The crystal structure described by MgSi crystallizes in the triclinic P-1 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 5-coordinate geometry to one Si(1) and five equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to one Si(3), three equivalent Si(1), and four equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to one Si(2), two equivalent Si(1), and two equivalent Si(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Mg(1), two equivalent Mg(3), three equivalent Mg(2), and three equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(2), one Si(2), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Mg(2), two equivalent Mg(3), five equivalent Mg(1), and one Si(3) atom. is represented by the CIF file [CIF]
data_MgSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.462
_cell_length_b   5.264
_cell_length_c   10.360
_cell_angle_alpha   91.689
_cell_angle_beta   92.149
_cell_angle_gamma   113.505
_symmetry_Int_Tables_number   1
_cell_volume   222.744
_cell_formula_units_Z   6
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  0.879  0.733  0.902  1.0
  Mg  Mg1  1  0.121  0.267  0.098  1.0
  Mg  Mg2  1  0.545  0.105  0.349  1.0
  Mg  Mg3  1  0.455  0.895  0.651  1.0
  Mg  Mg4  1  0.818  0.659  0.204  1.0
  Mg  Mg5  1  0.182  0.341  0.796  1.0
  Si  Si6  1  0.749  0.490  0.643  1.0
  Si  Si7  1  0.871  0.763  0.460  1.0
  Si  Si8  1  0.592  0.138  0.907  1.0
  Si  Si9  1  0.408  0.862  0.093  1.0
  Si  Si10  1  0.251  0.510  0.357  1.0
  Si  Si11  1  0.129  0.237  0.540  1.0
[/CIF]
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The crystal structure described by MgSi crystallizes in the triclinic P-1 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 5-coordinate geometry to one Si(1) and five equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to one Si(3), three equivalent Si(1), and four equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to one Si(2), two equivalent Si(1), and two equivalent Si(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Mg(1), two equivalent Mg(3), three equivalent Mg(2), and three equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(2), one Si(2), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Mg(2), two equivalent Mg(3), five equivalent Mg(1), and one Si(3) atom. is represented by the CIF file [CIF]
data_MgSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.462
_cell_length_b   5.264
_cell_length_c   10.360
_cell_angle_alpha   91.689
_cell_angle_beta   92.149
_cell_angle_gamma   113.505
_symmetry_Int_Tables_number   1
_cell_volume   222.744
_cell_formula_units_Z   6
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  0.879  0.733  0.902  1.0
  Mg  Mg1  1  0.121  0.267  0.098  1.0
  Mg  Mg2  1  0.545  0.105  0.349  1.0
  Mg  Mg3  1  0.455  0.895  0.651  1.0
  Mg  Mg4  1  0.818  0.659  0.204  1.0
  Mg  Mg5  1  0.182  0.341  0.796  1.0
  Si  Si6  1  0.749  0.490  0.643  1.0
  Si  Si7  1  0.871  0.763  0.460  1.0
  Si  Si8  1  0.592  0.138  0.907  1.0
  Si  Si9  1  0.408  0.862  0.093  1.0
  Si  Si10  1  0.251  0.510  0.357  1.0
  Si  Si11  1  0.129  0.237  0.540  1.0
[/CIF]
.