The structure described by Mg2(AlSi2)3 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), one Al(1), one Al(2), two equivalent Si(2), three equivalent Si(1), and three equivalent Si(3) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 11-coordinate geometry to one Mg(1), one Al(1), one Al(2), two equivalent Si(1), two equivalent Si(3), and four equivalent Si(2) atoms. In the second Al site, Al(2) is bonded in a 6-coordinate geometry to two equivalent Mg(1), two equivalent Al(1), and four equivalent Si(2) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to three equivalent Mg(1), two equivalent Al(1), one Si(2), and three equivalent Si(3) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Al(2), four equivalent Al(1), one Si(1), and one Si(2) atom. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to three equivalent Mg(1), two equivalent Al(1), and three equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Mg2(AlSi2)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.707
_cell_length_b   7.707
_cell_length_c   6.529
_cell_angle_alpha   76.683
_cell_angle_beta   76.683
_cell_angle_gamma   28.899
_symmetry_Int_Tables_number   1
_cell_volume   182.004
_cell_formula_units_Z   1
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  0.173  0.173  0.073  1.0
  Mg  Mg1  1  0.827  0.827  0.927  1.0
  Al  Al2  1  0.911  0.911  0.447  1.0
  Al  Al3  1  0.089  0.089  0.553  1.0
  Al  Al4  1  0.000  0.000  0.000  1.0
  Si  Si5  1  0.705  0.705  0.352  1.0
  Si  Si6  1  0.295  0.295  0.648  1.0
  Si  Si7  1  0.534  0.534  0.287  1.0
  Si  Si8  1  0.466  0.466  0.713  1.0
  Si  Si9  1  0.336  0.336  0.254  1.0
  Si  Si10  1  0.664  0.664  0.746  1.0
[/CIF]
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The structure described by Mg2(AlSi2)3 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), one Al(1), one Al(2), two equivalent Si(2), three equivalent Si(1), and three equivalent Si(3) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 11-coordinate geometry to one Mg(1), one Al(1), one Al(2), two equivalent Si(1), two equivalent Si(3), and four equivalent Si(2) atoms. In the second Al site, Al(2) is bonded in a 6-coordinate geometry to two equivalent Mg(1), two equivalent Al(1), and four equivalent Si(2) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to three equivalent Mg(1), two equivalent Al(1), one Si(2), and three equivalent Si(3) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Al(2), four equivalent Al(1), one Si(1), and one Si(2) atom. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to three equivalent Mg(1), two equivalent Al(1), and three equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Mg2(AlSi2)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.707
_cell_length_b   7.707
_cell_length_c   6.529
_cell_angle_alpha   76.683
_cell_angle_beta   76.683
_cell_angle_gamma   28.899
_symmetry_Int_Tables_number   1
_cell_volume   182.004
_cell_formula_units_Z   1
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  0.173  0.173  0.073  1.0
  Mg  Mg1  1  0.827  0.827  0.927  1.0
  Al  Al2  1  0.911  0.911  0.447  1.0
  Al  Al3  1  0.089  0.089  0.553  1.0
  Al  Al4  1  0.000  0.000  0.000  1.0
  Si  Si5  1  0.705  0.705  0.352  1.0
  Si  Si6  1  0.295  0.295  0.648  1.0
  Si  Si7  1  0.534  0.534  0.287  1.0
  Si  Si8  1  0.466  0.466  0.713  1.0
  Si  Si9  1  0.336  0.336  0.254  1.0
  Si  Si10  1  0.664  0.664  0.746  1.0
[/CIF]
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