data_Na2AsIr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.94
_cell_length_b   9.94
_cell_length_c   9.94
_cell_angle_alpha   16.95
_cell_angle_beta   16.95
_cell_angle_gamma   16.95
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2AsIr
_chemical_formula_sum   'Na2 As1 Ir1'
_cell_volume   72.71
_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
  Na  Na2  1  0.0  0.0  0.04  1.0
  Na  Na3  1  0.0  0.0  0.34  1.0
  As  As0  1  0.0  0.0  0.0  1.0
  Ir  Ir1  1  0.0  0.0  0.69  1.0

data_Na2AsIr
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.07
_cell_length_b   2.93
_cell_length_c   9.94
_cell_angle_alpha   90.0
_cell_angle_beta   99.8
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Na2AsIr
_chemical_formula_sum   'Na4 As2 Ir2'
_cell_volume   145.43
_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
  Na  Na0  2  0.0  0.0  0.66  1.0
  Na  Na1  2  0.0  0.0  0.96  1.0
  As  As2  2  0.0  0.0  0.0  1.0
  Ir  Ir3  2  0.0  0.0  0.31  1.0

Na Na As Ir
Na Na As Ir 0 2 o o o 0 1 o o o 1 1 o + - 1 1 + - o 1 1 + o - 1 2 o o o 2 3 o o - 3 3 o + - 3 3 + - o 3 3 + o - 
Na2IrAs crystallizes in the monoclinic Cm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a single-bond geometry to one Na(2) and one As(1) atom. The Na(1)-Na(2) bond length is 2.93 Å. The Na(1)-As(1) bond length is 0.40 Å. In the second Na site, Na(2) is bonded to one Na(1), six equivalent Na(2), and one Ir(1) atom to form distorted NaNa7Ir hexagonal bipyramids that share corners with six equivalent Na(2)Na7Ir hexagonal bipyramids, edges with six equivalent Ir(1)NaAsIr6 hexagonal bipyramids, and edges with twelve equivalent Na(2)Na7Ir hexagonal bipyramids. All Na(2)-Na(2) bond lengths are 2.93 Å. The Na(2)-Ir(1) bond length is 3.50 Å. Ir(1) is bonded to one Na(2), six equivalent Ir(1), and one As(1) atom to form distorted IrNaAsIr6 hexagonal bipyramids that share corners with six equivalent Ir(1)NaAsIr6 hexagonal bipyramids, edges with six equivalent Na(2)Na7Ir hexagonal bipyramids, and edges with twelve equivalent Ir(1)NaAsIr6 hexagonal bipyramids. All Ir(1)-Ir(1) bond lengths are 2.93 Å. The Ir(1)-As(1) bond length is 3.10 Å. As(1) is bonded in a single-bond geometry to one Na(1) and one Ir(1) atom.