The material structure described by Mg6NiAl crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ni(1), and two equivalent Al(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Al(1) atoms to form distorted MgMg10Al2 cuboctahedra that share corners with four equivalent Al(1)Mg10Ni2 cuboctahedra, corners with six equivalent Mg(2)Mg10Al2 cuboctahedra, edges with two equivalent Al(1)Mg10Ni2 cuboctahedra, edges with four equivalent Mg(4)Mg10Ni2 cuboctahedra, faces with two equivalent Mg(2)Mg10Al2 cuboctahedra, faces with two equivalent Mg(4)Mg10Ni2 cuboctahedra, faces with two equivalent Al(1)Mg10Ni2 cuboctahedra, and faces with six equivalent Ni(1)Mg10Al2 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ni(1), and two equivalent Al(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ni(1) atoms to form distorted MgMg10Ni2 cuboctahedra that share corners with four equivalent Ni(1)Mg10Al2 cuboctahedra, corners with six equivalent Mg(4)Mg10Ni2 cuboctahedra, edges with two equivalent Ni(1)Mg10Al2 cuboctahedra, edges with four equivalent Mg(2)Mg10Al2 cuboctahedra, faces with two equivalent Mg(2)Mg10Al2 cuboctahedra, faces with two equivalent Mg(4)Mg10Ni2 cuboctahedra, faces with two equivalent Ni(1)Mg10Al2 cuboctahedra, and faces with six equivalent Al(1)Mg10Ni2 cuboctahedra. Ni(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Al(1) atoms to form distorted NiMg10Al2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Ni2 cuboctahedra, corners with six equivalent Ni(1)Mg10Al2 cuboctahedra, edges with two equivalent Mg(4)Mg10Ni2 cuboctahedra, edges with four equivalent Al(1)Mg10Ni2 cuboctahedra, faces with two equivalent Mg(4)Mg10Ni2 cuboctahedra, faces with two equivalent Ni(1)Mg10Al2 cuboctahedra, faces with two equivalent Al(1)Mg10Ni2 cuboctahedra, and faces with six equivalent Mg(2)Mg10Al2 cuboctahedra. Al(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ni(1) atoms to form distorted AlMg10Ni2 cuboctahedra that share corners with four equivalent Mg(2)Mg10Al2 cuboctahedra, corners with six equivalent Al(1)Mg10Ni2 cuboctahedra, edges with two equivalent Mg(2)Mg10Al2 cuboctahedra, edges with four equivalent Ni(1)Mg10Al2 cuboctahedra, faces with two equivalent Mg(2)Mg10Al2 cuboctahedra, faces with two equivalent Ni(1)Mg10Al2 cuboctahedra, faces with two equivalent Al(1)Mg10Ni2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Ni2 cuboctahedra. is represented by the CIF file [CIF]
data_Mg6AlNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.728
_cell_length_b   6.104
_cell_length_c   6.104
_cell_angle_alpha   119.180
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   153.815
_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  0.178  0.822  1.0
  Mg  Mg1  1  0.000  0.648  0.826  1.0
  Mg  Mg2  1  1.000  0.174  0.352  1.0
  Mg  Mg3  1  0.000  0.667  0.333  1.0
  Mg  Mg4  1  0.500  0.847  0.666  1.0
  Mg  Mg5  1  0.500  0.334  0.153  1.0
  Mg  Mg6  1  0.500  0.836  0.164  1.0
  Ni  Ni7  1  0.500  0.317  0.683  1.0
[/CIF]
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The material structure described by Mg6NiAl crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ni(1), and two equivalent Al(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Al(1) atoms to form distorted MgMg10Al2 cuboctahedra that share corners with four equivalent Al(1)Mg10Ni2 cuboctahedra, corners with six equivalent Mg(2)Mg10Al2 cuboctahedra, edges with two equivalent Al(1)Mg10Ni2 cuboctahedra, edges with four equivalent Mg(4)Mg10Ni2 cuboctahedra, faces with two equivalent Mg(2)Mg10Al2 cuboctahedra, faces with two equivalent Mg(4)Mg10Ni2 cuboctahedra, faces with two equivalent Al(1)Mg10Ni2 cuboctahedra, and faces with six equivalent Ni(1)Mg10Al2 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ni(1), and two equivalent Al(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ni(1) atoms to form distorted MgMg10Ni2 cuboctahedra that share corners with four equivalent Ni(1)Mg10Al2 cuboctahedra, corners with six equivalent Mg(4)Mg10Ni2 cuboctahedra, edges with two equivalent Ni(1)Mg10Al2 cuboctahedra, edges with four equivalent Mg(2)Mg10Al2 cuboctahedra, faces with two equivalent Mg(2)Mg10Al2 cuboctahedra, faces with two equivalent Mg(4)Mg10Ni2 cuboctahedra, faces with two equivalent Ni(1)Mg10Al2 cuboctahedra, and faces with six equivalent Al(1)Mg10Ni2 cuboctahedra. Ni(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Al(1) atoms to form distorted NiMg10Al2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Ni2 cuboctahedra, corners with six equivalent Ni(1)Mg10Al2 cuboctahedra, edges with two equivalent Mg(4)Mg10Ni2 cuboctahedra, edges with four equivalent Al(1)Mg10Ni2 cuboctahedra, faces with two equivalent Mg(4)Mg10Ni2 cuboctahedra, faces with two equivalent Ni(1)Mg10Al2 cuboctahedra, faces with two equivalent Al(1)Mg10Ni2 cuboctahedra, and faces with six equivalent Mg(2)Mg10Al2 cuboctahedra. Al(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ni(1) atoms to form distorted AlMg10Ni2 cuboctahedra that share corners with four equivalent Mg(2)Mg10Al2 cuboctahedra, corners with six equivalent Al(1)Mg10Ni2 cuboctahedra, edges with two equivalent Mg(2)Mg10Al2 cuboctahedra, edges with four equivalent Ni(1)Mg10Al2 cuboctahedra, faces with two equivalent Mg(2)Mg10Al2 cuboctahedra, faces with two equivalent Ni(1)Mg10Al2 cuboctahedra, faces with two equivalent Al(1)Mg10Ni2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Ni2 cuboctahedra. is represented by the CIF file [CIF]
data_Mg6AlNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.728
_cell_length_b   6.104
_cell_length_c   6.104
_cell_angle_alpha   119.180
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   153.815
_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  0.178  0.822  1.0
  Mg  Mg1  1  0.000  0.648  0.826  1.0
  Mg  Mg2  1  1.000  0.174  0.352  1.0
  Mg  Mg3  1  0.000  0.667  0.333  1.0
  Mg  Mg4  1  0.500  0.847  0.666  1.0
  Mg  Mg5  1  0.500  0.334  0.153  1.0
  Mg  Mg6  1  0.500  0.836  0.164  1.0
  Ni  Ni7  1  0.500  0.317  0.683  1.0
[/CIF]
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