The structure described by La2Mg crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded in a 10-coordinate geometry to four equivalent La(2) and six equivalent La(1) atoms. There are two inequivalent La sites. In the first La site, La(1) is bonded to six equivalent Mg(1), two equivalent La(2), and four equivalent La(1) atoms to form LaLa6Mg6 cuboctahedra that share corners with six equivalent La(1)La6Mg6 cuboctahedra, corners with six equivalent La(2)La8Mg4 cuboctahedra, edges with eleven equivalent La(2)La8Mg4 cuboctahedra, faces with four equivalent La(2)La8Mg4 cuboctahedra, and faces with ten equivalent La(1)La6Mg6 cuboctahedra. In the second La site, La(2) is bonded to four equivalent Mg(1), two equivalent La(1), and six equivalent La(2) atoms to form LaLa8Mg4 cuboctahedra that share corners with six equivalent La(1)La6Mg6 cuboctahedra, corners with six equivalent La(2)La8Mg4 cuboctahedra, edges with four equivalent La(2)La8Mg4 cuboctahedra, edges with eleven equivalent La(1)La6Mg6 cuboctahedra, faces with four equivalent La(1)La6Mg6 cuboctahedra, and faces with eight equivalent La(2)La8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_La2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.452
_cell_length_b   9.452
_cell_length_c   5.750
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   157.763
_symmetry_Int_Tables_number   1
_cell_volume   194.382
_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
  La  La0  1  0.444  0.556  0.250  1.0
  La  La1  1  0.775  0.225  0.250  1.0
  La  La2  1  0.225  0.775  0.750  1.0
  La  La3  1  0.556  0.444  0.750  1.0
  Mg  Mg4  1  0.111  0.889  0.250  1.0
  Mg  Mg5  1  0.889  0.111  0.750  1.0
[/CIF]
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The structure described by La2Mg crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded in a 10-coordinate geometry to four equivalent La(2) and six equivalent La(1) atoms. There are two inequivalent La sites. In the first La site, La(1) is bonded to six equivalent Mg(1), two equivalent La(2), and four equivalent La(1) atoms to form LaLa6Mg6 cuboctahedra that share corners with six equivalent La(1)La6Mg6 cuboctahedra, corners with six equivalent La(2)La8Mg4 cuboctahedra, edges with eleven equivalent La(2)La8Mg4 cuboctahedra, faces with four equivalent La(2)La8Mg4 cuboctahedra, and faces with ten equivalent La(1)La6Mg6 cuboctahedra. In the second La site, La(2) is bonded to four equivalent Mg(1), two equivalent La(1), and six equivalent La(2) atoms to form LaLa8Mg4 cuboctahedra that share corners with six equivalent La(1)La6Mg6 cuboctahedra, corners with six equivalent La(2)La8Mg4 cuboctahedra, edges with four equivalent La(2)La8Mg4 cuboctahedra, edges with eleven equivalent La(1)La6Mg6 cuboctahedra, faces with four equivalent La(1)La6Mg6 cuboctahedra, and faces with eight equivalent La(2)La8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_La2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.452
_cell_length_b   9.452
_cell_length_c   5.750
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   157.763
_symmetry_Int_Tables_number   1
_cell_volume   194.382
_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
  La  La0  1  0.444  0.556  0.250  1.0
  La  La1  1  0.775  0.225  0.250  1.0
  La  La2  1  0.225  0.775  0.750  1.0
  La  La3  1  0.556  0.444  0.750  1.0
  Mg  Mg4  1  0.111  0.889  0.250  1.0
  Mg  Mg5  1  0.889  0.111  0.750  1.0
[/CIF]
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