The structure described by Cr3N4 is Corundum-like structured and crystallizes in the hexagonal P6_3/m space group. Cr(1) is bonded to two equivalent N(2) and four equivalent N(1) atoms to form a mixture of face, corner, and edge-sharing CrN6 octahedra. The corner-sharing octahedral tilt angles range from 43-49°. There are two inequivalent N sites. In the first N site, N(2) is bonded to six equivalent Cr(1) atoms to form distorted NCr6 pentagonal pyramids that share corners with six equivalent N(1)Cr4 trigonal pyramids, edges with nine equivalent N(1)Cr4 trigonal pyramids, and faces with two equivalent N(2)Cr6 pentagonal pyramids. In the second N site, N(1) is bonded to four equivalent Cr(1) atoms to form NCr4 trigonal pyramids that share corners with two equivalent N(2)Cr6 pentagonal pyramids, corners with eight equivalent N(1)Cr4 trigonal pyramids, edges with three equivalent N(2)Cr6 pentagonal pyramids, and edges with two equivalent N(1)Cr4 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr3N4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.637
_cell_length_b   7.637
_cell_length_c   2.753
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   139.063
_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
  Cr  Cr0  1  0.523  0.654  0.750  1.0
  Cr  Cr1  1  0.131  0.477  0.750  1.0
  Cr  Cr2  1  0.346  0.869  0.750  1.0
  Cr  Cr3  1  0.477  0.346  0.250  1.0
  Cr  Cr4  1  0.869  0.523  0.250  1.0
  Cr  Cr5  1  0.654  0.131  0.250  1.0
  N  N6  1  0.639  0.951  0.750  1.0
  N  N7  1  0.312  0.361  0.750  1.0
  N  N8  1  0.049  0.688  0.750  1.0
  N  N9  1  0.361  0.049  0.250  1.0
  N  N10  1  0.688  0.639  0.250  1.0
  N  N11  1  0.951  0.312  0.250  1.0
  N  N12  1  0.667  0.333  0.750  1.0
  N  N13  1  0.333  0.667  0.250  1.0
[/CIF]
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The structure described by Cr3N4 is Corundum-like structured and crystallizes in the hexagonal P6_3/m space group. Cr(1) is bonded to two equivalent N(2) and four equivalent N(1) atoms to form a mixture of face, corner, and edge-sharing CrN6 octahedra. The corner-sharing octahedral tilt angles range from 43-49°. There are two inequivalent N sites. In the first N site, N(2) is bonded to six equivalent Cr(1) atoms to form distorted NCr6 pentagonal pyramids that share corners with six equivalent N(1)Cr4 trigonal pyramids, edges with nine equivalent N(1)Cr4 trigonal pyramids, and faces with two equivalent N(2)Cr6 pentagonal pyramids. In the second N site, N(1) is bonded to four equivalent Cr(1) atoms to form NCr4 trigonal pyramids that share corners with two equivalent N(2)Cr6 pentagonal pyramids, corners with eight equivalent N(1)Cr4 trigonal pyramids, edges with three equivalent N(2)Cr6 pentagonal pyramids, and edges with two equivalent N(1)Cr4 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr3N4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.637
_cell_length_b   7.637
_cell_length_c   2.753
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   139.063
_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
  Cr  Cr0  1  0.523  0.654  0.750  1.0
  Cr  Cr1  1  0.131  0.477  0.750  1.0
  Cr  Cr2  1  0.346  0.869  0.750  1.0
  Cr  Cr3  1  0.477  0.346  0.250  1.0
  Cr  Cr4  1  0.869  0.523  0.250  1.0
  Cr  Cr5  1  0.654  0.131  0.250  1.0
  N  N6  1  0.639  0.951  0.750  1.0
  N  N7  1  0.312  0.361  0.750  1.0
  N  N8  1  0.049  0.688  0.750  1.0
  N  N9  1  0.361  0.049  0.250  1.0
  N  N10  1  0.688  0.639  0.250  1.0
  N  N11  1  0.951  0.312  0.250  1.0
  N  N12  1  0.667  0.333  0.750  1.0
  N  N13  1  0.333  0.667  0.250  1.0
[/CIF]
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