The structure described by Fe2Ni9N8 crystallizes in the monoclinic C2/m space group. Fe(1) is bonded in a trigonal planar geometry to one N(1), one N(2), and one N(3) atom. There are five inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a linear geometry to two equivalent N(4) atoms. In the second Ni site, Ni(2) is bonded in a distorted trigonal non-coplanar geometry to one N(2) and two equivalent N(4) atoms. In the third Ni site, Ni(3) is bonded in a 4-coordinate geometry to one N(3), one N(4), and two equivalent N(2) atoms. In the fourth Ni site, Ni(4) is bonded in a distorted trigonal planar geometry to one N(4) and two equivalent N(1) atoms. In the fifth Ni site, Ni(5) is bonded in a trigonal planar geometry to one N(1) and two equivalent N(3) atoms. There are four inequivalent N sites. In the first N site, N(1) is bonded to one Fe(1), one Ni(5), and two equivalent Ni(4) atoms to form NFeNi3 trigonal pyramids that share corners with two equivalent N(4)Ni5 trigonal bipyramids,  a cornercorner with one N(2)FeNi3 trigonal pyramid, corners with two equivalent N(1)FeNi3 trigonal pyramids, and corners with three equivalent N(3)FeNi3 trigonal pyramids. In the second N site, N(2) is bonded to one Fe(1), one Ni(2), and two equivalent Ni(3) atoms to form distorted NFeNi3 trigonal pyramids that share  a cornercorner with one N(1)FeNi3 trigonal pyramid, corners with two equivalent N(2)FeNi3 trigonal pyramids, corners with three equivalent N(3)FeNi3 trigonal pyramids, and edges with two equivalent N(4)Ni5 trigonal bipyramids. In the third N site, N(3) is bonded to one Fe(1), one Ni(3), and two equivalent Ni(5) atoms to form distorted NFeNi3 trigonal pyramids that share  a cornercorner with one N(4)Ni5 trigonal bipyramid, corners with two equivalent N(3)FeNi3 trigonal pyramids, corners with three equivalent N(1)FeNi3 trigonal pyramids, and corners with three equivalent N(2)FeNi3 trigonal pyramids. In the fourth N site, N(4) is bonded to one Ni(1), one Ni(3), one Ni(4), and two equivalent Ni(2) atoms to form distorted NNi5 trigonal bipyramids that share corners with three equivalent N(4)Ni5 trigonal bipyramids,  a cornercorner with one N(3)FeNi3 trigonal pyramid, corners with two equivalent N(1)FeNi3 trigonal pyramids, and edges with two equivalent N(2)FeNi3 trigonal pyramids. is represented by the CIF file [CIF]
data_Fe2Ni9N8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.029
_cell_length_b   3.398
_cell_length_c   7.259
_cell_angle_alpha   90.000
_cell_angle_beta   63.789
_cell_angle_gamma   80.247
_symmetry_Int_Tables_number   1
_cell_volume   217.966
_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  0.370  0.815  0.831  1.0
  Fe  Fe1  1  0.630  0.185  0.169  1.0
  Ni  Ni2  1  0.000  0.500  0.500  1.0
  Ni  Ni3  1  0.049  0.975  0.795  1.0
  Ni  Ni4  1  0.951  0.025  0.205  1.0
  Ni  Ni5  1  0.716  0.642  0.419  1.0
  Ni  Ni6  1  0.284  0.358  0.581  1.0
  Ni  Ni7  1  0.798  0.601  0.887  1.0
  Ni  Ni8  1  0.202  0.399  0.113  1.0
  Ni  Ni9  1  0.614  0.193  0.734  1.0
  Ni  Ni10  1  0.386  0.807  0.266  1.0
  N  N11  1  0.286  0.857  0.104  1.0
  N  N12  1  0.714  0.143  0.896  1.0
  N  N13  1  0.259  0.871  0.696  1.0
  N  N14  1  0.741  0.129  0.304  1.0
  N  N15  1  0.565  0.717  0.687  1.0
  N  N16  1  0.435  0.283  0.313  1.0
  N  N17  1  0.010  0.495  0.740  1.0
  N  N18  1  0.990  0.505  0.260  1.0
[/CIF]
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The structure described by Fe2Ni9N8 crystallizes in the monoclinic C2/m space group. Fe(1) is bonded in a trigonal planar geometry to one N(1), one N(2), and one N(3) atom. There are five inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a linear geometry to two equivalent N(4) atoms. In the second Ni site, Ni(2) is bonded in a distorted trigonal non-coplanar geometry to one N(2) and two equivalent N(4) atoms. In the third Ni site, Ni(3) is bonded in a 4-coordinate geometry to one N(3), one N(4), and two equivalent N(2) atoms. In the fourth Ni site, Ni(4) is bonded in a distorted trigonal planar geometry to one N(4) and two equivalent N(1) atoms. In the fifth Ni site, Ni(5) is bonded in a trigonal planar geometry to one N(1) and two equivalent N(3) atoms. There are four inequivalent N sites. In the first N site, N(1) is bonded to one Fe(1), one Ni(5), and two equivalent Ni(4) atoms to form NFeNi3 trigonal pyramids that share corners with two equivalent N(4)Ni5 trigonal bipyramids,  a cornercorner with one N(2)FeNi3 trigonal pyramid, corners with two equivalent N(1)FeNi3 trigonal pyramids, and corners with three equivalent N(3)FeNi3 trigonal pyramids. In the second N site, N(2) is bonded to one Fe(1), one Ni(2), and two equivalent Ni(3) atoms to form distorted NFeNi3 trigonal pyramids that share  a cornercorner with one N(1)FeNi3 trigonal pyramid, corners with two equivalent N(2)FeNi3 trigonal pyramids, corners with three equivalent N(3)FeNi3 trigonal pyramids, and edges with two equivalent N(4)Ni5 trigonal bipyramids. In the third N site, N(3) is bonded to one Fe(1), one Ni(3), and two equivalent Ni(5) atoms to form distorted NFeNi3 trigonal pyramids that share  a cornercorner with one N(4)Ni5 trigonal bipyramid, corners with two equivalent N(3)FeNi3 trigonal pyramids, corners with three equivalent N(1)FeNi3 trigonal pyramids, and corners with three equivalent N(2)FeNi3 trigonal pyramids. In the fourth N site, N(4) is bonded to one Ni(1), one Ni(3), one Ni(4), and two equivalent Ni(2) atoms to form distorted NNi5 trigonal bipyramids that share corners with three equivalent N(4)Ni5 trigonal bipyramids,  a cornercorner with one N(3)FeNi3 trigonal pyramid, corners with two equivalent N(1)FeNi3 trigonal pyramids, and edges with two equivalent N(2)FeNi3 trigonal pyramids. is represented by the CIF file [CIF]
data_Fe2Ni9N8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.029
_cell_length_b   3.398
_cell_length_c   7.259
_cell_angle_alpha   90.000
_cell_angle_beta   63.789
_cell_angle_gamma   80.247
_symmetry_Int_Tables_number   1
_cell_volume   217.966
_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  0.370  0.815  0.831  1.0
  Fe  Fe1  1  0.630  0.185  0.169  1.0
  Ni  Ni2  1  0.000  0.500  0.500  1.0
  Ni  Ni3  1  0.049  0.975  0.795  1.0
  Ni  Ni4  1  0.951  0.025  0.205  1.0
  Ni  Ni5  1  0.716  0.642  0.419  1.0
  Ni  Ni6  1  0.284  0.358  0.581  1.0
  Ni  Ni7  1  0.798  0.601  0.887  1.0
  Ni  Ni8  1  0.202  0.399  0.113  1.0
  Ni  Ni9  1  0.614  0.193  0.734  1.0
  Ni  Ni10  1  0.386  0.807  0.266  1.0
  N  N11  1  0.286  0.857  0.104  1.0
  N  N12  1  0.714  0.143  0.896  1.0
  N  N13  1  0.259  0.871  0.696  1.0
  N  N14  1  0.741  0.129  0.304  1.0
  N  N15  1  0.565  0.717  0.687  1.0
  N  N16  1  0.435  0.283  0.313  1.0
  N  N17  1  0.010  0.495  0.740  1.0
  N  N18  1  0.990  0.505  0.260  1.0
[/CIF]
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