The crystal structure described by Fe(NiAs)2 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 5-coordinate geometry to one As(2) and four equivalent As(3) atoms. In the second Fe site, Fe(2) is bonded in a 5-coordinate geometry to one As(1) and four equivalent As(3) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 4-coordinate geometry to one As(1), one As(2), and two equivalent As(3) atoms. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to one As(1), one As(2), and two equivalent As(3) atoms. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to two equivalent Fe(2), two equivalent Ni(1), and four equivalent Ni(2) atoms. In the second As site, As(2) is bonded in a 7-coordinate geometry to one Fe(1), two equivalent Ni(1), and four equivalent Ni(2) atoms. In the third As site, As(3) is bonded in a distorted hexagonal planar geometry to one Fe(1), two equivalent Fe(2), one Ni(1), and two equivalent Ni(2) atoms. is represented by the CIF file [CIF]
data_Fe(NiAs)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.959
_cell_length_b   6.959
_cell_length_c   6.959
_cell_angle_alpha   128.591
_cell_angle_beta   120.166
_cell_angle_gamma   82.746
_symmetry_Int_Tables_number   1
_cell_volume   218.865
_cell_formula_units_Z   3
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
  Fe  Fe0  1  0.500  0.853  0.353  1.0
  Fe  Fe1  1  0.793  0.241  0.449  1.0
  Fe  Fe2  1  0.207  0.656  0.449  1.0
  Ni  Ni3  1  0.748  0.505  0.252  1.0
  Ni  Ni4  1  0.252  0.505  0.757  1.0
  Ni  Ni5  1  0.378  0.249  0.372  1.0
  Ni  Ni6  1  0.877  0.249  0.872  1.0
  Ni  Ni7  1  0.123  0.995  0.372  1.0
  Ni  Ni8  1  0.622  0.995  0.872  1.0
  As  As9  1  0.000  0.250  0.250  1.0
  As  As10  1  0.500  0.255  0.755  1.0
  As  As11  1  0.416  0.916  1.000  1.0
  As  As12  1  0.916  0.916  0.499  1.0
  As  As13  1  0.084  0.583  1.000  1.0
  As  As14  1  0.584  0.583  0.499  1.0
[/CIF]
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The crystal structure described by Fe(NiAs)2 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 5-coordinate geometry to one As(2) and four equivalent As(3) atoms. In the second Fe site, Fe(2) is bonded in a 5-coordinate geometry to one As(1) and four equivalent As(3) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 4-coordinate geometry to one As(1), one As(2), and two equivalent As(3) atoms. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to one As(1), one As(2), and two equivalent As(3) atoms. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to two equivalent Fe(2), two equivalent Ni(1), and four equivalent Ni(2) atoms. In the second As site, As(2) is bonded in a 7-coordinate geometry to one Fe(1), two equivalent Ni(1), and four equivalent Ni(2) atoms. In the third As site, As(3) is bonded in a distorted hexagonal planar geometry to one Fe(1), two equivalent Fe(2), one Ni(1), and two equivalent Ni(2) atoms. is represented by the CIF file [CIF]
data_Fe(NiAs)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.959
_cell_length_b   6.959
_cell_length_c   6.959
_cell_angle_alpha   128.591
_cell_angle_beta   120.166
_cell_angle_gamma   82.746
_symmetry_Int_Tables_number   1
_cell_volume   218.865
_cell_formula_units_Z   3
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
  Fe  Fe0  1  0.500  0.853  0.353  1.0
  Fe  Fe1  1  0.793  0.241  0.449  1.0
  Fe  Fe2  1  0.207  0.656  0.449  1.0
  Ni  Ni3  1  0.748  0.505  0.252  1.0
  Ni  Ni4  1  0.252  0.505  0.757  1.0
  Ni  Ni5  1  0.378  0.249  0.372  1.0
  Ni  Ni6  1  0.877  0.249  0.872  1.0
  Ni  Ni7  1  0.123  0.995  0.372  1.0
  Ni  Ni8  1  0.622  0.995  0.872  1.0
  As  As9  1  0.000  0.250  0.250  1.0
  As  As10  1  0.500  0.255  0.755  1.0
  As  As11  1  0.416  0.916  1.000  1.0
  As  As12  1  0.916  0.916  0.499  1.0
  As  As13  1  0.084  0.583  1.000  1.0
  As  As14  1  0.584  0.583  0.499  1.0
[/CIF]
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