data_CoSiIr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.92
_cell_length_b   3.92
_cell_length_c   3.92
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CoSiIr
_chemical_formula_sum   'Co1 Si1 Ir1'
_cell_volume   42.67
_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
  Co  Co0  1  0.16  0.16  0.16  1.0
  Si  Si2  1  0.0  0.0  0.0  1.0
  Ir  Ir1  1  0.77  0.77  0.77  1.0

data_CoSiIr
_symmetry_space_group_name_H-M   R3m
_cell_length_a   3.92
_cell_length_b   3.92
_cell_length_c   9.61
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CoSiIr
_chemical_formula_sum   'Co3 Si3 Ir3'
_cell_volume   128.01
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Co  Co0  3  0.0  0.0  0.84  1.0
  Si  Si1  3  0.0  0.0  0.0  1.0
  Ir  Ir2  3  0.0  0.0  0.23  1.0

Co Si Ir
Co Si Ir 0 1 o o o 0 2 o - - 0 2 - o - 0 2 - - o 1 2 - o - 1 2 o - - 1 2 - - o 1 2 - - - 
IrCoSi is half-Heusler structured and crystallizes in the trigonal R3m space group. Ir(1) is bonded in a 7-coordinate geometry to three equivalent Co(1) and four equivalent Si(1) atoms. All Ir(1)-Co(1) bond lengths are 2.32 Å. There is one shorter (2.18 Å) and three longer (2.49 Å) Ir(1)-Si(1) bond lengths. Co(1) is bonded in a 4-coordinate geometry to three equivalent Ir(1) and one Si(1) atom. The Co(1)-Si(1) bond length is 1.54 Å. Si(1) is bonded in a 2-coordinate geometry to four equivalent Ir(1) and one Co(1) atom.