The compound described by Mg2Si is Cubic Laves structured and crystallizes in the cubic Fd-3m space group. Mg(1) is bonded to six equivalent Mg(1) and six equivalent Si(1) atoms to form a mixture of distorted corner, edge, and face-sharing MgMg6Si6 cuboctahedra. Si(1) is bonded in a 12-coordinate geometry to twelve equivalent Mg(1) atoms. is represented by the CIF card [CIF]
data_Mg2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.589
_cell_length_b   5.589
_cell_length_c   5.589
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   123.417
_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  0.375  0.875  0.875  1.0
  Mg  Mg1  1  0.875  0.375  0.875  1.0
  Mg  Mg2  1  0.875  0.875  0.875  1.0
  Mg  Mg3  1  0.875  0.875  0.375  1.0
  Si  Si4  1  0.500  0.500  0.500  1.0
  Si  Si5  1  0.250  0.250  0.250  1.0
[/CIF]
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The compound described by Mg2Si is Cubic Laves structured and crystallizes in the cubic Fd-3m space group. Mg(1) is bonded to six equivalent Mg(1) and six equivalent Si(1) atoms to form a mixture of distorted corner, edge, and face-sharing MgMg6Si6 cuboctahedra. Si(1) is bonded in a 12-coordinate geometry to twelve equivalent Mg(1) atoms. is represented by the CIF card [CIF]
data_Mg2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.589
_cell_length_b   5.589
_cell_length_c   5.589
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   123.417
_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  0.375  0.875  0.875  1.0
  Mg  Mg1  1  0.875  0.375  0.875  1.0
  Mg  Mg2  1  0.875  0.875  0.875  1.0
  Mg  Mg3  1  0.875  0.875  0.375  1.0
  Si  Si4  1  0.500  0.500  0.500  1.0
  Si  Si5  1  0.250  0.250  0.250  1.0
[/CIF]
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