The compound described by Mg3Si2 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 4-coordinate geometry to one 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(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(2) and four 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 one Mg(1), two equivalent Mg(2), four equivalent Mg(3), one Si(1), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Mg(3), three equivalent Mg(1), three equivalent Mg(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3Si2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.262
_cell_length_b   5.546
_cell_length_c   7.212
_cell_angle_alpha   94.206
_cell_angle_beta   99.730
_cell_angle_gamma   107.381
_symmetry_Int_Tables_number   1
_cell_volume   196.235
_cell_formula_units_Z   2
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  0.444  0.265  0.092  1.0
  Mg  Mg1  1  0.556  0.735  0.908  1.0
  Mg  Mg2  1  0.099  0.688  0.177  1.0
  Mg  Mg3  1  0.901  0.312  0.823  1.0
  Mg  Mg4  1  0.697  0.790  0.454  1.0
  Mg  Mg5  1  0.303  0.210  0.546  1.0
  Si  Si6  1  0.797  0.319  0.438  1.0
  Si  Si7  1  0.203  0.681  0.562  1.0
  Si  Si8  1  0.923  0.120  0.177  1.0
  Si  Si9  1  0.077  0.880  0.823  1.0
[/CIF]
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The compound described by Mg3Si2 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 4-coordinate geometry to one 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(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(2) and four 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 one Mg(1), two equivalent Mg(2), four equivalent Mg(3), one Si(1), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Mg(3), three equivalent Mg(1), three equivalent Mg(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3Si2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.262
_cell_length_b   5.546
_cell_length_c   7.212
_cell_angle_alpha   94.206
_cell_angle_beta   99.730
_cell_angle_gamma   107.381
_symmetry_Int_Tables_number   1
_cell_volume   196.235
_cell_formula_units_Z   2
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  0.444  0.265  0.092  1.0
  Mg  Mg1  1  0.556  0.735  0.908  1.0
  Mg  Mg2  1  0.099  0.688  0.177  1.0
  Mg  Mg3  1  0.901  0.312  0.823  1.0
  Mg  Mg4  1  0.697  0.790  0.454  1.0
  Mg  Mg5  1  0.303  0.210  0.546  1.0
  Si  Si6  1  0.797  0.319  0.438  1.0
  Si  Si7  1  0.203  0.681  0.562  1.0
  Si  Si8  1  0.923  0.120  0.177  1.0
  Si  Si9  1  0.077  0.880  0.823  1.0
[/CIF]
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