The material described by Ni12Al4C crystallizes in the tetragonal P4/mmm space group. There are five inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a single-bond geometry to four equivalent Ni(4), four equivalent Al(1), and one C(1) atom. In the second Ni site, Ni(2) is bonded to four equivalent Ni(4), four equivalent Ni(5), and four equivalent Al(2) atoms to form NiAl4Ni8 cuboctahedra that share corners with eight equivalent Ni(2)Al4Ni8 cuboctahedra, edges with four equivalent Al(1)Ni12 cuboctahedra, edges with four equivalent Al(2)Ni12 cuboctahedra, edges with eight equivalent Ni(4)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Al4Ni8 cuboctahedra, faces with four equivalent Ni(4)Al4Ni8 cuboctahedra, faces with four equivalent Ni(5)Al4Ni8 cuboctahedra, faces with four equivalent Al(2)Ni12 cuboctahedra, and faces with five equivalent Ni(2)Al4Ni8 cuboctahedra. In the third Ni site, Ni(3) is bonded in a linear geometry to four equivalent Al(1) and two equivalent C(1) atoms. In the fourth Ni site, Ni(4) is bonded to two equivalent Ni(1), two equivalent Ni(2), four equivalent Ni(4), two equivalent Al(1), and two equivalent Al(2) atoms to form distorted NiAl4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Al4Ni8 cuboctahedra, corners with four equivalent Ni(5)Al4Ni8 cuboctahedra, corners with two equivalent C(1)Ni6 octahedra, edges with four equivalent Ni(2)Al4Ni8 cuboctahedra, edges with four equivalent Ni(5)Al4Ni8 cuboctahedra, edges with four equivalent Al(1)Ni12 cuboctahedra, edges with four equivalent Al(2)Ni12 cuboctahedra,  a faceface with one Ni(5)Al4Ni8 cuboctahedra, faces with two equivalent Ni(2)Al4Ni8 cuboctahedra, faces with two equivalent Al(1)Ni12 cuboctahedra, faces with two equivalent Al(2)Ni12 cuboctahedra, and faces with eight equivalent Ni(4)Al4Ni8 cuboctahedra. The corner-sharing octahedral tilt angles are 47°. In the fifth Ni site, Ni(5) is bonded to four equivalent Ni(2), four equivalent Ni(5), and four equivalent Al(2) atoms to form distorted NiAl4Ni8 cuboctahedra that share corners with four equivalent Ni(5)Al4Ni8 cuboctahedra, corners with eight equivalent Ni(4)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(4)Al4Ni8 cuboctahedra, edges with eight equivalent Al(2)Ni12 cuboctahedra, faces with two equivalent Ni(4)Al4Ni8 cuboctahedra, faces with four equivalent Ni(2)Al4Ni8 cuboctahedra, faces with four equivalent Al(2)Ni12 cuboctahedra, and faces with eight equivalent Ni(5)Al4Ni8 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Ni(1), four equivalent Ni(3), and four equivalent Ni(4) atoms to form AlNi12 cuboctahedra that share corners with four equivalent Al(2)Ni12 cuboctahedra, corners with eight equivalent Al(1)Ni12 cuboctahedra, edges with four equivalent Ni(2)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(4)Al4Ni8 cuboctahedra,  a faceface with one Al(2)Ni12 cuboctahedra, faces with four equivalent Ni(4)Al4Ni8 cuboctahedra, faces with five equivalent Al(1)Ni12 cuboctahedra, and faces with four equivalent C(1)Ni6 octahedra. In the second Al site, Al(2) is bonded to four equivalent Ni(2), four equivalent Ni(4), and four equivalent Ni(5) atoms to form AlNi12 cuboctahedra that share corners with four equivalent Al(1)Ni12 cuboctahedra, corners with eight equivalent Al(2)Ni12 cuboctahedra, edges with four equivalent Ni(2)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(4)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Al4Ni8 cuboctahedra,  a faceface with one Al(1)Ni12 cuboctahedra, faces with four equivalent Ni(2)Al4Ni8 cuboctahedra, faces with four equivalent Ni(4)Al4Ni8 cuboctahedra, faces with four equivalent Ni(5)Al4Ni8 cuboctahedra, and faces with five equivalent Al(2)Ni12 cuboctahedra. C(1) is bonded to two equivalent Ni(1) and four equivalent Ni(3) atoms to form CNi6 octahedra that share corners with eight equivalent Ni(4)Al4Ni8 cuboctahedra, corners with four equivalent C(1)Ni6 octahedra, and faces with eight equivalent Al(1)Ni12 cuboctahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al4Ni12C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.670
_cell_length_b   3.670
_cell_length_c   14.048
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   189.256
_cell_formula_units_Z   1
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
  Al  Al0  1  0.000  0.000  0.862  1.0
  Al  Al1  1  0.000  0.000  0.138  1.0
  Al  Al2  1  0.000  0.000  0.378  1.0
  Al  Al3  1  0.000  0.000  0.622  1.0
  Ni  Ni4  1  0.500  0.500  0.868  1.0
  Ni  Ni5  1  0.500  0.500  0.132  1.0
  Ni  Ni6  1  0.500  0.500  0.375  1.0
  Ni  Ni7  1  0.500  0.500  0.625  1.0
  Ni  Ni8  1  0.500  0.000  0.000  1.0
  Ni  Ni9  1  0.500  0.000  0.255  1.0
  Ni  Ni10  1  0.500  0.000  0.500  1.0
  Ni  Ni11  1  0.500  0.000  0.745  1.0
  Ni  Ni12  1  0.000  0.500  0.000  1.0
  Ni  Ni13  1  0.000  0.500  0.255  1.0
  Ni  Ni14  1  0.000  0.500  0.500  1.0
  Ni  Ni15  1  0.000  0.500  0.745  1.0
  C  C16  1  0.500  0.500  0.000  1.0
[/CIF]
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The material described by Ni12Al4C crystallizes in the tetragonal P4/mmm space group. There are five inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a single-bond geometry to four equivalent Ni(4), four equivalent Al(1), and one C(1) atom. In the second Ni site, Ni(2) is bonded to four equivalent Ni(4), four equivalent Ni(5), and four equivalent Al(2) atoms to form NiAl4Ni8 cuboctahedra that share corners with eight equivalent Ni(2)Al4Ni8 cuboctahedra, edges with four equivalent Al(1)Ni12 cuboctahedra, edges with four equivalent Al(2)Ni12 cuboctahedra, edges with eight equivalent Ni(4)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Al4Ni8 cuboctahedra, faces with four equivalent Ni(4)Al4Ni8 cuboctahedra, faces with four equivalent Ni(5)Al4Ni8 cuboctahedra, faces with four equivalent Al(2)Ni12 cuboctahedra, and faces with five equivalent Ni(2)Al4Ni8 cuboctahedra. In the third Ni site, Ni(3) is bonded in a linear geometry to four equivalent Al(1) and two equivalent C(1) atoms. In the fourth Ni site, Ni(4) is bonded to two equivalent Ni(1), two equivalent Ni(2), four equivalent Ni(4), two equivalent Al(1), and two equivalent Al(2) atoms to form distorted NiAl4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Al4Ni8 cuboctahedra, corners with four equivalent Ni(5)Al4Ni8 cuboctahedra, corners with two equivalent C(1)Ni6 octahedra, edges with four equivalent Ni(2)Al4Ni8 cuboctahedra, edges with four equivalent Ni(5)Al4Ni8 cuboctahedra, edges with four equivalent Al(1)Ni12 cuboctahedra, edges with four equivalent Al(2)Ni12 cuboctahedra,  a faceface with one Ni(5)Al4Ni8 cuboctahedra, faces with two equivalent Ni(2)Al4Ni8 cuboctahedra, faces with two equivalent Al(1)Ni12 cuboctahedra, faces with two equivalent Al(2)Ni12 cuboctahedra, and faces with eight equivalent Ni(4)Al4Ni8 cuboctahedra. The corner-sharing octahedral tilt angles are 47°. In the fifth Ni site, Ni(5) is bonded to four equivalent Ni(2), four equivalent Ni(5), and four equivalent Al(2) atoms to form distorted NiAl4Ni8 cuboctahedra that share corners with four equivalent Ni(5)Al4Ni8 cuboctahedra, corners with eight equivalent Ni(4)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(4)Al4Ni8 cuboctahedra, edges with eight equivalent Al(2)Ni12 cuboctahedra, faces with two equivalent Ni(4)Al4Ni8 cuboctahedra, faces with four equivalent Ni(2)Al4Ni8 cuboctahedra, faces with four equivalent Al(2)Ni12 cuboctahedra, and faces with eight equivalent Ni(5)Al4Ni8 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Ni(1), four equivalent Ni(3), and four equivalent Ni(4) atoms to form AlNi12 cuboctahedra that share corners with four equivalent Al(2)Ni12 cuboctahedra, corners with eight equivalent Al(1)Ni12 cuboctahedra, edges with four equivalent Ni(2)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(4)Al4Ni8 cuboctahedra,  a faceface with one Al(2)Ni12 cuboctahedra, faces with four equivalent Ni(4)Al4Ni8 cuboctahedra, faces with five equivalent Al(1)Ni12 cuboctahedra, and faces with four equivalent C(1)Ni6 octahedra. In the second Al site, Al(2) is bonded to four equivalent Ni(2), four equivalent Ni(4), and four equivalent Ni(5) atoms to form AlNi12 cuboctahedra that share corners with four equivalent Al(1)Ni12 cuboctahedra, corners with eight equivalent Al(2)Ni12 cuboctahedra, edges with four equivalent Ni(2)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(4)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Al4Ni8 cuboctahedra,  a faceface with one Al(1)Ni12 cuboctahedra, faces with four equivalent Ni(2)Al4Ni8 cuboctahedra, faces with four equivalent Ni(4)Al4Ni8 cuboctahedra, faces with four equivalent Ni(5)Al4Ni8 cuboctahedra, and faces with five equivalent Al(2)Ni12 cuboctahedra. C(1) is bonded to two equivalent Ni(1) and four equivalent Ni(3) atoms to form CNi6 octahedra that share corners with eight equivalent Ni(4)Al4Ni8 cuboctahedra, corners with four equivalent C(1)Ni6 octahedra, and faces with eight equivalent Al(1)Ni12 cuboctahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al4Ni12C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.670
_cell_length_b   3.670
_cell_length_c   14.048
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   189.256
_cell_formula_units_Z   1
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
  Al  Al0  1  0.000  0.000  0.862  1.0
  Al  Al1  1  0.000  0.000  0.138  1.0
  Al  Al2  1  0.000  0.000  0.378  1.0
  Al  Al3  1  0.000  0.000  0.622  1.0
  Ni  Ni4  1  0.500  0.500  0.868  1.0
  Ni  Ni5  1  0.500  0.500  0.132  1.0
  Ni  Ni6  1  0.500  0.500  0.375  1.0
  Ni  Ni7  1  0.500  0.500  0.625  1.0
  Ni  Ni8  1  0.500  0.000  0.000  1.0
  Ni  Ni9  1  0.500  0.000  0.255  1.0
  Ni  Ni10  1  0.500  0.000  0.500  1.0
  Ni  Ni11  1  0.500  0.000  0.745  1.0
  Ni  Ni12  1  0.000  0.500  0.000  1.0
  Ni  Ni13  1  0.000  0.500  0.255  1.0
  Ni  Ni14  1  0.000  0.500  0.500  1.0
  Ni  Ni15  1  0.000  0.500  0.745  1.0
  C  C16  1  0.500  0.500  0.000  1.0
[/CIF]
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