The material described by NiAs2 is Pyrite-like structured and crystallizes in the orthorhombic Pbca space group. Ni(1) is bonded to three equivalent As(1) and three equivalent As(2) atoms to form NiAs6 octahedra that share corners with ten equivalent Ni(1)As6 octahedra, corners with three equivalent As(1)Ni3As tetrahedra, corners with three equivalent As(2)Ni3As tetrahedra, and  an edgeedge with one Ni(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 55-65°. There are two inequivalent As sites. In the first As site, As(1) is bonded to three equivalent Ni(1) and one As(2) atom to form distorted AsNi3As tetrahedra that share corners with three equivalent Ni(1)As6 octahedra, corners with six equivalent As(1)Ni3As tetrahedra, and corners with nine equivalent As(2)Ni3As tetrahedra. The corner-sharing octahedral tilt angles range from 71-80°. In the second As site, As(2) is bonded to three equivalent Ni(1) and one As(1) atom to form distorted AsNi3As tetrahedra that share corners with three equivalent Ni(1)As6 octahedra, corners with four equivalent As(2)Ni3As tetrahedra, corners with nine equivalent As(1)Ni3As tetrahedra, and  an edgeedge with one As(2)Ni3As tetrahedra. The corner-sharing octahedral tilt angles range from 75-83°. is represented by the Crystallographic Information File (CIF) [CIF]
data_NiAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.757
_cell_length_b   5.844
_cell_length_c   11.432
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   384.654
_cell_formula_units_Z   8
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
  Ni  Ni0  1  0.997  0.175  0.372  1.0
  Ni  Ni1  1  0.497  0.325  0.628  1.0
  Ni  Ni2  1  0.003  0.675  0.128  1.0
  Ni  Ni3  1  0.503  0.825  0.872  1.0
  Ni  Ni4  1  0.003  0.825  0.628  1.0
  Ni  Ni5  1  0.503  0.675  0.372  1.0
  Ni  Ni6  1  0.997  0.325  0.872  1.0
  Ni  Ni7  1  0.497  0.175  0.128  1.0
  As  As8  1  0.120  0.055  0.181  1.0
  As  As9  1  0.620  0.445  0.819  1.0
  As  As10  1  0.880  0.555  0.319  1.0
  As  As11  1  0.380  0.945  0.681  1.0
  As  As12  1  0.880  0.945  0.819  1.0
  As  As13  1  0.380  0.555  0.181  1.0
  As  As14  1  0.120  0.445  0.681  1.0
  As  As15  1  0.620  0.055  0.319  1.0
  As  As16  1  0.366  0.311  0.431  1.0
  As  As17  1  0.866  0.189  0.569  1.0
  As  As18  1  0.634  0.811  0.069  1.0
  As  As19  1  0.134  0.689  0.931  1.0
  As  As20  1  0.634  0.689  0.569  1.0
  As  As21  1  0.134  0.811  0.431  1.0
  As  As22  1  0.366  0.189  0.931  1.0
  As  As23  1  0.866  0.311  0.069  1.0
[/CIF]
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The material described by NiAs2 is Pyrite-like structured and crystallizes in the orthorhombic Pbca space group. Ni(1) is bonded to three equivalent As(1) and three equivalent As(2) atoms to form NiAs6 octahedra that share corners with ten equivalent Ni(1)As6 octahedra, corners with three equivalent As(1)Ni3As tetrahedra, corners with three equivalent As(2)Ni3As tetrahedra, and  an edgeedge with one Ni(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 55-65°. There are two inequivalent As sites. In the first As site, As(1) is bonded to three equivalent Ni(1) and one As(2) atom to form distorted AsNi3As tetrahedra that share corners with three equivalent Ni(1)As6 octahedra, corners with six equivalent As(1)Ni3As tetrahedra, and corners with nine equivalent As(2)Ni3As tetrahedra. The corner-sharing octahedral tilt angles range from 71-80°. In the second As site, As(2) is bonded to three equivalent Ni(1) and one As(1) atom to form distorted AsNi3As tetrahedra that share corners with three equivalent Ni(1)As6 octahedra, corners with four equivalent As(2)Ni3As tetrahedra, corners with nine equivalent As(1)Ni3As tetrahedra, and  an edgeedge with one As(2)Ni3As tetrahedra. The corner-sharing octahedral tilt angles range from 75-83°. is represented by the Crystallographic Information File (CIF) [CIF]
data_NiAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.757
_cell_length_b   5.844
_cell_length_c   11.432
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   384.654
_cell_formula_units_Z   8
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
  Ni  Ni0  1  0.997  0.175  0.372  1.0
  Ni  Ni1  1  0.497  0.325  0.628  1.0
  Ni  Ni2  1  0.003  0.675  0.128  1.0
  Ni  Ni3  1  0.503  0.825  0.872  1.0
  Ni  Ni4  1  0.003  0.825  0.628  1.0
  Ni  Ni5  1  0.503  0.675  0.372  1.0
  Ni  Ni6  1  0.997  0.325  0.872  1.0
  Ni  Ni7  1  0.497  0.175  0.128  1.0
  As  As8  1  0.120  0.055  0.181  1.0
  As  As9  1  0.620  0.445  0.819  1.0
  As  As10  1  0.880  0.555  0.319  1.0
  As  As11  1  0.380  0.945  0.681  1.0
  As  As12  1  0.880  0.945  0.819  1.0
  As  As13  1  0.380  0.555  0.181  1.0
  As  As14  1  0.120  0.445  0.681  1.0
  As  As15  1  0.620  0.055  0.319  1.0
  As  As16  1  0.366  0.311  0.431  1.0
  As  As17  1  0.866  0.189  0.569  1.0
  As  As18  1  0.634  0.811  0.069  1.0
  As  As19  1  0.134  0.689  0.931  1.0
  As  As20  1  0.634  0.689  0.569  1.0
  As  As21  1  0.134  0.811  0.431  1.0
  As  As22  1  0.366  0.189  0.931  1.0
  As  As23  1  0.866  0.311  0.069  1.0
[/CIF]
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