The compound described by AlMg3 crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Al(1) atoms to form distorted MgMg8Al4 cuboctahedra that share corners with ten equivalent Mg(1)Mg8Al4 cuboctahedra, edges with two equivalent Mg(1)Mg8Al4 cuboctahedra, edges with four equivalent Mg(2)Mg8Al4 cuboctahedra, edges with eight equivalent Mg(3)Mg10Al2 cuboctahedra, faces with four equivalent Mg(3)Mg10Al2 cuboctahedra, faces with four equivalent Mg(1)Mg8Al4 cuboctahedra, and faces with eight equivalent Mg(2)Mg8Al4 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Al(1) atoms to form distorted MgMg8Al4 cuboctahedra that share corners with eight equivalent Mg(3)Mg10Al2 cuboctahedra, corners with ten equivalent Mg(2)Mg8Al4 cuboctahedra, edges with two equivalent Mg(2)Mg8Al4 cuboctahedra, edges with four equivalent Mg(3)Mg10Al2 cuboctahedra, edges with four equivalent Mg(1)Mg8Al4 cuboctahedra, faces with four equivalent Mg(3)Mg10Al2 cuboctahedra, faces with four equivalent Mg(2)Mg8Al4 cuboctahedra, and faces with eight equivalent Mg(1)Mg8Al4 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Al(1) atoms to form distorted MgMg10Al2 cuboctahedra that share corners with eight equivalent Mg(2)Mg8Al4 cuboctahedra, corners with ten equivalent Mg(3)Mg10Al2 cuboctahedra, edges with two equivalent Mg(3)Mg10Al2 cuboctahedra, edges with four equivalent Mg(2)Mg8Al4 cuboctahedra, edges with eight equivalent Mg(1)Mg8Al4 cuboctahedra, faces with four equivalent Mg(3)Mg10Al2 cuboctahedra, faces with four equivalent Mg(1)Mg8Al4 cuboctahedra, and faces with four equivalent Mg(2)Mg8Al4 cuboctahedra. Al(1) is bonded in a 10-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms. is represented by the CIF file [CIF]
data_Mg3Al
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.146
_cell_length_b   4.890
_cell_length_c   5.340
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   82.153
_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
  Mg  Mg0  1  0.000  0.000  0.669  1.0
  Mg  Mg1  1  0.000  0.500  0.326  1.0
  Mg  Mg2  1  0.500  0.500  0.838  1.0
  Al  Al3  1  0.500  0.000  0.168  1.0
[/CIF]
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The compound described by AlMg3 crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Al(1) atoms to form distorted MgMg8Al4 cuboctahedra that share corners with ten equivalent Mg(1)Mg8Al4 cuboctahedra, edges with two equivalent Mg(1)Mg8Al4 cuboctahedra, edges with four equivalent Mg(2)Mg8Al4 cuboctahedra, edges with eight equivalent Mg(3)Mg10Al2 cuboctahedra, faces with four equivalent Mg(3)Mg10Al2 cuboctahedra, faces with four equivalent Mg(1)Mg8Al4 cuboctahedra, and faces with eight equivalent Mg(2)Mg8Al4 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and four equivalent Al(1) atoms to form distorted MgMg8Al4 cuboctahedra that share corners with eight equivalent Mg(3)Mg10Al2 cuboctahedra, corners with ten equivalent Mg(2)Mg8Al4 cuboctahedra, edges with two equivalent Mg(2)Mg8Al4 cuboctahedra, edges with four equivalent Mg(3)Mg10Al2 cuboctahedra, edges with four equivalent Mg(1)Mg8Al4 cuboctahedra, faces with four equivalent Mg(3)Mg10Al2 cuboctahedra, faces with four equivalent Mg(2)Mg8Al4 cuboctahedra, and faces with eight equivalent Mg(1)Mg8Al4 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Al(1) atoms to form distorted MgMg10Al2 cuboctahedra that share corners with eight equivalent Mg(2)Mg8Al4 cuboctahedra, corners with ten equivalent Mg(3)Mg10Al2 cuboctahedra, edges with two equivalent Mg(3)Mg10Al2 cuboctahedra, edges with four equivalent Mg(2)Mg8Al4 cuboctahedra, edges with eight equivalent Mg(1)Mg8Al4 cuboctahedra, faces with four equivalent Mg(3)Mg10Al2 cuboctahedra, faces with four equivalent Mg(1)Mg8Al4 cuboctahedra, and faces with four equivalent Mg(2)Mg8Al4 cuboctahedra. Al(1) is bonded in a 10-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms. is represented by the CIF file [CIF]
data_Mg3Al
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.146
_cell_length_b   4.890
_cell_length_c   5.340
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   82.153
_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
  Mg  Mg0  1  0.000  0.000  0.669  1.0
  Mg  Mg1  1  0.000  0.500  0.326  1.0
  Mg  Mg2  1  0.500  0.500  0.838  1.0
  Al  Al3  1  0.500  0.000  0.168  1.0
[/CIF]
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