The material described by MgAl2 crystallizes in the tetragonal I4_1/amd space group. Mg(1) is bonded to two equivalent Mg(1), four equivalent Al(1), and six equivalent Al(2) atoms to form distorted MgMg2Al10 cuboctahedra that share corners with four equivalent Al(1)Mg4Al8 cuboctahedra, corners with eight equivalent Mg(1)Mg2Al10 cuboctahedra, edges with four equivalent Mg(1)Mg2Al10 cuboctahedra, edges with twelve equivalent Al(1)Mg4Al8 cuboctahedra, faces with five equivalent Al(1)Mg4Al8 cuboctahedra, and faces with seven equivalent Mg(1)Mg2Al10 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Mg(1), four equivalent Al(1), and four equivalent Al(2) atoms to form AlMg4Al8 cuboctahedra that share corners with four equivalent Mg(1)Mg2Al10 cuboctahedra, corners with four equivalent Al(1)Mg4Al8 cuboctahedra, edges with twelve equivalent Mg(1)Mg2Al10 cuboctahedra, faces with five equivalent Mg(1)Mg2Al10 cuboctahedra, and faces with eight equivalent Al(1)Mg4Al8 cuboctahedra. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to six equivalent Mg(1), two equivalent Al(2), and four equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgAl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.116
_cell_length_b   4.116
_cell_length_c   13.388
_cell_angle_alpha   98.842
_cell_angle_beta   98.842
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   221.373
_cell_formula_units_Z   4
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  0.332  0.832  0.663  1.0
  Mg  Mg1  1  0.918  0.918  0.837  1.0
  Mg  Mg2  1  0.168  0.668  0.337  1.0
  Mg  Mg3  1  0.082  0.082  0.163  1.0
  Al  Al4  1  0.500  0.000  0.001  1.0
  Al  Al5  1  0.750  0.750  0.499  1.0
  Al  Al6  1  1.000  0.500  0.999  1.0
  Al  Al7  1  0.250  0.250  0.501  1.0
  Al  Al8  1  0.670  0.170  0.339  1.0
  Al  Al9  1  0.580  0.580  0.161  1.0
  Al  Al10  1  0.830  0.330  0.661  1.0
  Al  Al11  1  0.420  0.420  0.839  1.0
[/CIF]
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The material described by MgAl2 crystallizes in the tetragonal I4_1/amd space group. Mg(1) is bonded to two equivalent Mg(1), four equivalent Al(1), and six equivalent Al(2) atoms to form distorted MgMg2Al10 cuboctahedra that share corners with four equivalent Al(1)Mg4Al8 cuboctahedra, corners with eight equivalent Mg(1)Mg2Al10 cuboctahedra, edges with four equivalent Mg(1)Mg2Al10 cuboctahedra, edges with twelve equivalent Al(1)Mg4Al8 cuboctahedra, faces with five equivalent Al(1)Mg4Al8 cuboctahedra, and faces with seven equivalent Mg(1)Mg2Al10 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Mg(1), four equivalent Al(1), and four equivalent Al(2) atoms to form AlMg4Al8 cuboctahedra that share corners with four equivalent Mg(1)Mg2Al10 cuboctahedra, corners with four equivalent Al(1)Mg4Al8 cuboctahedra, edges with twelve equivalent Mg(1)Mg2Al10 cuboctahedra, faces with five equivalent Mg(1)Mg2Al10 cuboctahedra, and faces with eight equivalent Al(1)Mg4Al8 cuboctahedra. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to six equivalent Mg(1), two equivalent Al(2), and four equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgAl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.116
_cell_length_b   4.116
_cell_length_c   13.388
_cell_angle_alpha   98.842
_cell_angle_beta   98.842
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   221.373
_cell_formula_units_Z   4
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  0.332  0.832  0.663  1.0
  Mg  Mg1  1  0.918  0.918  0.837  1.0
  Mg  Mg2  1  0.168  0.668  0.337  1.0
  Mg  Mg3  1  0.082  0.082  0.163  1.0
  Al  Al4  1  0.500  0.000  0.001  1.0
  Al  Al5  1  0.750  0.750  0.499  1.0
  Al  Al6  1  1.000  0.500  0.999  1.0
  Al  Al7  1  0.250  0.250  0.501  1.0
  Al  Al8  1  0.670  0.170  0.339  1.0
  Al  Al9  1  0.580  0.580  0.161  1.0
  Al  Al10  1  0.830  0.330  0.661  1.0
  Al  Al11  1  0.420  0.420  0.839  1.0
[/CIF]
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