data_MgAu3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.25
_cell_length_b   9.25
_cell_length_c   9.25
_cell_angle_alpha   18.93
_cell_angle_beta   18.93
_cell_angle_gamma   18.93
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgAu3
_chemical_formula_sum   'Mg1 Au3'
_cell_volume   72.74
_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  Mg3  1  0.0  0.0  0.0  1.0
  Au  Au0  1  0.0  0.0  0.3  1.0
  Au  Au1  1  0.0  0.0  0.62  1.0
  Au  Au2  1  0.0  0.0  0.94  1.0

data_MgAu3
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.27
_cell_length_b   3.04
_cell_length_c   9.25
_cell_angle_alpha   90.0
_cell_angle_beta   100.95
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   MgAu3
_chemical_formula_sum   'Mg2 Au6'
_cell_volume   145.49
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.0  0.0  0.0  1.0
  Au  Au1  2  0.0  0.0  0.06  1.0
  Au  Au2  2  0.0  0.0  0.7  1.0
  Au  Au3  2  0.0  0.0  0.38  1.0

Mg Au Au Au
MgAu3 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a single-bond geometry to one Au(1) and one Au(3) atom. The Mg(1)-Au(1) bond length is 2.80 Å. The Mg(1)-Au(3) bond length is 0.60 Å. There are four inequivalent Au sites. In the first Au site, Au(1) is bonded in a single-bond geometry to one Mg(1) and one Au(2) atom. The Au(1)-Au(2) bond length is 2.93 Å. In the second Au site, Au(2) is bonded to one Au(1); one Au(3); and six Au(2,2) atoms to form a mixture of corner and edge-sharing AuAu8 hexagonal bipyramids. The Au(2)-Au(3) bond length is 2.93 Å. All Au(2)-Au(2,2) bond lengths are 3.04 Å. In the third Au site, Au(3) is bonded in a single-bond geometry to one Mg(1) and one Au(2) atom. In the fourth Au site, Au(2) is bonded to one Au(1); one Au(3); and six Au(2,2) atoms to form a mixture of corner and edge-sharing AuAu8 hexagonal bipyramids. The Au(2)-Au(1) bond length is 2.93 Å. The Au(2)-Au(3) bond length is 2.93 Å. Both Au(2)-Au(2) bond lengths are 3.04 Å.