The compound described by MgSi crystallizes in the monoclinic C2/m space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one Si(1) and three equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 5-coordinate geometry to one Si(3), three equivalent Si(1), and three equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(2), 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 two equivalent Mg(3), three equivalent Mg(2), one Si(2), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 7-coordinate geometry to one Mg(2), two equivalent Mg(3), three equivalent Mg(1), and one Si(3) atom. is represented by the CIF card [CIF]
data_MgSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.878
_cell_length_b   5.878
_cell_length_c   10.479
_cell_angle_alpha   75.291
_cell_angle_beta   75.291
_cell_angle_gamma   40.475
_symmetry_Int_Tables_number   1
_cell_volume   226.238
_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  0.821  0.821  0.089  1.0
  Mg  Mg1  1  0.179  0.179  0.911  1.0
  Mg  Mg2  1  0.627  0.627  0.688  1.0
  Mg  Mg3  1  0.373  0.373  0.312  1.0
  Mg  Mg4  1  0.903  0.903  0.759  1.0
  Mg  Mg5  1  0.097  0.097  0.241  1.0
  Si  Si6  1  0.691  0.691  0.382  1.0
  Si  Si7  1  0.890  0.890  0.481  1.0
  Si  Si8  1  0.554  0.554  0.082  1.0
  Si  Si9  1  0.446  0.446  0.918  1.0
  Si  Si10  1  0.309  0.309  0.618  1.0
  Si  Si11  1  0.110  0.110  0.519  1.0
[/CIF]
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The compound described by MgSi crystallizes in the monoclinic C2/m space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one Si(1) and three equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 5-coordinate geometry to one Si(3), three equivalent Si(1), and three equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(2), 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 two equivalent Mg(3), three equivalent Mg(2), one Si(2), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 7-coordinate geometry to one Mg(2), two equivalent Mg(3), three equivalent Mg(1), and one Si(3) atom. is represented by the CIF card [CIF]
data_MgSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.878
_cell_length_b   5.878
_cell_length_c   10.479
_cell_angle_alpha   75.291
_cell_angle_beta   75.291
_cell_angle_gamma   40.475
_symmetry_Int_Tables_number   1
_cell_volume   226.238
_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  0.821  0.821  0.089  1.0
  Mg  Mg1  1  0.179  0.179  0.911  1.0
  Mg  Mg2  1  0.627  0.627  0.688  1.0
  Mg  Mg3  1  0.373  0.373  0.312  1.0
  Mg  Mg4  1  0.903  0.903  0.759  1.0
  Mg  Mg5  1  0.097  0.097  0.241  1.0
  Si  Si6  1  0.691  0.691  0.382  1.0
  Si  Si7  1  0.890  0.890  0.481  1.0
  Si  Si8  1  0.554  0.554  0.082  1.0
  Si  Si9  1  0.446  0.446  0.918  1.0
  Si  Si10  1  0.309  0.309  0.618  1.0
  Si  Si11  1  0.110  0.110  0.519  1.0
[/CIF]
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