The material described by Mg3Si2 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 5-coordinate geometry to two equivalent Si(1) and three equivalent Si(2) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Si(2) and three equivalent Si(1) atoms. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to two equivalent Si(2) and three equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Mg(1), three equivalent Mg(2), three equivalent Mg(3), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), three 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   5.362
_cell_length_b   5.295
_cell_length_c   13.507
_cell_angle_alpha   82.088
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   379.830
_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  0.134  0.355  0.740  1.0
  Mg  Mg1  1  0.634  0.645  0.760  1.0
  Mg  Mg2  1  0.113  0.825  0.874  1.0
  Mg  Mg3  1  0.613  0.175  0.626  1.0
  Mg  Mg4  1  0.387  0.825  0.374  1.0
  Mg  Mg5  1  0.347  0.254  0.991  1.0
  Mg  Mg6  1  0.366  0.355  0.240  1.0
  Mg  Mg7  1  0.866  0.645  0.260  1.0
  Mg  Mg8  1  0.153  0.254  0.491  1.0
  Mg  Mg9  1  0.887  0.175  0.126  1.0
  Mg  Mg10  1  0.653  0.746  0.009  1.0
  Mg  Mg11  1  0.847  0.746  0.509  1.0
  Si  Si12  1  0.860  0.338  0.923  1.0
  Si  Si13  1  0.360  0.662  0.577  1.0
  Si  Si14  1  0.577  0.102  0.830  1.0
  Si  Si15  1  0.077  0.898  0.670  1.0
  Si  Si16  1  0.640  0.338  0.423  1.0
  Si  Si17  1  0.140  0.662  0.077  1.0
  Si  Si18  1  0.923  0.102  0.330  1.0
  Si  Si19  1  0.423  0.898  0.170  1.0
[/CIF]
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The material described by Mg3Si2 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 5-coordinate geometry to two equivalent Si(1) and three equivalent Si(2) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Si(2) and three equivalent Si(1) atoms. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to two equivalent Si(2) and three equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Mg(1), three equivalent Mg(2), three equivalent Mg(3), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), three 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   5.362
_cell_length_b   5.295
_cell_length_c   13.507
_cell_angle_alpha   82.088
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   379.830
_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  0.134  0.355  0.740  1.0
  Mg  Mg1  1  0.634  0.645  0.760  1.0
  Mg  Mg2  1  0.113  0.825  0.874  1.0
  Mg  Mg3  1  0.613  0.175  0.626  1.0
  Mg  Mg4  1  0.387  0.825  0.374  1.0
  Mg  Mg5  1  0.347  0.254  0.991  1.0
  Mg  Mg6  1  0.366  0.355  0.240  1.0
  Mg  Mg7  1  0.866  0.645  0.260  1.0
  Mg  Mg8  1  0.153  0.254  0.491  1.0
  Mg  Mg9  1  0.887  0.175  0.126  1.0
  Mg  Mg10  1  0.653  0.746  0.009  1.0
  Mg  Mg11  1  0.847  0.746  0.509  1.0
  Si  Si12  1  0.860  0.338  0.923  1.0
  Si  Si13  1  0.360  0.662  0.577  1.0
  Si  Si14  1  0.577  0.102  0.830  1.0
  Si  Si15  1  0.077  0.898  0.670  1.0
  Si  Si16  1  0.640  0.338  0.423  1.0
  Si  Si17  1  0.140  0.662  0.077  1.0
  Si  Si18  1  0.923  0.102  0.330  1.0
  Si  Si19  1  0.423  0.898  0.170  1.0
[/CIF]
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