The structure described by IrAs2 crystallizes in the monoclinic P2_1/c space group. Ir(1) is bonded to three equivalent As(1) and three equivalent As(2) atoms to form distorted IrAs6 octahedra that share corners with eight equivalent Ir(1)As6 octahedra, corners with three equivalent As(1)AsIr3 tetrahedra, corners with three equivalent As(2)AsIr3 tetrahedra, and edges with two equivalent Ir(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 54-60°. There are two inequivalent As sites. In the first As site, As(1) is bonded to three equivalent Ir(1) and one As(2) atom to form AsAsIr3 tetrahedra that share corners with three equivalent Ir(1)As6 octahedra, corners with four equivalent As(1)AsIr3 tetrahedra, corners with nine equivalent As(2)AsIr3 tetrahedra, and  an edgeedge with one As(1)AsIr3 tetrahedra. The corner-sharing octahedral tilt angles range from 68-73°. In the second As site, As(2) is bonded to three equivalent Ir(1) and one As(1) atom to form AsAsIr3 tetrahedra that share corners with three equivalent Ir(1)As6 octahedra, corners with four equivalent As(2)AsIr3 tetrahedra, corners with nine equivalent As(1)AsIr3 tetrahedra, and  an edgeedge with one As(2)AsIr3 tetrahedra. The corner-sharing octahedral tilt angles range from 73-78°. is represented by the CIF file [CIF]
data_As2Ir
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.094
_cell_length_b   6.098
_cell_length_c   6.194
_cell_angle_alpha   90.000
_cell_angle_beta   112.833
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   212.135
_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
  As  As0  1  0.154  0.874  0.874  1.0
  As  As1  1  0.846  0.374  0.626  1.0
  As  As2  1  0.846  0.126  0.126  1.0
  As  As3  1  0.154  0.626  0.374  1.0
  As  As4  1  0.338  0.371  0.184  1.0
  As  As5  1  0.662  0.871  0.316  1.0
  As  As6  1  0.662  0.629  0.816  1.0
  As  As7  1  0.338  0.129  0.684  1.0
  Ir  Ir8  1  0.272  0.500  0.792  1.0
  Ir  Ir9  1  0.728  1.000  0.708  1.0
  Ir  Ir10  1  0.728  0.500  0.208  1.0
  Ir  Ir11  1  0.272  0.000  0.292  1.0
[/CIF]
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The structure described by IrAs2 crystallizes in the monoclinic P2_1/c space group. Ir(1) is bonded to three equivalent As(1) and three equivalent As(2) atoms to form distorted IrAs6 octahedra that share corners with eight equivalent Ir(1)As6 octahedra, corners with three equivalent As(1)AsIr3 tetrahedra, corners with three equivalent As(2)AsIr3 tetrahedra, and edges with two equivalent Ir(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 54-60°. There are two inequivalent As sites. In the first As site, As(1) is bonded to three equivalent Ir(1) and one As(2) atom to form AsAsIr3 tetrahedra that share corners with three equivalent Ir(1)As6 octahedra, corners with four equivalent As(1)AsIr3 tetrahedra, corners with nine equivalent As(2)AsIr3 tetrahedra, and  an edgeedge with one As(1)AsIr3 tetrahedra. The corner-sharing octahedral tilt angles range from 68-73°. In the second As site, As(2) is bonded to three equivalent Ir(1) and one As(1) atom to form AsAsIr3 tetrahedra that share corners with three equivalent Ir(1)As6 octahedra, corners with four equivalent As(2)AsIr3 tetrahedra, corners with nine equivalent As(1)AsIr3 tetrahedra, and  an edgeedge with one As(2)AsIr3 tetrahedra. The corner-sharing octahedral tilt angles range from 73-78°. is represented by the CIF file [CIF]
data_As2Ir
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.094
_cell_length_b   6.098
_cell_length_c   6.194
_cell_angle_alpha   90.000
_cell_angle_beta   112.833
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   212.135
_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
  As  As0  1  0.154  0.874  0.874  1.0
  As  As1  1  0.846  0.374  0.626  1.0
  As  As2  1  0.846  0.126  0.126  1.0
  As  As3  1  0.154  0.626  0.374  1.0
  As  As4  1  0.338  0.371  0.184  1.0
  As  As5  1  0.662  0.871  0.316  1.0
  As  As6  1  0.662  0.629  0.816  1.0
  As  As7  1  0.338  0.129  0.684  1.0
  Ir  Ir8  1  0.272  0.500  0.792  1.0
  Ir  Ir9  1  0.728  1.000  0.708  1.0
  Ir  Ir10  1  0.728  0.500  0.208  1.0
  Ir  Ir11  1  0.272  0.000  0.292  1.0
[/CIF]
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