0  0.97  1.0
  Ir  Ir3  2  0.0  0.0  0.0  1.0

Nb Nb Nb Nb Ir
Nb4Ir crystallizes in the monoclinic Cm space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(3), and one Ir(1) atom. The Nb(1)-Nb(1) bond length is 1.02 Å. The Nb(1)-Nb(3) bond length is 2.34 Å. The Nb(1)-Ir(1) bond length is 1.56 Å. In the second Nb site, Nb(2) is bonded in a single-bond geometry to one Nb(3) and one Ir(1) atom. The Nb(2)-Nb(3) bond length is 3.85 Å. The Nb(2)-Ir(1) bond length is 0.24 Å. In the third Nb site, Nb(3) is bonded in a 7-coordinate geometry to one Nb(2), two equivalent Nb(1), and four equivalent Nb(3) atoms. All Nb(3)-Nb(3) bond lengths are 3.60 Å. Ir(1) is bonded in a distorted single-bond geometry to one Nb(2) and two equivalent Nb(1) atoms.