The compound described by Mg2Si crystallizes in the triclinic P-1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to one Si(1) and two equivalent Si(2) atoms. In the second Mg site, Mg(2) is bonded in a 5-coordinate geometry to two equivalent Si(2) and three equivalent Si(1) atoms. In the third Mg site, Mg(3) is bonded in a 4-coordinate geometry to two equivalent Si(1) and two equivalent Si(2) atoms. In the fourth Mg site, Mg(4) is bonded in a 3-coordinate geometry to one Si(1) and two equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to one Mg(1), one Mg(4), two equivalent Mg(3), three equivalent Mg(2), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. is represented by the CIF card [CIF]
data_Mg2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.392
_cell_length_b   6.359
_cell_length_c   7.735
_cell_angle_alpha   108.056
_cell_angle_beta   90.183
_cell_angle_gamma   98.804
_symmetry_Int_Tables_number   1
_cell_volume   248.852
_cell_formula_units_Z   4
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  0.797  0.898  0.602  1.0
  Mg  Mg1  1  0.051  0.753  0.971  1.0
  Mg  Mg2  1  0.522  0.661  0.197  1.0
  Mg  Mg3  1  0.281  0.635  0.580  1.0
  Mg  Mg4  1  0.478  0.339  0.803  1.0
  Mg  Mg5  1  0.719  0.365  0.420  1.0
  Mg  Mg6  1  0.203  0.102  0.398  1.0
  Mg  Mg7  1  0.949  0.247  0.029  1.0
  Si  Si8  1  0.576  0.835  0.902  1.0
  Si  Si9  1  0.424  0.165  0.098  1.0
  Si  Si10  1  0.022  0.667  0.296  1.0
  Si  Si11  1  0.978  0.333  0.704  1.0
[/CIF]
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The compound described by Mg2Si crystallizes in the triclinic P-1 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to one Si(1) and two equivalent Si(2) atoms. In the second Mg site, Mg(2) is bonded in a 5-coordinate geometry to two equivalent Si(2) and three equivalent Si(1) atoms. In the third Mg site, Mg(3) is bonded in a 4-coordinate geometry to two equivalent Si(1) and two equivalent Si(2) atoms. In the fourth Mg site, Mg(4) is bonded in a 3-coordinate geometry to one Si(1) and two equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to one Mg(1), one Mg(4), two equivalent Mg(3), three equivalent Mg(2), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. is represented by the CIF card [CIF]
data_Mg2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.392
_cell_length_b   6.359
_cell_length_c   7.735
_cell_angle_alpha   108.056
_cell_angle_beta   90.183
_cell_angle_gamma   98.804
_symmetry_Int_Tables_number   1
_cell_volume   248.852
_cell_formula_units_Z   4
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  0.797  0.898  0.602  1.0
  Mg  Mg1  1  0.051  0.753  0.971  1.0
  Mg  Mg2  1  0.522  0.661  0.197  1.0
  Mg  Mg3  1  0.281  0.635  0.580  1.0
  Mg  Mg4  1  0.478  0.339  0.803  1.0
  Mg  Mg5  1  0.719  0.365  0.420  1.0
  Mg  Mg6  1  0.203  0.102  0.398  1.0
  Mg  Mg7  1  0.949  0.247  0.029  1.0
  Si  Si8  1  0.576  0.835  0.902  1.0
  Si  Si9  1  0.424  0.165  0.098  1.0
  Si  Si10  1  0.022  0.667  0.296  1.0
  Si  Si11  1  0.978  0.333  0.704  1.0
[/CIF]
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