The material 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 6-coordinate geometry to one Si(1), one Si(2), two equivalent Si(3), and two equivalent Si(6) atoms. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Si(6), four equivalent Si(1), and four equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 6-coordinate geometry to one Si(4), one Si(5), two equivalent Si(3), and two equivalent Si(6) atoms. In the fourth Mg site, Mg(4) is bonded in a 3-coordinate geometry to two equivalent Si(3), four equivalent Si(4), and four equivalent Si(5) atoms. There are six inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Mg(2), one Si(1), and three equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Mg(2), one Si(6), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(4), one Si(5), and one Si(6) atom. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(4), one Si(4), and three equivalent Si(5) atoms. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(4), one Si(3), and three equivalent Si(4) atoms. In the sixth Si site, Si(6) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), one Si(2), and one Si(3) atom. is represented by the CIF card [CIF]
data_Mg2Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.488
_cell_length_b   5.275
_cell_length_c   8.465
_cell_angle_alpha   86.784
_cell_angle_beta   77.823
_cell_angle_gamma   67.363
_symmetry_Int_Tables_number   1
_cell_volume   180.741
_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  0.391  0.779  0.400  1.0
  Mg  Mg1  1  0.609  0.221  0.600  1.0
  Mg  Mg2  1  0.819  0.183  0.194  1.0
  Mg  Mg3  1  0.181  0.817  0.806  1.0
  Si  Si4  1  0.600  0.767  0.050  1.0
  Si  Si5  1  0.873  0.390  0.848  1.0
  Si  Si6  1  0.127  0.610  0.152  1.0
  Si  Si7  1  0.400  0.233  0.950  1.0
  Si  Si8  1  0.170  0.338  0.389  1.0
  Si  Si9  1  0.830  0.662  0.611  1.0
[/CIF]
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The material 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 6-coordinate geometry to one Si(1), one Si(2), two equivalent Si(3), and two equivalent Si(6) atoms. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Si(6), four equivalent Si(1), and four equivalent Si(2) atoms. In the third Mg site, Mg(3) is bonded in a 6-coordinate geometry to one Si(4), one Si(5), two equivalent Si(3), and two equivalent Si(6) atoms. In the fourth Mg site, Mg(4) is bonded in a 3-coordinate geometry to two equivalent Si(3), four equivalent Si(4), and four equivalent Si(5) atoms. There are six inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Mg(2), one Si(1), and three equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Mg(2), one Si(6), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(4), one Si(5), and one Si(6) atom. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(4), one Si(4), and three equivalent Si(5) atoms. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to one Mg(3), four equivalent Mg(4), one Si(3), and three equivalent Si(4) atoms. In the sixth Si site, Si(6) is bonded in a 8-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), one Si(2), and one Si(3) atom. is represented by the CIF card [CIF]
data_Mg2Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.488
_cell_length_b   5.275
_cell_length_c   8.465
_cell_angle_alpha   86.784
_cell_angle_beta   77.823
_cell_angle_gamma   67.363
_symmetry_Int_Tables_number   1
_cell_volume   180.741
_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  0.391  0.779  0.400  1.0
  Mg  Mg1  1  0.609  0.221  0.600  1.0
  Mg  Mg2  1  0.819  0.183  0.194  1.0
  Mg  Mg3  1  0.181  0.817  0.806  1.0
  Si  Si4  1  0.600  0.767  0.050  1.0
  Si  Si5  1  0.873  0.390  0.848  1.0
  Si  Si6  1  0.127  0.610  0.152  1.0
  Si  Si7  1  0.400  0.233  0.950  1.0
  Si  Si8  1  0.170  0.338  0.389  1.0
  Si  Si9  1  0.830  0.662  0.611  1.0
[/CIF]
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