The crystal structure described by Mg3Li is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. Li(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form LiMg12 cuboctahedra that share corners with four equivalent Li(1)Mg12 cuboctahedra, corners with eight equivalent Mg(1)Li4Mg8 cuboctahedra, edges with eight equivalent Li(1)Mg12 cuboctahedra, edges with sixteen equivalent Mg(2)Li4Mg8 cuboctahedra, faces with four equivalent Li(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Li4Mg8 cuboctahedra, and faces with eight equivalent Mg(2)Li4Mg8 cuboctahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Li(1) and eight equivalent Mg(2) atoms to form MgLi4Mg8 cuboctahedra that share corners with four equivalent Mg(1)Li4Mg8 cuboctahedra, corners with eight equivalent Li(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Li4Mg8 cuboctahedra, edges with sixteen equivalent Mg(2)Li4Mg8 cuboctahedra, faces with four equivalent Mg(1)Li4Mg8 cuboctahedra, faces with six equivalent Li(1)Mg12 cuboctahedra, and faces with eight equivalent Mg(2)Li4Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Li(1), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted MgLi4Mg8 cuboctahedra that share corners with twelve equivalent Mg(2)Li4Mg8 cuboctahedra, edges with eight equivalent Li(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Li4Mg8 cuboctahedra, edges with eight equivalent Mg(2)Li4Mg8 cuboctahedra, faces with four equivalent Li(1)Mg12 cuboctahedra, faces with four equivalent Mg(1)Li4Mg8 cuboctahedra, and faces with ten equivalent Mg(2)Li4Mg8 cuboctahedra. is represented by the CIF file [CIF]
data_LiMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.323
_cell_length_b   5.323
_cell_length_c   5.323
_cell_angle_alpha   129.436
_cell_angle_beta   129.436
_cell_angle_gamma   74.310
_symmetry_Int_Tables_number   1
_cell_volume   87.684
_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
  Li  Li0  1  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.500  0.500  0.000  1.0
  Mg  Mg2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.750  0.250  0.500  1.0
[/CIF]
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The crystal structure described by Mg3Li is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. Li(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form LiMg12 cuboctahedra that share corners with four equivalent Li(1)Mg12 cuboctahedra, corners with eight equivalent Mg(1)Li4Mg8 cuboctahedra, edges with eight equivalent Li(1)Mg12 cuboctahedra, edges with sixteen equivalent Mg(2)Li4Mg8 cuboctahedra, faces with four equivalent Li(1)Mg12 cuboctahedra, faces with six equivalent Mg(1)Li4Mg8 cuboctahedra, and faces with eight equivalent Mg(2)Li4Mg8 cuboctahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Li(1) and eight equivalent Mg(2) atoms to form MgLi4Mg8 cuboctahedra that share corners with four equivalent Mg(1)Li4Mg8 cuboctahedra, corners with eight equivalent Li(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Li4Mg8 cuboctahedra, edges with sixteen equivalent Mg(2)Li4Mg8 cuboctahedra, faces with four equivalent Mg(1)Li4Mg8 cuboctahedra, faces with six equivalent Li(1)Mg12 cuboctahedra, and faces with eight equivalent Mg(2)Li4Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Li(1), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted MgLi4Mg8 cuboctahedra that share corners with twelve equivalent Mg(2)Li4Mg8 cuboctahedra, edges with eight equivalent Li(1)Mg12 cuboctahedra, edges with eight equivalent Mg(1)Li4Mg8 cuboctahedra, edges with eight equivalent Mg(2)Li4Mg8 cuboctahedra, faces with four equivalent Li(1)Mg12 cuboctahedra, faces with four equivalent Mg(1)Li4Mg8 cuboctahedra, and faces with ten equivalent Mg(2)Li4Mg8 cuboctahedra. is represented by the CIF file [CIF]
data_LiMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.323
_cell_length_b   5.323
_cell_length_c   5.323
_cell_angle_alpha   129.436
_cell_angle_beta   129.436
_cell_angle_gamma   74.310
_symmetry_Int_Tables_number   1
_cell_volume   87.684
_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
  Li  Li0  1  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.500  0.500  0.000  1.0
  Mg  Mg2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.750  0.250  0.500  1.0
[/CIF]
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