The structure described by Mg2Si3 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 3-coordinate geometry to one Si(1) and five equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 11-coordinate geometry to two equivalent Si(3), four equivalent Si(2), and five equivalent Si(1) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 11-coordinate geometry to one Mg(1), five equivalent Mg(2), one Si(1), one Si(3), and three equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to four equivalent Mg(2), one Si(3), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 10-coordinate geometry to two equivalent Mg(2), five equivalent Mg(1), one Si(1), one Si(2), and one Si(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.193
_cell_length_b   5.193
_cell_length_c   8.306
_cell_angle_alpha   77.300
_cell_angle_beta   77.300
_cell_angle_gamma   52.328
_symmetry_Int_Tables_number   1
_cell_volume   171.882
_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  0.168  0.168  0.960  1.0
  Mg  Mg1  1  0.832  0.832  0.040  1.0
  Mg  Mg2  1  0.048  0.048  0.657  1.0
  Mg  Mg3  1  0.952  0.952  0.343  1.0
  Si  Si4  1  0.369  0.369  0.587  1.0
  Si  Si5  1  0.272  0.272  0.322  1.0
  Si  Si6  1  0.728  0.728  0.678  1.0
  Si  Si7  1  0.631  0.631  0.413  1.0
  Si  Si8  1  0.480  0.480  0.856  1.0
  Si  Si9  1  0.520  0.520  0.144  1.0
[/CIF]
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The structure described by Mg2Si3 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 3-coordinate geometry to one Si(1) and five equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 11-coordinate geometry to two equivalent Si(3), four equivalent Si(2), and five equivalent Si(1) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 11-coordinate geometry to one Mg(1), five equivalent Mg(2), one Si(1), one Si(3), and three equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to four equivalent Mg(2), one Si(3), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 10-coordinate geometry to two equivalent Mg(2), five equivalent Mg(1), one Si(1), one Si(2), and one Si(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.193
_cell_length_b   5.193
_cell_length_c   8.306
_cell_angle_alpha   77.300
_cell_angle_beta   77.300
_cell_angle_gamma   52.328
_symmetry_Int_Tables_number   1
_cell_volume   171.882
_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  0.168  0.168  0.960  1.0
  Mg  Mg1  1  0.832  0.832  0.040  1.0
  Mg  Mg2  1  0.048  0.048  0.657  1.0
  Mg  Mg3  1  0.952  0.952  0.343  1.0
  Si  Si4  1  0.369  0.369  0.587  1.0
  Si  Si5  1  0.272  0.272  0.322  1.0
  Si  Si6  1  0.728  0.728  0.678  1.0
  Si  Si7  1  0.631  0.631  0.413  1.0
  Si  Si8  1  0.480  0.480  0.856  1.0
  Si  Si9  1  0.520  0.520  0.144  1.0
[/CIF]
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