The compound described by Fe3C crystallizes in the tetragonal I-42m space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent C(1) atoms to form a mixture of distorted edge and corner-sharing FeC4 tetrahedra. In the second Fe site, Fe(3) is bonded in a distorted water-like geometry to two equivalent C(1) atoms. In the third Fe site, Fe(2) is bonded in a bent 120 degrees geometry to two equivalent C(1) atoms. C(1) is bonded in a 8-coordinate geometry to two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_Fe3C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.309
_cell_length_b   6.309
_cell_length_c   6.309
_cell_angle_alpha   96.436
_cell_angle_beta   96.436
_cell_angle_gamma   140.880
_symmetry_Int_Tables_number   1
_cell_volume   149.265
_cell_formula_units_Z   4
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  0.856  0.356  1.0
  Fe  Fe1  1  0.500  0.144  0.644  1.0
  Fe  Fe2  1  0.144  0.500  0.644  1.0
  Fe  Fe3  1  0.856  0.500  0.356  1.0
  Fe  Fe4  1  0.994  0.994  0.391  1.0
  Fe  Fe5  1  0.602  0.602  0.609  1.0
  Fe  Fe6  1  0.006  0.398  0.000  1.0
  Fe  Fe7  1  0.398  0.006  0.000  1.0
  Fe  Fe8  1  0.163  0.163  0.804  1.0
  Fe  Fe9  1  0.359  0.359  0.196  1.0
  Fe  Fe10  1  0.837  0.641  0.000  1.0
  Fe  Fe11  1  0.641  0.837  0.000  1.0
  C  C12  1  0.710  0.000  0.710  1.0
  C  C13  1  0.290  0.000  0.290  1.0
  C  C14  1  0.000  0.710  0.710  1.0
  C  C15  1  0.000  0.290  0.290  1.0
[/CIF]
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The compound described by Fe3C crystallizes in the tetragonal I-42m space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent C(1) atoms to form a mixture of distorted edge and corner-sharing FeC4 tetrahedra. In the second Fe site, Fe(3) is bonded in a distorted water-like geometry to two equivalent C(1) atoms. In the third Fe site, Fe(2) is bonded in a bent 120 degrees geometry to two equivalent C(1) atoms. C(1) is bonded in a 8-coordinate geometry to two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_Fe3C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.309
_cell_length_b   6.309
_cell_length_c   6.309
_cell_angle_alpha   96.436
_cell_angle_beta   96.436
_cell_angle_gamma   140.880
_symmetry_Int_Tables_number   1
_cell_volume   149.265
_cell_formula_units_Z   4
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  0.856  0.356  1.0
  Fe  Fe1  1  0.500  0.144  0.644  1.0
  Fe  Fe2  1  0.144  0.500  0.644  1.0
  Fe  Fe3  1  0.856  0.500  0.356  1.0
  Fe  Fe4  1  0.994  0.994  0.391  1.0
  Fe  Fe5  1  0.602  0.602  0.609  1.0
  Fe  Fe6  1  0.006  0.398  0.000  1.0
  Fe  Fe7  1  0.398  0.006  0.000  1.0
  Fe  Fe8  1  0.163  0.163  0.804  1.0
  Fe  Fe9  1  0.359  0.359  0.196  1.0
  Fe  Fe10  1  0.837  0.641  0.000  1.0
  Fe  Fe11  1  0.641  0.837  0.000  1.0
  C  C12  1  0.710  0.000  0.710  1.0
  C  C13  1  0.290  0.000  0.290  1.0
  C  C14  1  0.000  0.710  0.710  1.0
  C  C15  1  0.000  0.290  0.290  1.0
[/CIF]
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