The compound 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 7-coordinate geometry to three equivalent Mg(3), two equivalent Si(2), two equivalent Si(3), and three equivalent Si(1) atoms. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to one Mg(3), two equivalent Si(1), two equivalent Si(3), and four equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 12-coordinate geometry to one Mg(2), one Mg(3), three equivalent Mg(1), two equivalent Si(1), two equivalent Si(2), and three 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 two equivalent Mg(2), two equivalent Mg(3), three equivalent Mg(1), one Si(1), and one Si(3) atom. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), four equivalent Mg(2), one Si(2), and one Si(3) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), three equivalent Mg(3), one Si(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_MgSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.519
_cell_length_b   5.695
_cell_length_c   7.629
_cell_angle_alpha   96.646
_cell_angle_beta   95.197
_cell_angle_gamma   111.427
_symmetry_Int_Tables_number   1
_cell_volume   219.428
_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  0.402  0.975  0.686  1.0
  Mg  Mg1  1  0.737  0.796  0.977  1.0
  Mg  Mg2  1  0.598  0.025  0.314  1.0
  Mg  Mg3  1  0.189  0.483  0.357  1.0
  Mg  Mg4  1  0.263  0.204  0.023  1.0
  Mg  Mg5  1  0.811  0.517  0.643  1.0
  Si  Si6  1  0.922  0.055  0.640  1.0
  Si  Si7  1  0.802  0.316  0.013  1.0
  Si  Si8  1  0.198  0.684  0.987  1.0
  Si  Si9  1  0.300  0.463  0.720  1.0
  Si  Si10  1  0.078  0.945  0.360  1.0
  Si  Si11  1  0.700  0.537  0.280  1.0
[/CIF]
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The compound 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 7-coordinate geometry to three equivalent Mg(3), two equivalent Si(2), two equivalent Si(3), and three equivalent Si(1) atoms. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to one Mg(3), two equivalent Si(1), two equivalent Si(3), and four equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 12-coordinate geometry to one Mg(2), one Mg(3), three equivalent Mg(1), two equivalent Si(1), two equivalent Si(2), and three 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 two equivalent Mg(2), two equivalent Mg(3), three equivalent Mg(1), one Si(1), and one Si(3) atom. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), four equivalent Mg(2), one Si(2), and one Si(3) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), three equivalent Mg(3), one Si(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_MgSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.519
_cell_length_b   5.695
_cell_length_c   7.629
_cell_angle_alpha   96.646
_cell_angle_beta   95.197
_cell_angle_gamma   111.427
_symmetry_Int_Tables_number   1
_cell_volume   219.428
_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  0.402  0.975  0.686  1.0
  Mg  Mg1  1  0.737  0.796  0.977  1.0
  Mg  Mg2  1  0.598  0.025  0.314  1.0
  Mg  Mg3  1  0.189  0.483  0.357  1.0
  Mg  Mg4  1  0.263  0.204  0.023  1.0
  Mg  Mg5  1  0.811  0.517  0.643  1.0
  Si  Si6  1  0.922  0.055  0.640  1.0
  Si  Si7  1  0.802  0.316  0.013  1.0
  Si  Si8  1  0.198  0.684  0.987  1.0
  Si  Si9  1  0.300  0.463  0.720  1.0
  Si  Si10  1  0.078  0.945  0.360  1.0
  Si  Si11  1  0.700  0.537  0.280  1.0
[/CIF]
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