The crystal structure described by FeSi2N3 crystallizes in the orthorhombic Cmc2_1 space group. Fe(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted FeN4 trigonal pyramids that share corners with ten equivalent Si(1)N4 tetrahedra and corners with two equivalent Fe(1)N4 trigonal pyramids. Si(1) is bonded to one N(2) and three equivalent N(1) atoms to form SiN4 tetrahedra that share corners with seven equivalent Si(1)N4 tetrahedra and corners with five equivalent Fe(1)N4 trigonal pyramids. There are two inequivalent N sites. In the first N site, N(2) is bonded to two equivalent Fe(1) and two equivalent Si(1) atoms to form distorted NFe2Si2 trigonal pyramids that share corners with ten equivalent N(1)FeSi3 tetrahedra and corners with two equivalent N(2)Fe2Si2 trigonal pyramids. In the second N site, N(1) is bonded to one Fe(1) and three equivalent Si(1) atoms to form distorted NFeSi3 tetrahedra that share corners with seven equivalent N(1)FeSi3 tetrahedra and corners with five equivalent N(2)Fe2Si2 trigonal pyramids. is represented by the CIF file [CIF]
data_FeSi2N3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.397
_cell_length_b   5.401
_cell_length_c   4.805
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.030
_symmetry_Int_Tables_number   1
_cell_volume   121.271
_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  0.000  0.605  0.477  1.0
  Fe  Fe1  1  0.000  0.395  0.977  1.0
  Si  Si2  1  0.334  0.324  0.500  1.0
  Si  Si3  1  0.666  0.990  0.500  1.0
  Si  Si4  1  0.666  0.676  1.000  1.0
  Si  Si5  1  0.334  0.010  1.000  1.0
  N  N6  1  0.397  0.343  0.863  1.0
  N  N7  1  0.603  0.947  0.863  1.0
  N  N8  1  0.603  0.657  0.363  1.0
  N  N9  1  0.397  0.053  0.363  1.0
  N  N10  1  0.000  0.762  0.886  1.0
  N  N11  1  0.000  0.238  0.386  1.0
[/CIF]
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The crystal structure described by FeSi2N3 crystallizes in the orthorhombic Cmc2_1 space group. Fe(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted FeN4 trigonal pyramids that share corners with ten equivalent Si(1)N4 tetrahedra and corners with two equivalent Fe(1)N4 trigonal pyramids. Si(1) is bonded to one N(2) and three equivalent N(1) atoms to form SiN4 tetrahedra that share corners with seven equivalent Si(1)N4 tetrahedra and corners with five equivalent Fe(1)N4 trigonal pyramids. There are two inequivalent N sites. In the first N site, N(2) is bonded to two equivalent Fe(1) and two equivalent Si(1) atoms to form distorted NFe2Si2 trigonal pyramids that share corners with ten equivalent N(1)FeSi3 tetrahedra and corners with two equivalent N(2)Fe2Si2 trigonal pyramids. In the second N site, N(1) is bonded to one Fe(1) and three equivalent Si(1) atoms to form distorted NFeSi3 tetrahedra that share corners with seven equivalent N(1)FeSi3 tetrahedra and corners with five equivalent N(2)Fe2Si2 trigonal pyramids. is represented by the CIF file [CIF]
data_FeSi2N3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.397
_cell_length_b   5.401
_cell_length_c   4.805
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.030
_symmetry_Int_Tables_number   1
_cell_volume   121.271
_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  0.000  0.605  0.477  1.0
  Fe  Fe1  1  0.000  0.395  0.977  1.0
  Si  Si2  1  0.334  0.324  0.500  1.0
  Si  Si3  1  0.666  0.990  0.500  1.0
  Si  Si4  1  0.666  0.676  1.000  1.0
  Si  Si5  1  0.334  0.010  1.000  1.0
  N  N6  1  0.397  0.343  0.863  1.0
  N  N7  1  0.603  0.947  0.863  1.0
  N  N8  1  0.603  0.657  0.363  1.0
  N  N9  1  0.397  0.053  0.363  1.0
  N  N10  1  0.000  0.762  0.886  1.0
  N  N11  1  0.000  0.238  0.386  1.0
[/CIF]
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