The material described by MgGa2 crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to six equivalent Mg(1), three equivalent Ga(2), and three equivalent Ga(3) atoms to form distorted MgMg6Ga6 cuboctahedra that share corners with six equivalent Ga(1)Ga12 cuboctahedra; corners with six equivalent Ga(2)Mg3Ga3 cuboctahedra; corners with six equivalent Ga(3)Mg6 cuboctahedra; corners with twelve Mg(1,1)Mg6Ga6 cuboctahedra; edges with six equivalent Mg(1)Mg6Ga6 cuboctahedra; edges with six equivalent Ga(2)Mg3Ga3 cuboctahedra; edges with six equivalent Ga(3)Mg6 cuboctahedra;  a faceface with one Ga(1)Ga12 cuboctahedra; and faces with seven Mg(1,1)Mg6Ga6 cuboctahedra. In the second Mg site, Mg(1) is bonded to six equivalent Mg(1), three equivalent Ga(2), and three equivalent Ga(3) atoms to form distorted MgMg6Ga6 cuboctahedra that share corners with six equivalent Ga(1)Ga12 cuboctahedra; corners with six equivalent Ga(2)Mg3Ga3 cuboctahedra; corners with six equivalent Ga(3)Mg6 cuboctahedra; corners with twelve Mg(1,1)Mg6Ga6 cuboctahedra; edges with six equivalent Mg(1)Mg6Ga6 cuboctahedra; edges with six equivalent Ga(2)Mg3Ga3 cuboctahedra; edges with six equivalent Ga(3)Mg6 cuboctahedra;  a faceface with one Ga(1)Ga12 cuboctahedra; and faces with seven Mg(1,1)Mg6Ga6 cuboctahedra. There are three inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to six equivalent Ga(1) and six equivalent Ga(2) atoms to form GaGa12 cuboctahedra that share corners with six equivalent Ga(1)Ga12 cuboctahedra; corners with twelve Mg(1,1)Mg6Ga6 cuboctahedra; corners with twelve equivalent Ga(2)Mg3Ga3 cuboctahedra; edges with six equivalent Ga(1)Ga12 cuboctahedra; edges with twelve equivalent Ga(2)Mg3Ga3 cuboctahedra; faces with two Mg(1,1)Mg6Ga6 cuboctahedra; and faces with six equivalent Ga(1)Ga12 cuboctahedra. In the second Ga site, Ga(2) is bonded to three equivalent Mg(1) and three equivalent Ga(1) atoms to form distorted GaMg3Ga3 cuboctahedra that share corners with six equivalent Mg(1)Mg6Ga6 cuboctahedra, corners with six equivalent Ga(1)Ga12 cuboctahedra, corners with six equivalent Ga(2)Mg3Ga3 cuboctahedra, corners with six equivalent Ga(3)Mg6 cuboctahedra, edges with six equivalent Mg(1)Mg6Ga6 cuboctahedra, edges with six equivalent Ga(1)Ga12 cuboctahedra, edges with six equivalent Ga(2)Mg3Ga3 cuboctahedra,  a faceface with one Ga(2)Mg3Ga3 cuboctahedra, and  a faceface with one Ga(3)Mg6 cuboctahedra. In the third Ga site, Ga(3) is bonded to six Mg(1,1) atoms to form distorted GaMg6 cuboctahedra that share corners with twelve Mg(1,1)Mg6Ga6 cuboctahedra; corners with twelve equivalent Ga(2)Mg3Ga3 cuboctahedra; edges with six equivalent Ga(3)Mg6 cuboctahedra; edges with twelve Mg(1,1)Mg6Ga6 cuboctahedra; and faces with two equivalent Ga(2)Mg3Ga3 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgGa2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.063
_cell_length_b   3.063
_cell_length_c   14.755
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   119.895
_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  0.000  0.000  0.167  1.0
  Mg  Mg1  1  0.000  0.000  0.834  1.0
  Ga  Ga2  1  0.000  0.000  0.500  1.0
  Ga  Ga3  1  0.667  0.333  0.330  1.0
  Ga  Ga4  1  0.667  0.333  0.000  1.0
  Ga  Ga5  1  0.667  0.333  0.670  1.0
[/CIF]
.
The material described by MgGa2 crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to six equivalent Mg(1), three equivalent Ga(2), and three equivalent Ga(3) atoms to form distorted MgMg6Ga6 cuboctahedra that share corners with six equivalent Ga(1)Ga12 cuboctahedra; corners with six equivalent Ga(2)Mg3Ga3 cuboctahedra; corners with six equivalent Ga(3)Mg6 cuboctahedra; corners with twelve Mg(1,1)Mg6Ga6 cuboctahedra; edges with six equivalent Mg(1)Mg6Ga6 cuboctahedra; edges with six equivalent Ga(2)Mg3Ga3 cuboctahedra; edges with six equivalent Ga(3)Mg6 cuboctahedra;  a faceface with one Ga(1)Ga12 cuboctahedra; and faces with seven Mg(1,1)Mg6Ga6 cuboctahedra. In the second Mg site, Mg(1) is bonded to six equivalent Mg(1), three equivalent Ga(2), and three equivalent Ga(3) atoms to form distorted MgMg6Ga6 cuboctahedra that share corners with six equivalent Ga(1)Ga12 cuboctahedra; corners with six equivalent Ga(2)Mg3Ga3 cuboctahedra; corners with six equivalent Ga(3)Mg6 cuboctahedra; corners with twelve Mg(1,1)Mg6Ga6 cuboctahedra; edges with six equivalent Mg(1)Mg6Ga6 cuboctahedra; edges with six equivalent Ga(2)Mg3Ga3 cuboctahedra; edges with six equivalent Ga(3)Mg6 cuboctahedra;  a faceface with one Ga(1)Ga12 cuboctahedra; and faces with seven Mg(1,1)Mg6Ga6 cuboctahedra. There are three inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to six equivalent Ga(1) and six equivalent Ga(2) atoms to form GaGa12 cuboctahedra that share corners with six equivalent Ga(1)Ga12 cuboctahedra; corners with twelve Mg(1,1)Mg6Ga6 cuboctahedra; corners with twelve equivalent Ga(2)Mg3Ga3 cuboctahedra; edges with six equivalent Ga(1)Ga12 cuboctahedra; edges with twelve equivalent Ga(2)Mg3Ga3 cuboctahedra; faces with two Mg(1,1)Mg6Ga6 cuboctahedra; and faces with six equivalent Ga(1)Ga12 cuboctahedra. In the second Ga site, Ga(2) is bonded to three equivalent Mg(1) and three equivalent Ga(1) atoms to form distorted GaMg3Ga3 cuboctahedra that share corners with six equivalent Mg(1)Mg6Ga6 cuboctahedra, corners with six equivalent Ga(1)Ga12 cuboctahedra, corners with six equivalent Ga(2)Mg3Ga3 cuboctahedra, corners with six equivalent Ga(3)Mg6 cuboctahedra, edges with six equivalent Mg(1)Mg6Ga6 cuboctahedra, edges with six equivalent Ga(1)Ga12 cuboctahedra, edges with six equivalent Ga(2)Mg3Ga3 cuboctahedra,  a faceface with one Ga(2)Mg3Ga3 cuboctahedra, and  a faceface with one Ga(3)Mg6 cuboctahedra. In the third Ga site, Ga(3) is bonded to six Mg(1,1) atoms to form distorted GaMg6 cuboctahedra that share corners with twelve Mg(1,1)Mg6Ga6 cuboctahedra; corners with twelve equivalent Ga(2)Mg3Ga3 cuboctahedra; edges with six equivalent Ga(3)Mg6 cuboctahedra; edges with twelve Mg(1,1)Mg6Ga6 cuboctahedra; and faces with two equivalent Ga(2)Mg3Ga3 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgGa2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.063
_cell_length_b   3.063
_cell_length_c   14.755
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   119.895
_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  0.000  0.000  0.167  1.0
  Mg  Mg1  1  0.000  0.000  0.834  1.0
  Ga  Ga2  1  0.000  0.000  0.500  1.0
  Ga  Ga3  1  0.667  0.333  0.330  1.0
  Ga  Ga4  1  0.667  0.333  0.000  1.0
  Ga  Ga5  1  0.667  0.333  0.670  1.0
[/CIF]
.