The crystal structure described by Mg3Si4 crystallizes in the triclinic P1 space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to one Mg(4), two equivalent Mg(2), two equivalent Mg(6), one Si(4), one Si(5), two equivalent Si(2), and two equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 11-coordinate geometry to one Mg(3), two equivalent Mg(1), two equivalent Mg(4), one Si(3), one Si(6), two equivalent Si(5), and two equivalent Si(8) atoms. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to one Mg(2), one Mg(5), two equivalent Mg(6), one Si(7), two equivalent Si(1), and two equivalent Si(8) atoms. In the fourth Mg site, Mg(4) is bonded in a 11-coordinate geometry to one Mg(1), two equivalent Mg(2), one Si(1), one Si(3), two equivalent Si(2), two equivalent Si(4), and two equivalent Si(6) atoms. In the fifth Mg site, Mg(5) is bonded in a 10-coordinate geometry to one Mg(3), one Si(1), one Si(2), one Si(8), two equivalent Si(5), two equivalent Si(6), and two equivalent Si(7) atoms. In the sixth Mg site, Mg(6) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), one Si(1), one Si(2), one Si(3), one Si(8), two equivalent Si(4), and two equivalent Si(7) atoms. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Mg(4), one Mg(5), one Mg(6), two equivalent Mg(3), two equivalent Si(2), and two equivalent Si(4) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(5), one Mg(6), two equivalent Mg(1), two equivalent Mg(4), one Si(7), and two equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Mg(2), one Mg(4), one Mg(6), two equivalent Mg(1), two equivalent Si(4), and two equivalent Si(5) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Mg(1), two equivalent Mg(4), two equivalent Mg(6), two equivalent Si(1), and two equivalent Si(3) atoms. In the fifth Si site, Si(5) is bonded in a 8-coordinate geometry to one Mg(1), two equivalent Mg(2), two equivalent Mg(5), one Si(6), and two equivalent Si(3) atoms. In the sixth Si site, Si(6) is bonded in a 8-coordinate geometry to one Mg(2), two equivalent Mg(4), two equivalent Mg(5), one Si(5), and two equivalent Si(8) atoms. In the seventh Si site, Si(7) is bonded in a 4-coordinate geometry to one Mg(3), two equivalent Mg(5), two equivalent Mg(6), one Si(2), and two equivalent Si(8) atoms. In the eighth Si site, Si(8) is bonded in a 10-coordinate geometry to one Mg(5), one Mg(6), two equivalent Mg(2), two equivalent Mg(3), two equivalent Si(6), and two equivalent Si(7) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.589
_cell_length_b   7.806
_cell_length_c   9.766
_cell_angle_alpha   68.313
_cell_angle_beta   80.644
_cell_angle_gamma   78.160
_symmetry_Int_Tables_number   1
_cell_volume   247.706
_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  0.790  0.109  0.359  1.0
  Mg  Mg1  1  0.417  0.082  0.109  1.0
  Mg  Mg2  1  0.527  0.274  0.790  1.0
  Mg  Mg3  1  0.005  0.750  0.284  1.0
  Mg  Mg4  1  0.270  0.624  0.844  1.0
  Mg  Mg5  1  0.151  0.186  0.573  1.0
  Si  Si6  1  0.969  0.546  0.599  1.0
  Si  Si7  1  0.379  0.799  0.533  1.0
  Si  Si8  1  0.204  0.414  0.235  1.0
  Si  Si9  1  0.576  0.464  0.430  1.0
  Si  Si10  1  0.783  0.396  0.060  1.0
  Si  Si11  1  0.632  0.728  0.052  1.0
  Si  Si12  1  0.697  0.921  0.725  1.0
  Si  Si13  1  0.100  0.959  0.907  1.0
[/CIF]
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The crystal structure described by Mg3Si4 crystallizes in the triclinic P1 space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to one Mg(4), two equivalent Mg(2), two equivalent Mg(6), one Si(4), one Si(5), two equivalent Si(2), and two equivalent Si(3) atoms. In the second Mg site, Mg(2) is bonded in a 11-coordinate geometry to one Mg(3), two equivalent Mg(1), two equivalent Mg(4), one Si(3), one Si(6), two equivalent Si(5), and two equivalent Si(8) atoms. In the third Mg site, Mg(3) is bonded in a 5-coordinate geometry to one Mg(2), one Mg(5), two equivalent Mg(6), one Si(7), two equivalent Si(1), and two equivalent Si(8) atoms. In the fourth Mg site, Mg(4) is bonded in a 11-coordinate geometry to one Mg(1), two equivalent Mg(2), one Si(1), one Si(3), two equivalent Si(2), two equivalent Si(4), and two equivalent Si(6) atoms. In the fifth Mg site, Mg(5) is bonded in a 10-coordinate geometry to one Mg(3), one Si(1), one Si(2), one Si(8), two equivalent Si(5), two equivalent Si(6), and two equivalent Si(7) atoms. In the sixth Mg site, Mg(6) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), one Si(1), one Si(2), one Si(3), one Si(8), two equivalent Si(4), and two equivalent Si(7) atoms. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Mg(4), one Mg(5), one Mg(6), two equivalent Mg(3), two equivalent Si(2), and two equivalent Si(4) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(5), one Mg(6), two equivalent Mg(1), two equivalent Mg(4), one Si(7), and two equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Mg(2), one Mg(4), one Mg(6), two equivalent Mg(1), two equivalent Si(4), and two equivalent Si(5) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Mg(1), two equivalent Mg(4), two equivalent Mg(6), two equivalent Si(1), and two equivalent Si(3) atoms. In the fifth Si site, Si(5) is bonded in a 8-coordinate geometry to one Mg(1), two equivalent Mg(2), two equivalent Mg(5), one Si(6), and two equivalent Si(3) atoms. In the sixth Si site, Si(6) is bonded in a 8-coordinate geometry to one Mg(2), two equivalent Mg(4), two equivalent Mg(5), one Si(5), and two equivalent Si(8) atoms. In the seventh Si site, Si(7) is bonded in a 4-coordinate geometry to one Mg(3), two equivalent Mg(5), two equivalent Mg(6), one Si(2), and two equivalent Si(8) atoms. In the eighth Si site, Si(8) is bonded in a 10-coordinate geometry to one Mg(5), one Mg(6), two equivalent Mg(2), two equivalent Mg(3), two equivalent Si(6), and two equivalent Si(7) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.589
_cell_length_b   7.806
_cell_length_c   9.766
_cell_angle_alpha   68.313
_cell_angle_beta   80.644
_cell_angle_gamma   78.160
_symmetry_Int_Tables_number   1
_cell_volume   247.706
_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  0.790  0.109  0.359  1.0
  Mg  Mg1  1  0.417  0.082  0.109  1.0
  Mg  Mg2  1  0.527  0.274  0.790  1.0
  Mg  Mg3  1  0.005  0.750  0.284  1.0
  Mg  Mg4  1  0.270  0.624  0.844  1.0
  Mg  Mg5  1  0.151  0.186  0.573  1.0
  Si  Si6  1  0.969  0.546  0.599  1.0
  Si  Si7  1  0.379  0.799  0.533  1.0
  Si  Si8  1  0.204  0.414  0.235  1.0
  Si  Si9  1  0.576  0.464  0.430  1.0
  Si  Si10  1  0.783  0.396  0.060  1.0
  Si  Si11  1  0.632  0.728  0.052  1.0
  Si  Si12  1  0.697  0.921  0.725  1.0
  Si  Si13  1  0.100  0.959  0.907  1.0
[/CIF]
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