The structure described by NiAs2 is Marcasite structured and crystallizes in the orthorhombic Pnnm space group. Ni(1) is bonded to six equivalent As(1) atoms to form NiAs6 octahedra that share corners with eight equivalent Ni(1)As6 octahedra, corners with six equivalent As(1)Ni3As tetrahedra, and edges with two equivalent Ni(1)As6 octahedra. The corner-sharing octahedral tilt angles are 58°. As(1) 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 thirteen equivalent As(1)Ni3As tetrahedra, and  an edgeedge with one As(1)Ni3As tetrahedra. The corner-sharing octahedral tilt angles range from 74-77°. is represented by the CIF file [CIF]
data_NiAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.564
_cell_length_b   4.742
_cell_length_c   5.766
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   97.454
_cell_formula_units_Z   2
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  0.500  0.500  0.500  1.0
  Ni  Ni1  1  0.000  0.000  0.000  1.0
  As  As2  1  0.500  0.705  0.130  1.0
  As  As3  1  0.500  0.295  0.870  1.0
  As  As4  1  0.000  0.795  0.630  1.0
  As  As5  1  0.000  0.205  0.370  1.0
[/CIF]
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The structure described by NiAs2 is Marcasite structured and crystallizes in the orthorhombic Pnnm space group. Ni(1) is bonded to six equivalent As(1) atoms to form NiAs6 octahedra that share corners with eight equivalent Ni(1)As6 octahedra, corners with six equivalent As(1)Ni3As tetrahedra, and edges with two equivalent Ni(1)As6 octahedra. The corner-sharing octahedral tilt angles are 58°. As(1) 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 thirteen equivalent As(1)Ni3As tetrahedra, and  an edgeedge with one As(1)Ni3As tetrahedra. The corner-sharing octahedral tilt angles range from 74-77°. is represented by the CIF file [CIF]
data_NiAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.564
_cell_length_b   4.742
_cell_length_c   5.766
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   97.454
_cell_formula_units_Z   2
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  0.500  0.500  0.500  1.0
  Ni  Ni1  1  0.000  0.000  0.000  1.0
  As  As2  1  0.500  0.705  0.130  1.0
  As  As3  1  0.500  0.295  0.870  1.0
  As  As4  1  0.000  0.795  0.630  1.0
  As  As5  1  0.000  0.205  0.370  1.0
[/CIF]
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