The material 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 3-coordinate geometry to one Si(2), one Si(5), and one Si(8) atom. In the second Mg site, Mg(2) is bonded in a 2-coordinate geometry to one Mg(6), one Si(1), and one Si(6) atom. In the third Mg site, Mg(3) is bonded in a 4-coordinate geometry to one Si(3), one Si(4), one Si(5), and one Si(7) atom. In the fourth Mg site, Mg(4) is bonded in a 6-coordinate geometry to one Mg(5), one Mg(6), one Si(2), one Si(5), one Si(6), and one Si(7) atom. In the fifth Mg site, Mg(5) is bonded in a 2-coordinate geometry to one Mg(4), one Si(4), and one Si(6) atom. In the sixth Mg site, Mg(6) is bonded in a 4-coordinate geometry to one Mg(2), one Mg(4), one Si(2), and one Si(3) atom. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted single-bond geometry to one Mg(2) and one Si(2) atom. In the second Si site, Si(2) is bonded in a 5-coordinate geometry to one Mg(1), one Mg(4), one Mg(6), one Si(1), and one Si(8) atom. In the third Si site, Si(3) is bonded in a distorted single-bond geometry to one Mg(3) and one Mg(6) atom. In the fourth Si site, Si(4) is bonded in a distorted single-bond geometry to one Mg(3) and one Mg(5) atom. In the fifth Si site, Si(5) is bonded in a 2-coordinate geometry to one Mg(1), one Mg(3), and one Mg(4) atom. In the sixth Si site, Si(6) is bonded in a 3-coordinate geometry to one Mg(2), one Mg(4), and one Mg(5) atom. In the seventh Si site, Si(7) is bonded in a 2-coordinate geometry to one Mg(3) and one Mg(4) atom. In the eighth Si site, Si(8) is bonded in a distorted single-bond geometry to one Mg(1) and one Si(2) atom. is represented by the CIF card [CIF]
data_Mg3Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.080
_cell_length_b   6.859
_cell_length_c   7.574
_cell_angle_alpha   112.253
_cell_angle_beta   99.266
_cell_angle_gamma   107.904
_symmetry_Int_Tables_number   1
_cell_volume   264.006
_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  0.408  0.112  0.396  1.0
  Mg  Mg1  1  0.968  0.305  0.448  1.0
  Mg  Mg2  1  0.645  0.276  0.879  1.0
  Mg  Mg3  1  0.868  0.843  0.790  1.0
  Mg  Mg4  1  0.660  0.616  0.427  1.0
  Mg  Mg5  1  0.963  0.119  0.131  1.0
  Si  Si6  1  0.198  0.540  0.773  1.0
  Si  Si7  1  0.188  0.860  0.025  1.0
  Si  Si8  1  0.869  0.483  0.107  1.0
  Si  Si9  1  0.452  0.484  0.122  1.0
  Si  Si10  1  0.268  0.212  0.732  1.0
  Si  Si11  1  0.064  0.673  0.522  1.0
  Si  Si12  1  0.499  0.919  0.699  1.0
  Si  Si13  1  0.449  0.811  0.197  1.0
[/CIF]
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The material 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 3-coordinate geometry to one Si(2), one Si(5), and one Si(8) atom. In the second Mg site, Mg(2) is bonded in a 2-coordinate geometry to one Mg(6), one Si(1), and one Si(6) atom. In the third Mg site, Mg(3) is bonded in a 4-coordinate geometry to one Si(3), one Si(4), one Si(5), and one Si(7) atom. In the fourth Mg site, Mg(4) is bonded in a 6-coordinate geometry to one Mg(5), one Mg(6), one Si(2), one Si(5), one Si(6), and one Si(7) atom. In the fifth Mg site, Mg(5) is bonded in a 2-coordinate geometry to one Mg(4), one Si(4), and one Si(6) atom. In the sixth Mg site, Mg(6) is bonded in a 4-coordinate geometry to one Mg(2), one Mg(4), one Si(2), and one Si(3) atom. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted single-bond geometry to one Mg(2) and one Si(2) atom. In the second Si site, Si(2) is bonded in a 5-coordinate geometry to one Mg(1), one Mg(4), one Mg(6), one Si(1), and one Si(8) atom. In the third Si site, Si(3) is bonded in a distorted single-bond geometry to one Mg(3) and one Mg(6) atom. In the fourth Si site, Si(4) is bonded in a distorted single-bond geometry to one Mg(3) and one Mg(5) atom. In the fifth Si site, Si(5) is bonded in a 2-coordinate geometry to one Mg(1), one Mg(3), and one Mg(4) atom. In the sixth Si site, Si(6) is bonded in a 3-coordinate geometry to one Mg(2), one Mg(4), and one Mg(5) atom. In the seventh Si site, Si(7) is bonded in a 2-coordinate geometry to one Mg(3) and one Mg(4) atom. In the eighth Si site, Si(8) is bonded in a distorted single-bond geometry to one Mg(1) and one Si(2) atom. is represented by the CIF card [CIF]
data_Mg3Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.080
_cell_length_b   6.859
_cell_length_c   7.574
_cell_angle_alpha   112.253
_cell_angle_beta   99.266
_cell_angle_gamma   107.904
_symmetry_Int_Tables_number   1
_cell_volume   264.006
_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  0.408  0.112  0.396  1.0
  Mg  Mg1  1  0.968  0.305  0.448  1.0
  Mg  Mg2  1  0.645  0.276  0.879  1.0
  Mg  Mg3  1  0.868  0.843  0.790  1.0
  Mg  Mg4  1  0.660  0.616  0.427  1.0
  Mg  Mg5  1  0.963  0.119  0.131  1.0
  Si  Si6  1  0.198  0.540  0.773  1.0
  Si  Si7  1  0.188  0.860  0.025  1.0
  Si  Si8  1  0.869  0.483  0.107  1.0
  Si  Si9  1  0.452  0.484  0.122  1.0
  Si  Si10  1  0.268  0.212  0.732  1.0
  Si  Si11  1  0.064  0.673  0.522  1.0
  Si  Si12  1  0.499  0.919  0.699  1.0
  Si  Si13  1  0.449  0.811  0.197  1.0
[/CIF]
.