The material described by Fe3SiN4 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one N(2), one N(3), and two equivalent N(1) atoms to form distorted FeN4 tetrahedra that share corners with two equivalent Fe(2)N4 tetrahedra, corners with two equivalent Si(1)N4 tetrahedra, corners with four equivalent Fe(1)N4 tetrahedra,  an edgeedge with one Fe(2)N4 tetrahedra, and  an edgeedge with one Si(1)N4 tetrahedra. In the second Fe site, Fe(2) is bonded to one N(2), one N(3), and two equivalent N(1) atoms to form distorted FeN4 tetrahedra that share corners with four equivalent Fe(1)N4 tetrahedra, corners with four equivalent Si(1)N4 tetrahedra, and edges with two equivalent Fe(1)N4 tetrahedra. Si(1) is bonded to one N(2), one N(3), and two equivalent N(1) atoms to form SiN4 tetrahedra that share corners with four equivalent Fe(1)N4 tetrahedra, corners with four equivalent Fe(2)N4 tetrahedra, and edges with two equivalent Fe(1)N4 tetrahedra. There are three inequivalent N sites. In the first N site, N(1) is bonded to one Fe(2), two equivalent Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing NFe3Si trigonal pyramids. In the second N site, N(2) is bonded to one Fe(2), two equivalent Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing NFe3Si trigonal pyramids. In the third N site, N(3) is bonded to one Fe(2), two equivalent Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing NFe3Si trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe3SiN4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.228
_cell_length_b   4.767
_cell_length_c   5.975
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   177.403
_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
  Fe  Fe0  1  0.760  0.659  0.288  1.0
  Fe  Fe1  1  0.240  0.659  0.288  1.0
  Fe  Fe2  1  0.740  0.341  0.788  1.0
  Fe  Fe3  1  0.260  0.341  0.788  1.0
  Fe  Fe4  1  0.500  0.819  0.001  1.0
  Fe  Fe5  1  0.000  0.181  0.501  1.0
  Si  Si6  1  0.000  0.855  0.985  1.0
  Si  Si7  1  0.500  0.145  0.485  1.0
  N  N8  1  0.730  0.350  0.464  1.0
  N  N9  1  0.270  0.350  0.464  1.0
  N  N10  1  0.770  0.650  0.964  1.0
  N  N11  1  0.230  0.650  0.964  1.0
  N  N12  1  0.500  0.853  0.317  1.0
  N  N13  1  0.000  0.147  0.817  1.0
  N  N14  1  0.500  0.090  0.778  1.0
  N  N15  1  0.000  0.910  0.278  1.0
[/CIF]
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The material described by Fe3SiN4 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one N(2), one N(3), and two equivalent N(1) atoms to form distorted FeN4 tetrahedra that share corners with two equivalent Fe(2)N4 tetrahedra, corners with two equivalent Si(1)N4 tetrahedra, corners with four equivalent Fe(1)N4 tetrahedra,  an edgeedge with one Fe(2)N4 tetrahedra, and  an edgeedge with one Si(1)N4 tetrahedra. In the second Fe site, Fe(2) is bonded to one N(2), one N(3), and two equivalent N(1) atoms to form distorted FeN4 tetrahedra that share corners with four equivalent Fe(1)N4 tetrahedra, corners with four equivalent Si(1)N4 tetrahedra, and edges with two equivalent Fe(1)N4 tetrahedra. Si(1) is bonded to one N(2), one N(3), and two equivalent N(1) atoms to form SiN4 tetrahedra that share corners with four equivalent Fe(1)N4 tetrahedra, corners with four equivalent Fe(2)N4 tetrahedra, and edges with two equivalent Fe(1)N4 tetrahedra. There are three inequivalent N sites. In the first N site, N(1) is bonded to one Fe(2), two equivalent Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing NFe3Si trigonal pyramids. In the second N site, N(2) is bonded to one Fe(2), two equivalent Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing NFe3Si trigonal pyramids. In the third N site, N(3) is bonded to one Fe(2), two equivalent Fe(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing NFe3Si trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe3SiN4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.228
_cell_length_b   4.767
_cell_length_c   5.975
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   177.403
_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
  Fe  Fe0  1  0.760  0.659  0.288  1.0
  Fe  Fe1  1  0.240  0.659  0.288  1.0
  Fe  Fe2  1  0.740  0.341  0.788  1.0
  Fe  Fe3  1  0.260  0.341  0.788  1.0
  Fe  Fe4  1  0.500  0.819  0.001  1.0
  Fe  Fe5  1  0.000  0.181  0.501  1.0
  Si  Si6  1  0.000  0.855  0.985  1.0
  Si  Si7  1  0.500  0.145  0.485  1.0
  N  N8  1  0.730  0.350  0.464  1.0
  N  N9  1  0.270  0.350  0.464  1.0
  N  N10  1  0.770  0.650  0.964  1.0
  N  N11  1  0.230  0.650  0.964  1.0
  N  N12  1  0.500  0.853  0.317  1.0
  N  N13  1  0.000  0.147  0.817  1.0
  N  N14  1  0.500  0.090  0.778  1.0
  N  N15  1  0.000  0.910  0.278  1.0
[/CIF]
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