The compound described by Mg3Si2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 6-coordinate geometry to six equivalent Si(1) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to four equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Mg(2), six equivalent Mg(1), and one Si(1) atom. is represented by the CIF file [CIF]
data_Mg3Si2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.210
_cell_length_b   5.210
_cell_length_c   4.391
_cell_angle_alpha   67.522
_cell_angle_beta   67.522
_cell_angle_gamma   96.620
_symmetry_Int_Tables_number   1
_cell_volume   96.886
_cell_formula_units_Z   1
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  0.704  0.296  0.500  1.0
  Mg  Mg1  1  0.296  0.704  0.500  1.0
  Mg  Mg2  1  0.000  0.000  0.000  1.0
  Si  Si3  1  0.708  0.708  0.773  1.0
  Si  Si4  1  0.292  0.292  0.227  1.0
[/CIF]
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The compound described by Mg3Si2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 6-coordinate geometry to six equivalent Si(1) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to four equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Mg(2), six equivalent Mg(1), and one Si(1) atom. is represented by the CIF file [CIF]
data_Mg3Si2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.210
_cell_length_b   5.210
_cell_length_c   4.391
_cell_angle_alpha   67.522
_cell_angle_beta   67.522
_cell_angle_gamma   96.620
_symmetry_Int_Tables_number   1
_cell_volume   96.886
_cell_formula_units_Z   1
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  0.704  0.296  0.500  1.0
  Mg  Mg1  1  0.296  0.704  0.500  1.0
  Mg  Mg2  1  0.000  0.000  0.000  1.0
  Si  Si3  1  0.708  0.708  0.773  1.0
  Si  Si4  1  0.292  0.292  0.227  1.0
[/CIF]
.