The material structure described by Fe3NiAs8 crystallizes in the monoclinic P2/m space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one As(1), one As(2), two equivalent As(3), and two equivalent As(4) atoms to form FeAs6 octahedra that share corners with four equivalent Fe(2)As6 octahedra, corners with four equivalent Ni(1)As6 octahedra, and edges with two equivalent Fe(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 53-55°. In the second Fe site, Fe(2) is bonded to two equivalent As(3) and four equivalent As(1) atoms to form a mixture of corner and edge-sharing FeAs6 octahedra. The corner-sharing octahedral tilt angles range from 53-54°. Ni(1) is bonded to two equivalent As(4) and four equivalent As(2) atoms to form NiAs6 octahedra that share corners with eight equivalent Fe(1)As6 octahedra and edges with two equivalent Ni(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 53-55°. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Fe(2) atoms. In the second As site, As(2) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Ni(1) atoms. In the third As site, As(3) is bonded in a 3-coordinate geometry to one Fe(2) and two equivalent Fe(1) atoms. In the fourth As site, As(4) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Ni(1) atom. is represented by the CIF card [CIF]
data_Fe3NiAs8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.979
_cell_length_b   5.198
_cell_length_c   11.877
_cell_angle_alpha   90.072
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   183.922
_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
  Fe  Fe0  1  0.500  0.501  0.251  1.0
  Fe  Fe1  1  0.500  0.499  0.749  1.0
  Fe  Fe2  1  0.000  0.000  0.000  1.0
  Ni  Ni3  1  0.000  0.000  0.500  1.0
  As  As4  1  0.500  0.319  0.069  1.0
  As  As5  1  0.500  0.323  0.570  1.0
  As  As6  1  0.500  0.677  0.430  1.0
  As  As7  1  0.500  0.681  0.931  1.0
  As  As8  1  0.000  0.814  0.181  1.0
  As  As9  1  0.000  0.818  0.686  1.0
  As  As10  1  0.000  0.182  0.314  1.0
  As  As11  1  0.000  0.186  0.819  1.0
[/CIF]
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The material structure described by Fe3NiAs8 crystallizes in the monoclinic P2/m space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one As(1), one As(2), two equivalent As(3), and two equivalent As(4) atoms to form FeAs6 octahedra that share corners with four equivalent Fe(2)As6 octahedra, corners with four equivalent Ni(1)As6 octahedra, and edges with two equivalent Fe(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 53-55°. In the second Fe site, Fe(2) is bonded to two equivalent As(3) and four equivalent As(1) atoms to form a mixture of corner and edge-sharing FeAs6 octahedra. The corner-sharing octahedral tilt angles range from 53-54°. Ni(1) is bonded to two equivalent As(4) and four equivalent As(2) atoms to form NiAs6 octahedra that share corners with eight equivalent Fe(1)As6 octahedra and edges with two equivalent Ni(1)As6 octahedra. The corner-sharing octahedral tilt angles range from 53-55°. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Fe(2) atoms. In the second As site, As(2) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Ni(1) atoms. In the third As site, As(3) is bonded in a 3-coordinate geometry to one Fe(2) and two equivalent Fe(1) atoms. In the fourth As site, As(4) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Ni(1) atom. is represented by the CIF card [CIF]
data_Fe3NiAs8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.979
_cell_length_b   5.198
_cell_length_c   11.877
_cell_angle_alpha   90.072
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   183.922
_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
  Fe  Fe0  1  0.500  0.501  0.251  1.0
  Fe  Fe1  1  0.500  0.499  0.749  1.0
  Fe  Fe2  1  0.000  0.000  0.000  1.0
  Ni  Ni3  1  0.000  0.000  0.500  1.0
  As  As4  1  0.500  0.319  0.069  1.0
  As  As5  1  0.500  0.323  0.570  1.0
  As  As6  1  0.500  0.677  0.430  1.0
  As  As7  1  0.500  0.681  0.931  1.0
  As  As8  1  0.000  0.814  0.181  1.0
  As  As9  1  0.000  0.818  0.686  1.0
  As  As10  1  0.000  0.182  0.314  1.0
  As  As11  1  0.000  0.186  0.819  1.0
[/CIF]
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