The crystal structure described by Mg2Si3 is Magnesium tetraboride-like structured and 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 5-coordinate geometry to one Si(1), one Si(4), one Si(6), and three equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 1-coordinate geometry to three equivalent Si(2), three equivalent Si(4), and three equivalent Si(5) atoms. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to one Si(2), one Si(3), one Si(4), one Si(5), one Si(6), and two equivalent Si(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 5-coordinate geometry to one Si(1), one Si(3), one Si(5), and two equivalent Si(4) atoms. There are six 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), one Si(2), one Si(3), one Si(5), and one Si(6) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(3), three equivalent Mg(2), one Si(1), one Si(4), and three equivalent Si(5) atoms. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to one Mg(3), one Mg(4), three equivalent Mg(1), one Si(1), and two equivalent Si(6) atoms. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to one Mg(1), one Mg(3), two equivalent Mg(4), three equivalent Mg(2), and one Si(2) atom. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to one Mg(3), one Mg(4), three equivalent Mg(2), one Si(1), and three equivalent Si(2) atoms. In the sixth Si site, Si(6) is bonded in a 6-coordinate geometry to one Mg(1), one Mg(3), one Si(1), one Si(6), and two equivalent Si(3) atoms. is represented by the CIF card [CIF]
data_Mg2Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.545
_cell_length_b   7.002
_cell_length_c   11.905
_cell_angle_alpha   88.618
_cell_angle_beta   79.626
_cell_angle_gamma   88.166
_symmetry_Int_Tables_number   1
_cell_volume   372.388
_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  0.809  0.373  0.593  1.0
  Mg  Mg1  1  0.753  0.679  0.007  1.0
  Mg  Mg2  1  0.269  0.205  0.724  1.0
  Mg  Mg3  1  0.300  0.640  0.760  1.0
  Mg  Mg4  1  0.247  0.321  0.993  1.0
  Mg  Mg5  1  0.191  0.627  0.407  1.0
  Mg  Mg6  1  0.700  0.360  0.240  1.0
  Mg  Mg7  1  0.731  0.795  0.276  1.0
  Si  Si8  1  0.745  0.951  0.702  1.0
  Si  Si9  1  0.789  0.093  0.892  1.0
  Si  Si10  1  0.632  0.736  0.538  1.0
  Si  Si11  1  0.784  0.426  0.832  1.0
  Si  Si12  1  0.706  0.057  0.102  1.0
  Si  Si13  1  0.800  0.047  0.445  1.0
  Si  Si14  1  0.211  0.907  0.108  1.0
  Si  Si15  1  0.255  0.049  0.298  1.0
  Si  Si16  1  0.216  0.574  0.168  1.0
  Si  Si17  1  0.368  0.264  0.462  1.0
  Si  Si18  1  0.200  0.953  0.555  1.0
  Si  Si19  1  0.294  0.943  0.898  1.0
[/CIF]
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The crystal structure described by Mg2Si3 is Magnesium tetraboride-like structured and 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 5-coordinate geometry to one Si(1), one Si(4), one Si(6), and three equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 1-coordinate geometry to three equivalent Si(2), three equivalent Si(4), and three equivalent Si(5) atoms. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to one Si(2), one Si(3), one Si(4), one Si(5), one Si(6), and two equivalent Si(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 5-coordinate geometry to one Si(1), one Si(3), one Si(5), and two equivalent Si(4) atoms. There are six 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), one Si(2), one Si(3), one Si(5), and one Si(6) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(3), three equivalent Mg(2), one Si(1), one Si(4), and three equivalent Si(5) atoms. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to one Mg(3), one Mg(4), three equivalent Mg(1), one Si(1), and two equivalent Si(6) atoms. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to one Mg(1), one Mg(3), two equivalent Mg(4), three equivalent Mg(2), and one Si(2) atom. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to one Mg(3), one Mg(4), three equivalent Mg(2), one Si(1), and three equivalent Si(2) atoms. In the sixth Si site, Si(6) is bonded in a 6-coordinate geometry to one Mg(1), one Mg(3), one Si(1), one Si(6), and two equivalent Si(3) atoms. is represented by the CIF card [CIF]
data_Mg2Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.545
_cell_length_b   7.002
_cell_length_c   11.905
_cell_angle_alpha   88.618
_cell_angle_beta   79.626
_cell_angle_gamma   88.166
_symmetry_Int_Tables_number   1
_cell_volume   372.388
_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  0.809  0.373  0.593  1.0
  Mg  Mg1  1  0.753  0.679  0.007  1.0
  Mg  Mg2  1  0.269  0.205  0.724  1.0
  Mg  Mg3  1  0.300  0.640  0.760  1.0
  Mg  Mg4  1  0.247  0.321  0.993  1.0
  Mg  Mg5  1  0.191  0.627  0.407  1.0
  Mg  Mg6  1  0.700  0.360  0.240  1.0
  Mg  Mg7  1  0.731  0.795  0.276  1.0
  Si  Si8  1  0.745  0.951  0.702  1.0
  Si  Si9  1  0.789  0.093  0.892  1.0
  Si  Si10  1  0.632  0.736  0.538  1.0
  Si  Si11  1  0.784  0.426  0.832  1.0
  Si  Si12  1  0.706  0.057  0.102  1.0
  Si  Si13  1  0.800  0.047  0.445  1.0
  Si  Si14  1  0.211  0.907  0.108  1.0
  Si  Si15  1  0.255  0.049  0.298  1.0
  Si  Si16  1  0.216  0.574  0.168  1.0
  Si  Si17  1  0.368  0.264  0.462  1.0
  Si  Si18  1  0.200  0.953  0.555  1.0
  Si  Si19  1  0.294  0.943  0.898  1.0
[/CIF]
.