The compound described by Mg5Ga crystallizes in the hexagonal P-6m2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Ga(1) atoms to form distorted MgMg9Ga3 cuboctahedra that share corners with six equivalent Mg(3)Mg12 cuboctahedra, corners with twelve equivalent Mg(1)Mg9Ga3 cuboctahedra, edges with six equivalent Mg(2)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg9Ga3 cuboctahedra,  a faceface with one Mg(3)Mg12 cuboctahedra, faces with six equivalent Mg(2)Mg12 cuboctahedra, and faces with seven equivalent Mg(1)Mg9Ga3 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Mg(1), three equivalent Mg(3), and six equivalent Mg(2) atoms to form MgMg12 cuboctahedra that share corners with twelve equivalent Mg(2)Mg12 cuboctahedra, edges with six equivalent Mg(2)Mg12 cuboctahedra, edges with six equivalent Mg(3)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg9Ga3 cuboctahedra, faces with six equivalent Mg(3)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg9Ga3 cuboctahedra, and faces with seven equivalent Mg(2)Mg12 cuboctahedra. In the third Mg site, Mg(3) is bonded to six equivalent Mg(2) and six equivalent Mg(3) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(3)Mg12 cuboctahedra, corners with twelve equivalent Mg(1)Mg9Ga3 cuboctahedra, edges with six equivalent Mg(3)Mg12 cuboctahedra, edges with twelve equivalent Mg(2)Mg12 cuboctahedra, faces with two equivalent Mg(1)Mg9Ga3 cuboctahedra, faces with six equivalent Mg(3)Mg12 cuboctahedra, and faces with twelve equivalent Mg(2)Mg12 cuboctahedra. Ga(1) is bonded in a 6-coordinate geometry to six equivalent Mg(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg5Ga
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.124
_cell_length_b   3.124
_cell_length_c   15.622
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   132.072
_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  0.841  1.0
  Mg  Mg1  1  0.667  0.333  0.668  1.0
  Mg  Mg2  1  0.000  0.000  0.500  1.0
  Mg  Mg3  1  0.667  0.333  0.332  1.0
  Mg  Mg4  1  0.000  0.000  0.159  1.0
  Ga  Ga5  1  0.667  0.333  0.000  1.0
[/CIF]
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The compound described by Mg5Ga crystallizes in the hexagonal P-6m2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Ga(1) atoms to form distorted MgMg9Ga3 cuboctahedra that share corners with six equivalent Mg(3)Mg12 cuboctahedra, corners with twelve equivalent Mg(1)Mg9Ga3 cuboctahedra, edges with six equivalent Mg(2)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg9Ga3 cuboctahedra,  a faceface with one Mg(3)Mg12 cuboctahedra, faces with six equivalent Mg(2)Mg12 cuboctahedra, and faces with seven equivalent Mg(1)Mg9Ga3 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Mg(1), three equivalent Mg(3), and six equivalent Mg(2) atoms to form MgMg12 cuboctahedra that share corners with twelve equivalent Mg(2)Mg12 cuboctahedra, edges with six equivalent Mg(2)Mg12 cuboctahedra, edges with six equivalent Mg(3)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg9Ga3 cuboctahedra, faces with six equivalent Mg(3)Mg12 cuboctahedra, faces with six equivalent Mg(1)Mg9Ga3 cuboctahedra, and faces with seven equivalent Mg(2)Mg12 cuboctahedra. In the third Mg site, Mg(3) is bonded to six equivalent Mg(2) and six equivalent Mg(3) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(3)Mg12 cuboctahedra, corners with twelve equivalent Mg(1)Mg9Ga3 cuboctahedra, edges with six equivalent Mg(3)Mg12 cuboctahedra, edges with twelve equivalent Mg(2)Mg12 cuboctahedra, faces with two equivalent Mg(1)Mg9Ga3 cuboctahedra, faces with six equivalent Mg(3)Mg12 cuboctahedra, and faces with twelve equivalent Mg(2)Mg12 cuboctahedra. Ga(1) is bonded in a 6-coordinate geometry to six equivalent Mg(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg5Ga
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.124
_cell_length_b   3.124
_cell_length_c   15.622
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   132.072
_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  0.841  1.0
  Mg  Mg1  1  0.667  0.333  0.668  1.0
  Mg  Mg2  1  0.000  0.000  0.500  1.0
  Mg  Mg3  1  0.667  0.333  0.332  1.0
  Mg  Mg4  1  0.000  0.000  0.159  1.0
  Ga  Ga5  1  0.667  0.333  0.000  1.0
[/CIF]
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