The structure described by Mg3Au13 crystallizes in the tetragonal P4mm space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Au(1), four equivalent Au(6), and four equivalent Au(8) atoms to form a mixture of corner, edge, and face-sharing MgAu12 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Au(1), four equivalent Au(3), and four equivalent Au(7) atoms to form MgAu12 cuboctahedra that share corners with four equivalent Mg(1)Au12 cuboctahedra, corners with four equivalent Mg(2)Au12 cuboctahedra, corners with four equivalent Au(5)Au12 cuboctahedra, edges with four equivalent Au(9)Au12 cuboctahedra,  a faceface with one Mg(1)Au12 cuboctahedra,  a faceface with one Au(5)Au12 cuboctahedra, and faces with four equivalent Mg(2)Au12 cuboctahedra. In the third Mg site, Mg(3) is bonded to four equivalent Au(2), four equivalent Au(4), and four equivalent Au(8) atoms to form MgAu12 cuboctahedra that share corners with four equivalent Mg(3)Au12 cuboctahedra, corners with four equivalent Au(9)Au12 cuboctahedra, edges with four equivalent Mg(1)Au12 cuboctahedra, edges with four equivalent Au(5)Au12 cuboctahedra,  a faceface with one Au(9)Au12 cuboctahedra, and faces with four equivalent Mg(3)Au12 cuboctahedra. There are nine inequivalent Au sites. In the first Au site, Au(1) is bonded in a distorted square co-planar geometry to two equivalent Mg(1) and two equivalent Mg(2) atoms. In the second Au site, Au(2) is bonded in a distorted L-shaped geometry to two equivalent Mg(3), two equivalent Au(5), and two equivalent Au(9) atoms. In the third Au site, Au(3) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Mg(2) atoms. In the fourth Au site, Au(4) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Mg(3) atoms. In the fifth Au site, Au(5) is bonded to four equivalent Au(2), four equivalent Au(7), and four equivalent Au(9) atoms to form AuAu12 cuboctahedra that share corners with four equivalent Mg(2)Au12 cuboctahedra, corners with four equivalent Au(5)Au12 cuboctahedra, edges with four equivalent Mg(3)Au12 cuboctahedra,  a faceface with one Mg(2)Au12 cuboctahedra, faces with four equivalent Au(5)Au12 cuboctahedra, and faces with four equivalent Au(9)Au12 cuboctahedra. In the sixth Au site, Au(6) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Mg(1) atoms. In the seventh Au site, Au(7) is bonded in a distorted L-shaped geometry to two equivalent Mg(2), two equivalent Au(5), and two equivalent Au(9) atoms. In the eighth Au site, Au(8) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Mg(3) atoms. In the ninth Au site, Au(9) is bonded to four equivalent Au(2), four equivalent Au(5), and four equivalent Au(7) atoms to form AuAu12 cuboctahedra that share corners with four equivalent Mg(3)Au12 cuboctahedra, corners with four equivalent Au(9)Au12 cuboctahedra, edges with four equivalent Mg(2)Au12 cuboctahedra,  a faceface with one Mg(3)Au12 cuboctahedra, faces with four equivalent Au(5)Au12 cuboctahedra, and faces with four equivalent Au(9)Au12 cuboctahedra. is represented by the CIF card [CIF]
data_Mg3Au13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.078
_cell_length_b   4.078
_cell_length_c   16.697
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   277.687
_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  0.872  1.0
  Mg  Mg1  1  0.000  0.000  0.126  1.0
  Mg  Mg2  1  0.500  0.500  0.625  1.0
  Au  Au3  1  0.500  0.000  0.000  1.0
  Au  Au4  1  0.000  0.500  0.503  1.0
  Au  Au5  1  0.500  0.000  0.503  1.0
  Au  Au6  1  0.000  0.500  0.000  1.0
  Au  Au7  1  0.500  0.500  0.124  1.0
  Au  Au8  1  0.000  0.000  0.625  1.0
  Au  Au9  1  0.000  0.000  0.378  1.0
  Au  Au10  1  0.500  0.500  0.877  1.0
  Au  Au11  1  0.000  0.500  0.247  1.0
  Au  Au12  1  0.500  0.000  0.750  1.0
  Au  Au13  1  0.500  0.000  0.247  1.0
  Au  Au14  1  0.000  0.500  0.750  1.0
  Au  Au15  1  0.500  0.500  0.372  1.0
[/CIF]
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The structure described by Mg3Au13 crystallizes in the tetragonal P4mm space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Au(1), four equivalent Au(6), and four equivalent Au(8) atoms to form a mixture of corner, edge, and face-sharing MgAu12 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Au(1), four equivalent Au(3), and four equivalent Au(7) atoms to form MgAu12 cuboctahedra that share corners with four equivalent Mg(1)Au12 cuboctahedra, corners with four equivalent Mg(2)Au12 cuboctahedra, corners with four equivalent Au(5)Au12 cuboctahedra, edges with four equivalent Au(9)Au12 cuboctahedra,  a faceface with one Mg(1)Au12 cuboctahedra,  a faceface with one Au(5)Au12 cuboctahedra, and faces with four equivalent Mg(2)Au12 cuboctahedra. In the third Mg site, Mg(3) is bonded to four equivalent Au(2), four equivalent Au(4), and four equivalent Au(8) atoms to form MgAu12 cuboctahedra that share corners with four equivalent Mg(3)Au12 cuboctahedra, corners with four equivalent Au(9)Au12 cuboctahedra, edges with four equivalent Mg(1)Au12 cuboctahedra, edges with four equivalent Au(5)Au12 cuboctahedra,  a faceface with one Au(9)Au12 cuboctahedra, and faces with four equivalent Mg(3)Au12 cuboctahedra. There are nine inequivalent Au sites. In the first Au site, Au(1) is bonded in a distorted square co-planar geometry to two equivalent Mg(1) and two equivalent Mg(2) atoms. In the second Au site, Au(2) is bonded in a distorted L-shaped geometry to two equivalent Mg(3), two equivalent Au(5), and two equivalent Au(9) atoms. In the third Au site, Au(3) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Mg(2) atoms. In the fourth Au site, Au(4) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Mg(3) atoms. In the fifth Au site, Au(5) is bonded to four equivalent Au(2), four equivalent Au(7), and four equivalent Au(9) atoms to form AuAu12 cuboctahedra that share corners with four equivalent Mg(2)Au12 cuboctahedra, corners with four equivalent Au(5)Au12 cuboctahedra, edges with four equivalent Mg(3)Au12 cuboctahedra,  a faceface with one Mg(2)Au12 cuboctahedra, faces with four equivalent Au(5)Au12 cuboctahedra, and faces with four equivalent Au(9)Au12 cuboctahedra. In the sixth Au site, Au(6) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Mg(1) atoms. In the seventh Au site, Au(7) is bonded in a distorted L-shaped geometry to two equivalent Mg(2), two equivalent Au(5), and two equivalent Au(9) atoms. In the eighth Au site, Au(8) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Mg(3) atoms. In the ninth Au site, Au(9) is bonded to four equivalent Au(2), four equivalent Au(5), and four equivalent Au(7) atoms to form AuAu12 cuboctahedra that share corners with four equivalent Mg(3)Au12 cuboctahedra, corners with four equivalent Au(9)Au12 cuboctahedra, edges with four equivalent Mg(2)Au12 cuboctahedra,  a faceface with one Mg(3)Au12 cuboctahedra, faces with four equivalent Au(5)Au12 cuboctahedra, and faces with four equivalent Au(9)Au12 cuboctahedra. is represented by the CIF card [CIF]
data_Mg3Au13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.078
_cell_length_b   4.078
_cell_length_c   16.697
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   277.687
_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  0.872  1.0
  Mg  Mg1  1  0.000  0.000  0.126  1.0
  Mg  Mg2  1  0.500  0.500  0.625  1.0
  Au  Au3  1  0.500  0.000  0.000  1.0
  Au  Au4  1  0.000  0.500  0.503  1.0
  Au  Au5  1  0.500  0.000  0.503  1.0
  Au  Au6  1  0.000  0.500  0.000  1.0
  Au  Au7  1  0.500  0.500  0.124  1.0
  Au  Au8  1  0.000  0.000  0.625  1.0
  Au  Au9  1  0.000  0.000  0.378  1.0
  Au  Au10  1  0.500  0.500  0.877  1.0
  Au  Au11  1  0.000  0.500  0.247  1.0
  Au  Au12  1  0.500  0.000  0.750  1.0
  Au  Au13  1  0.500  0.000  0.247  1.0
  Au  Au14  1  0.000  0.500  0.750  1.0
  Au  Au15  1  0.500  0.500  0.372  1.0
[/CIF]
.