The compound described by Cr3N4 crystallizes in the trigonal P31c space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a distorted see-saw-like geometry to two equivalent N(3) and two equivalent N(4) atoms. In the second Cr site, Cr(2) is bonded in a 5-coordinate geometry to one N(1), one N(2), one N(3), and two equivalent N(4) atoms. There are four inequivalent N sites. In the first N site, N(1) is bonded in a 4-coordinate geometry to three equivalent Cr(2) and one N(2) atom. In the second N site, N(2) is bonded in a 4-coordinate geometry to three equivalent Cr(2) and one N(1) atom. In the third N site, N(3) is bonded in a 3-coordinate geometry to one Cr(2) and two equivalent Cr(1) atoms. In the fourth N site, N(4) is bonded to two equivalent Cr(1) and two equivalent Cr(2) atoms to form corner-sharing NCr4 tetrahedra. is represented by the CIF file [CIF]
data_Cr3N4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.672
_cell_length_b   7.672
_cell_length_c   6.655
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   339.242
_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
  Cr  Cr0  1  0.464  0.100  0.270  1.0
  Cr  Cr1  1  0.636  0.536  0.270  1.0
  Cr  Cr2  1  0.900  0.364  0.270  1.0
  Cr  Cr3  1  0.364  0.900  0.770  1.0
  Cr  Cr4  1  0.100  0.464  0.770  1.0
  Cr  Cr5  1  0.536  0.636  0.770  1.0
  Cr  Cr6  1  0.196  0.241  0.515  1.0
  Cr  Cr7  1  0.045  0.804  0.515  1.0
  Cr  Cr8  1  0.759  0.955  0.515  1.0
  Cr  Cr9  1  0.955  0.759  0.015  1.0
  Cr  Cr10  1  0.241  0.196  0.015  1.0
  Cr  Cr11  1  0.804  0.045  0.015  1.0
  N  N12  1  0.000  0.000  0.363  1.0
  N  N13  1  0.000  0.000  0.863  1.0
  N  N14  1  0.000  0.000  0.669  1.0
  N  N15  1  0.000  0.000  0.169  1.0
  N  N16  1  0.323  0.954  0.502  1.0
  N  N17  1  0.632  0.677  0.502  1.0
  N  N18  1  0.046  0.368  0.502  1.0
  N  N19  1  0.368  0.046  0.002  1.0
  N  N20  1  0.954  0.323  0.002  1.0
  N  N21  1  0.677  0.632  0.002  1.0
  N  N22  1  0.383  0.303  0.285  1.0
  N  N23  1  0.920  0.617  0.285  1.0
  N  N24  1  0.697  0.080  0.285  1.0
  N  N25  1  0.080  0.697  0.785  1.0
  N  N26  1  0.303  0.383  0.785  1.0
  N  N27  1  0.617  0.920  0.785  1.0
[/CIF]
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The compound described by Cr3N4 crystallizes in the trigonal P31c space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a distorted see-saw-like geometry to two equivalent N(3) and two equivalent N(4) atoms. In the second Cr site, Cr(2) is bonded in a 5-coordinate geometry to one N(1), one N(2), one N(3), and two equivalent N(4) atoms. There are four inequivalent N sites. In the first N site, N(1) is bonded in a 4-coordinate geometry to three equivalent Cr(2) and one N(2) atom. In the second N site, N(2) is bonded in a 4-coordinate geometry to three equivalent Cr(2) and one N(1) atom. In the third N site, N(3) is bonded in a 3-coordinate geometry to one Cr(2) and two equivalent Cr(1) atoms. In the fourth N site, N(4) is bonded to two equivalent Cr(1) and two equivalent Cr(2) atoms to form corner-sharing NCr4 tetrahedra. is represented by the CIF file [CIF]
data_Cr3N4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.672
_cell_length_b   7.672
_cell_length_c   6.655
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   339.242
_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
  Cr  Cr0  1  0.464  0.100  0.270  1.0
  Cr  Cr1  1  0.636  0.536  0.270  1.0
  Cr  Cr2  1  0.900  0.364  0.270  1.0
  Cr  Cr3  1  0.364  0.900  0.770  1.0
  Cr  Cr4  1  0.100  0.464  0.770  1.0
  Cr  Cr5  1  0.536  0.636  0.770  1.0
  Cr  Cr6  1  0.196  0.241  0.515  1.0
  Cr  Cr7  1  0.045  0.804  0.515  1.0
  Cr  Cr8  1  0.759  0.955  0.515  1.0
  Cr  Cr9  1  0.955  0.759  0.015  1.0
  Cr  Cr10  1  0.241  0.196  0.015  1.0
  Cr  Cr11  1  0.804  0.045  0.015  1.0
  N  N12  1  0.000  0.000  0.363  1.0
  N  N13  1  0.000  0.000  0.863  1.0
  N  N14  1  0.000  0.000  0.669  1.0
  N  N15  1  0.000  0.000  0.169  1.0
  N  N16  1  0.323  0.954  0.502  1.0
  N  N17  1  0.632  0.677  0.502  1.0
  N  N18  1  0.046  0.368  0.502  1.0
  N  N19  1  0.368  0.046  0.002  1.0
  N  N20  1  0.954  0.323  0.002  1.0
  N  N21  1  0.677  0.632  0.002  1.0
  N  N22  1  0.383  0.303  0.285  1.0
  N  N23  1  0.920  0.617  0.285  1.0
  N  N24  1  0.697  0.080  0.285  1.0
  N  N25  1  0.080  0.697  0.785  1.0
  N  N26  1  0.303  0.383  0.785  1.0
  N  N27  1  0.617  0.920  0.785  1.0
[/CIF]
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