data_MgZnIr2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.94
_cell_length_b   3.94
_cell_length_c   3.81
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgZnIr2
_chemical_formula_sum   'Mg1 Zn1 Ir2'
_cell_volume   59.13
_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
  Mg  Mg2  1  0.0  0.0  0.0  1.0
  Zn  Zn3  1  0.97  0.97  0.0  1.0
  Ir  Ir0  1  0.97  0.0  0.9  1.0
  Ir  Ir1  1  0.0  0.97  0.9  1.0

data_MgZnIr2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.57
_cell_length_b   5.57
_cell_length_c   3.81
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   MgZnIr2
_chemical_formula_sum   'Mg2 Zn2 Ir4'
_cell_volume   118.26
_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
  Mg  Mg0  2  0.0  0.0  0.0  1.0
  Zn  Zn1  2  0.47  0.5  -0.0  1.0
  Ir  Ir2  4  0.49  0.49  0.9  1.0

Mg Zn Ir Ir
Mg Zn Ir Ir 0 1 - - o 2 3 + - o 
MgIr2Zn is alpha Po structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two MgIr2Zn clusters. Mg(1) is bonded in a distorted single-bond geometry to two equivalent Ir(1) and one Zn(1) atom. Both Mg(1)-Ir(1) bond lengths are 0.38 Å. The Mg(1)-Zn(1) bond length is 0.17 Å. Ir(1) is bonded in a 3-coordinate geometry to one Mg(1), one Ir(1), and one Zn(1) atom. The Ir(1)-Ir(1) bond length is 0.17 Å. The Ir(1)-Zn(1) bond length is 0.38 Å. Zn(1) is bonded in a distorted single-bond geometry to one Mg(1) and two equivalent Ir(1) atoms.