The structure described by Ni6AlSi crystallizes in the tetragonal P4/mmm space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to eight equivalent Ni(3) and four equivalent Al(1) atoms to form distorted NiAl4Ni8 cuboctahedra that share corners with four equivalent Ni(1)Al4Ni8 cuboctahedra, corners with eight equivalent Ni(2)Si4Ni8 cuboctahedra, edges with eight equivalent Si(1)Ni12 cuboctahedra, edges with sixteen equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Ni(2)Si4Ni8 cuboctahedra, faces with four equivalent Ni(1)Al4Ni8 cuboctahedra, faces with four equivalent Al(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra. In the second Ni site, Ni(2) is bonded to eight equivalent Ni(3) and four equivalent Si(1) atoms to form NiSi4Ni8 cuboctahedra that share corners with four equivalent Ni(2)Si4Ni8 cuboctahedra, corners with eight equivalent Ni(1)Al4Ni8 cuboctahedra, edges with eight equivalent Al(1)Ni12 cuboctahedra, edges with sixteen equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Ni(1)Al4Ni8 cuboctahedra, faces with four equivalent Ni(2)Si4Ni8 cuboctahedra, faces with four equivalent Si(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra. In the third Ni site, Ni(3) is bonded to two equivalent Ni(1), two equivalent Ni(2), four equivalent Ni(3), two equivalent Al(1), and two equivalent Si(1) atoms to form NiAl2Si2Ni8 cuboctahedra that share corners with twelve equivalent Ni(3)Al2Si2Ni8 cuboctahedra, edges with four equivalent Ni(1)Al4Ni8 cuboctahedra, edges with four equivalent Ni(2)Si4Ni8 cuboctahedra, edges with four equivalent Al(1)Ni12 cuboctahedra, edges with four equivalent Si(1)Ni12 cuboctahedra, edges with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Ni(1)Al4Ni8 cuboctahedra, faces with two equivalent Ni(2)Si4Ni8 cuboctahedra, faces with two equivalent Al(1)Ni12 cuboctahedra, faces with two equivalent Si(1)Ni12 cuboctahedra, and faces with ten equivalent Ni(3)Al2Si2Ni8 cuboctahedra. Al(1) is bonded to four equivalent Ni(1) and eight equivalent Ni(3) atoms to form AlNi12 cuboctahedra that share corners with four equivalent Al(1)Ni12 cuboctahedra, corners with eight equivalent Si(1)Ni12 cuboctahedra, edges with eight equivalent Ni(2)Si4Ni8 cuboctahedra, edges with sixteen equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Si(1)Ni12 cuboctahedra, faces with four equivalent Ni(1)Al4Ni8 cuboctahedra, faces with four equivalent Al(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra. Si(1) is bonded to four equivalent Ni(2) and eight equivalent Ni(3) atoms to form SiNi12 cuboctahedra that share corners with four equivalent Si(1)Ni12 cuboctahedra, corners with eight equivalent Al(1)Ni12 cuboctahedra, edges with eight equivalent Ni(1)Al4Ni8 cuboctahedra, edges with sixteen equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Al(1)Ni12 cuboctahedra, faces with four equivalent Ni(2)Si4Ni8 cuboctahedra, faces with four equivalent Si(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlSiNi6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.497
_cell_length_b   3.497
_cell_length_c   6.981
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   85.362
_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  0.000  1.0
  Si  Si1  1  0.000  0.000  0.500  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.500  0.500  0.500  1.0
  Ni  Ni4  1  0.500  0.000  0.257  1.0
  Ni  Ni5  1  0.500  0.000  0.743  1.0
  Ni  Ni6  1  0.000  0.500  0.257  1.0
  Ni  Ni7  1  0.000  0.500  0.743  1.0
[/CIF]
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The structure described by Ni6AlSi crystallizes in the tetragonal P4/mmm space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to eight equivalent Ni(3) and four equivalent Al(1) atoms to form distorted NiAl4Ni8 cuboctahedra that share corners with four equivalent Ni(1)Al4Ni8 cuboctahedra, corners with eight equivalent Ni(2)Si4Ni8 cuboctahedra, edges with eight equivalent Si(1)Ni12 cuboctahedra, edges with sixteen equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Ni(2)Si4Ni8 cuboctahedra, faces with four equivalent Ni(1)Al4Ni8 cuboctahedra, faces with four equivalent Al(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra. In the second Ni site, Ni(2) is bonded to eight equivalent Ni(3) and four equivalent Si(1) atoms to form NiSi4Ni8 cuboctahedra that share corners with four equivalent Ni(2)Si4Ni8 cuboctahedra, corners with eight equivalent Ni(1)Al4Ni8 cuboctahedra, edges with eight equivalent Al(1)Ni12 cuboctahedra, edges with sixteen equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Ni(1)Al4Ni8 cuboctahedra, faces with four equivalent Ni(2)Si4Ni8 cuboctahedra, faces with four equivalent Si(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra. In the third Ni site, Ni(3) is bonded to two equivalent Ni(1), two equivalent Ni(2), four equivalent Ni(3), two equivalent Al(1), and two equivalent Si(1) atoms to form NiAl2Si2Ni8 cuboctahedra that share corners with twelve equivalent Ni(3)Al2Si2Ni8 cuboctahedra, edges with four equivalent Ni(1)Al4Ni8 cuboctahedra, edges with four equivalent Ni(2)Si4Ni8 cuboctahedra, edges with four equivalent Al(1)Ni12 cuboctahedra, edges with four equivalent Si(1)Ni12 cuboctahedra, edges with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Ni(1)Al4Ni8 cuboctahedra, faces with two equivalent Ni(2)Si4Ni8 cuboctahedra, faces with two equivalent Al(1)Ni12 cuboctahedra, faces with two equivalent Si(1)Ni12 cuboctahedra, and faces with ten equivalent Ni(3)Al2Si2Ni8 cuboctahedra. Al(1) is bonded to four equivalent Ni(1) and eight equivalent Ni(3) atoms to form AlNi12 cuboctahedra that share corners with four equivalent Al(1)Ni12 cuboctahedra, corners with eight equivalent Si(1)Ni12 cuboctahedra, edges with eight equivalent Ni(2)Si4Ni8 cuboctahedra, edges with sixteen equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Si(1)Ni12 cuboctahedra, faces with four equivalent Ni(1)Al4Ni8 cuboctahedra, faces with four equivalent Al(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra. Si(1) is bonded to four equivalent Ni(2) and eight equivalent Ni(3) atoms to form SiNi12 cuboctahedra that share corners with four equivalent Si(1)Ni12 cuboctahedra, corners with eight equivalent Al(1)Ni12 cuboctahedra, edges with eight equivalent Ni(1)Al4Ni8 cuboctahedra, edges with sixteen equivalent Ni(3)Al2Si2Ni8 cuboctahedra, faces with two equivalent Al(1)Ni12 cuboctahedra, faces with four equivalent Ni(2)Si4Ni8 cuboctahedra, faces with four equivalent Si(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(3)Al2Si2Ni8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlSiNi6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.497
_cell_length_b   3.497
_cell_length_c   6.981
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   85.362
_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  0.000  1.0
  Si  Si1  1  0.000  0.000  0.500  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.500  0.500  0.500  1.0
  Ni  Ni4  1  0.500  0.000  0.257  1.0
  Ni  Ni5  1  0.500  0.000  0.743  1.0
  Ni  Ni6  1  0.000  0.500  0.257  1.0
  Ni  Ni7  1  0.000  0.500  0.743  1.0
[/CIF]
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