The crystal structure described by Al3Mg is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Mg(1) is bonded to twelve equivalent Al(1) atoms to form MgAl12 cuboctahedra that share corners with six equivalent Mg(1)Al12 cuboctahedra, corners with twelve equivalent Al(1)Mg4Al8 cuboctahedra, edges with eighteen equivalent Al(1)Mg4Al8 cuboctahedra, faces with eight equivalent Mg(1)Al12 cuboctahedra, and faces with twelve equivalent Al(1)Mg4Al8 cuboctahedra. Al(1) is bonded to four equivalent Mg(1) and eight equivalent Al(1) atoms to form distorted AlMg4Al8 cuboctahedra that share corners with four equivalent Mg(1)Al12 cuboctahedra, corners with fourteen equivalent Al(1)Mg4Al8 cuboctahedra, edges with six equivalent Mg(1)Al12 cuboctahedra, edges with twelve equivalent Al(1)Mg4Al8 cuboctahedra, faces with four equivalent Mg(1)Al12 cuboctahedra, and faces with sixteen equivalent Al(1)Mg4Al8 cuboctahedra. is represented by the CIF card [CIF]
data_MgAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.849
_cell_length_b   5.849
_cell_length_c   4.666
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   138.237
_cell_formula_units_Z   2
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  0.667  0.333  0.250  1.0
  Mg  Mg1  1  0.333  0.667  0.750  1.0
  Al  Al2  1  0.161  0.322  0.250  1.0
  Al  Al3  1  0.678  0.839  0.250  1.0
  Al  Al4  1  0.161  0.839  0.250  1.0
  Al  Al5  1  0.322  0.161  0.750  1.0
  Al  Al6  1  0.839  0.161  0.750  1.0
  Al  Al7  1  0.839  0.678  0.750  1.0
[/CIF]
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The crystal structure described by Al3Mg is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Mg(1) is bonded to twelve equivalent Al(1) atoms to form MgAl12 cuboctahedra that share corners with six equivalent Mg(1)Al12 cuboctahedra, corners with twelve equivalent Al(1)Mg4Al8 cuboctahedra, edges with eighteen equivalent Al(1)Mg4Al8 cuboctahedra, faces with eight equivalent Mg(1)Al12 cuboctahedra, and faces with twelve equivalent Al(1)Mg4Al8 cuboctahedra. Al(1) is bonded to four equivalent Mg(1) and eight equivalent Al(1) atoms to form distorted AlMg4Al8 cuboctahedra that share corners with four equivalent Mg(1)Al12 cuboctahedra, corners with fourteen equivalent Al(1)Mg4Al8 cuboctahedra, edges with six equivalent Mg(1)Al12 cuboctahedra, edges with twelve equivalent Al(1)Mg4Al8 cuboctahedra, faces with four equivalent Mg(1)Al12 cuboctahedra, and faces with sixteen equivalent Al(1)Mg4Al8 cuboctahedra. is represented by the CIF card [CIF]
data_MgAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.849
_cell_length_b   5.849
_cell_length_c   4.666
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   138.237
_cell_formula_units_Z   2
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  0.667  0.333  0.250  1.0
  Mg  Mg1  1  0.333  0.667  0.750  1.0
  Al  Al2  1  0.161  0.322  0.250  1.0
  Al  Al3  1  0.678  0.839  0.250  1.0
  Al  Al4  1  0.161  0.839  0.250  1.0
  Al  Al5  1  0.322  0.161  0.750  1.0
  Al  Al6  1  0.839  0.161  0.750  1.0
  Al  Al7  1  0.839  0.678  0.750  1.0
[/CIF]
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