The crystal structure described by MgSi2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent Mg(1), two equivalent Si(2), three equivalent Si(1), and five equivalent Si(3) atoms to form a mixture of distorted corner, face, and edge-sharing MgMg2Si10 cuboctahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 6-coordinate geometry to six equivalent Mg(1) and two equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to four equivalent Mg(1), two equivalent Si(1), and four equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 5-coordinate geometry to five equivalent Mg(1) and two equivalent Si(2) atoms. is represented by the CIF file [CIF]
data_MgSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.973
_cell_length_b   4.973
_cell_length_c   5.734
_cell_angle_alpha   76.955
_cell_angle_beta   76.955
_cell_angle_gamma   46.333
_symmetry_Int_Tables_number   1
_cell_volume   99.443
_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  0.836  0.836  0.824  1.0
  Mg  Mg1  1  0.164  0.164  0.176  1.0
  Si  Si2  1  0.500  0.500  0.000  1.0
  Si  Si3  1  0.500  0.500  0.500  1.0
  Si  Si4  1  0.845  0.845  0.334  1.0
  Si  Si5  1  0.155  0.155  0.666  1.0
[/CIF]
.
The crystal structure described by MgSi2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent Mg(1), two equivalent Si(2), three equivalent Si(1), and five equivalent Si(3) atoms to form a mixture of distorted corner, face, and edge-sharing MgMg2Si10 cuboctahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 6-coordinate geometry to six equivalent Mg(1) and two equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to four equivalent Mg(1), two equivalent Si(1), and four equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 5-coordinate geometry to five equivalent Mg(1) and two equivalent Si(2) atoms. is represented by the CIF file [CIF]
data_MgSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.973
_cell_length_b   4.973
_cell_length_c   5.734
_cell_angle_alpha   76.955
_cell_angle_beta   76.955
_cell_angle_gamma   46.333
_symmetry_Int_Tables_number   1
_cell_volume   99.443
_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  0.836  0.836  0.824  1.0
  Mg  Mg1  1  0.164  0.164  0.176  1.0
  Si  Si2  1  0.500  0.500  0.000  1.0
  Si  Si3  1  0.500  0.500  0.500  1.0
  Si  Si4  1  0.845  0.845  0.334  1.0
  Si  Si5  1  0.155  0.155  0.666  1.0
[/CIF]
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