The crystal structure described by Nb3Cr3C crystallizes in the cubic Fd-3m space group. Nb(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Cr(1), four equivalent Cr(2), and two equivalent C(1) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(2) is bonded to six equivalent Nb(1), three equivalent Cr(1), and three equivalent Cr(2) atoms to form distorted CrNb6Cr6 cuboctahedra that share corners with three equivalent Cr(1)Nb6Cr6 cuboctahedra, corners with six equivalent Cr(2)Nb6Cr6 cuboctahedra, corners with three equivalent C(1)Nb6 octahedra, faces with four equivalent Cr(1)Nb6Cr6 cuboctahedra, faces with nine equivalent Cr(2)Nb6Cr6 cuboctahedra, and faces with three equivalent C(1)Nb6 octahedra. The corner-sharing octahedral tilt angles are 43°. In the second Cr site, Cr(1) is bonded to six equivalent Nb(1) and six equivalent Cr(2) atoms to form CrNb6Cr6 cuboctahedra that share corners with six equivalent Cr(2)Nb6Cr6 cuboctahedra, edges with six equivalent C(1)Nb6 octahedra, faces with six equivalent Cr(1)Nb6Cr6 cuboctahedra, and faces with eight equivalent Cr(2)Nb6Cr6 cuboctahedra. C(1) is bonded to six equivalent Nb(1) atoms to form CNb6 octahedra that share corners with six equivalent Cr(2)Nb6Cr6 cuboctahedra, corners with six equivalent C(1)Nb6 octahedra, edges with six equivalent Cr(1)Nb6Cr6 cuboctahedra, and faces with six equivalent Cr(2)Nb6Cr6 cuboctahedra. The corner-sharing octahedral tilt angles are 42°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb3Cr3C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.178
_cell_length_b   8.178
_cell_length_c   8.178
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   386.690
_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
  Nb  Nb0  1  0.558  0.558  0.942  1.0
  Nb  Nb1  1  0.942  0.942  0.558  1.0
  Nb  Nb2  1  0.692  0.692  0.308  1.0
  Nb  Nb3  1  0.308  0.692  0.692  1.0
  Nb  Nb4  1  0.692  0.308  0.308  1.0
  Nb  Nb5  1  0.308  0.308  0.692  1.0
  Nb  Nb6  1  0.558  0.942  0.558  1.0
  Nb  Nb7  1  0.308  0.692  0.308  1.0
  Nb  Nb8  1  0.942  0.558  0.942  1.0
  Nb  Nb9  1  0.942  0.558  0.558  1.0
  Nb  Nb10  1  0.692  0.308  0.692  1.0
  Nb  Nb11  1  0.558  0.942  0.942  1.0
  Cr  Cr12  1  0.125  0.125  0.625  1.0
  Cr  Cr13  1  0.235  0.922  0.922  1.0
  Cr  Cr14  1  0.922  0.235  0.922  1.0
  Cr  Cr15  1  0.328  0.328  0.328  1.0
  Cr  Cr16  1  0.328  0.015  0.328  1.0
  Cr  Cr17  1  0.328  0.328  0.015  1.0
  Cr  Cr18  1  0.015  0.328  0.328  1.0
  Cr  Cr19  1  0.922  0.922  0.922  1.0
  Cr  Cr20  1  0.125  0.625  0.125  1.0
  Cr  Cr21  1  0.625  0.125  0.125  1.0
  Cr  Cr22  1  0.125  0.125  0.125  1.0
  Cr  Cr23  1  0.922  0.922  0.235  1.0
  C  C24  1  0.625  0.625  0.125  1.0
  C  C25  1  0.125  0.625  0.625  1.0
  C  C26  1  0.625  0.125  0.625  1.0
  C  C27  1  0.625  0.625  0.625  1.0
[/CIF]
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The crystal structure described by Nb3Cr3C crystallizes in the cubic Fd-3m space group. Nb(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Cr(1), four equivalent Cr(2), and two equivalent C(1) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(2) is bonded to six equivalent Nb(1), three equivalent Cr(1), and three equivalent Cr(2) atoms to form distorted CrNb6Cr6 cuboctahedra that share corners with three equivalent Cr(1)Nb6Cr6 cuboctahedra, corners with six equivalent Cr(2)Nb6Cr6 cuboctahedra, corners with three equivalent C(1)Nb6 octahedra, faces with four equivalent Cr(1)Nb6Cr6 cuboctahedra, faces with nine equivalent Cr(2)Nb6Cr6 cuboctahedra, and faces with three equivalent C(1)Nb6 octahedra. The corner-sharing octahedral tilt angles are 43°. In the second Cr site, Cr(1) is bonded to six equivalent Nb(1) and six equivalent Cr(2) atoms to form CrNb6Cr6 cuboctahedra that share corners with six equivalent Cr(2)Nb6Cr6 cuboctahedra, edges with six equivalent C(1)Nb6 octahedra, faces with six equivalent Cr(1)Nb6Cr6 cuboctahedra, and faces with eight equivalent Cr(2)Nb6Cr6 cuboctahedra. C(1) is bonded to six equivalent Nb(1) atoms to form CNb6 octahedra that share corners with six equivalent Cr(2)Nb6Cr6 cuboctahedra, corners with six equivalent C(1)Nb6 octahedra, edges with six equivalent Cr(1)Nb6Cr6 cuboctahedra, and faces with six equivalent Cr(2)Nb6Cr6 cuboctahedra. The corner-sharing octahedral tilt angles are 42°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb3Cr3C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.178
_cell_length_b   8.178
_cell_length_c   8.178
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   386.690
_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
  Nb  Nb0  1  0.558  0.558  0.942  1.0
  Nb  Nb1  1  0.942  0.942  0.558  1.0
  Nb  Nb2  1  0.692  0.692  0.308  1.0
  Nb  Nb3  1  0.308  0.692  0.692  1.0
  Nb  Nb4  1  0.692  0.308  0.308  1.0
  Nb  Nb5  1  0.308  0.308  0.692  1.0
  Nb  Nb6  1  0.558  0.942  0.558  1.0
  Nb  Nb7  1  0.308  0.692  0.308  1.0
  Nb  Nb8  1  0.942  0.558  0.942  1.0
  Nb  Nb9  1  0.942  0.558  0.558  1.0
  Nb  Nb10  1  0.692  0.308  0.692  1.0
  Nb  Nb11  1  0.558  0.942  0.942  1.0
  Cr  Cr12  1  0.125  0.125  0.625  1.0
  Cr  Cr13  1  0.235  0.922  0.922  1.0
  Cr  Cr14  1  0.922  0.235  0.922  1.0
  Cr  Cr15  1  0.328  0.328  0.328  1.0
  Cr  Cr16  1  0.328  0.015  0.328  1.0
  Cr  Cr17  1  0.328  0.328  0.015  1.0
  Cr  Cr18  1  0.015  0.328  0.328  1.0
  Cr  Cr19  1  0.922  0.922  0.922  1.0
  Cr  Cr20  1  0.125  0.625  0.125  1.0
  Cr  Cr21  1  0.625  0.125  0.125  1.0
  Cr  Cr22  1  0.125  0.125  0.125  1.0
  Cr  Cr23  1  0.922  0.922  0.235  1.0
  C  C24  1  0.625  0.625  0.125  1.0
  C  C25  1  0.125  0.625  0.625  1.0
  C  C26  1  0.625  0.125  0.625  1.0
  C  C27  1  0.625  0.625  0.625  1.0
[/CIF]
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