The compound described by Mg4AlSi3 crystallizes in the tetragonal P4/ncc space group. Mg(1) is bonded in a 5-coordinate geometry to one Al(1), two equivalent Si(1), and three equivalent Si(2) atoms. Al(1) is bonded in a 9-coordinate geometry to four equivalent Mg(1), one Si(1), and four equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to eight equivalent Mg(1) and one Al(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to six equivalent Mg(1), two equivalent Al(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_Mg4AlSi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.559
_cell_length_b   6.559
_cell_length_c   13.821
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   594.620
_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  0.816  0.156  0.097  1.0
  Mg  Mg1  1  0.184  0.156  0.597  1.0
  Mg  Mg2  1  0.816  0.844  0.597  1.0
  Mg  Mg3  1  0.184  0.844  0.097  1.0
  Mg  Mg4  1  0.656  0.316  0.597  1.0
  Mg  Mg5  1  0.344  0.316  0.097  1.0
  Mg  Mg6  1  0.656  0.684  0.097  1.0
  Mg  Mg7  1  0.344  0.684  0.597  1.0
  Mg  Mg8  1  0.684  0.344  0.903  1.0
  Mg  Mg9  1  0.316  0.344  0.403  1.0
  Mg  Mg10  1  0.684  0.656  0.403  1.0
  Mg  Mg11  1  0.316  0.656  0.903  1.0
  Mg  Mg12  1  0.844  0.184  0.403  1.0
  Mg  Mg13  1  0.156  0.184  0.903  1.0
  Mg  Mg14  1  0.844  0.816  0.903  1.0
  Mg  Mg15  1  0.156  0.816  0.403  1.0
  Al  Al16  1  0.000  0.500  0.219  1.0
  Al  Al17  1  0.000  0.500  0.719  1.0
  Al  Al18  1  0.500  0.000  0.781  1.0
  Al  Al19  1  0.500  0.000  0.281  1.0
  Si  Si20  1  0.000  0.500  0.016  1.0
  Si  Si21  1  0.000  0.500  0.516  1.0
  Si  Si22  1  0.500  0.000  0.984  1.0
  Si  Si23  1  0.500  0.000  0.484  1.0
  Si  Si24  1  0.633  0.367  0.250  1.0
  Si  Si25  1  0.367  0.367  0.750  1.0
  Si  Si26  1  0.633  0.633  0.750  1.0
  Si  Si27  1  0.367  0.633  0.250  1.0
  Si  Si28  1  0.867  0.133  0.750  1.0
  Si  Si29  1  0.133  0.133  0.250  1.0
  Si  Si30  1  0.867  0.867  0.250  1.0
  Si  Si31  1  0.133  0.867  0.750  1.0
[/CIF]
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The compound described by Mg4AlSi3 crystallizes in the tetragonal P4/ncc space group. Mg(1) is bonded in a 5-coordinate geometry to one Al(1), two equivalent Si(1), and three equivalent Si(2) atoms. Al(1) is bonded in a 9-coordinate geometry to four equivalent Mg(1), one Si(1), and four equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to eight equivalent Mg(1) and one Al(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to six equivalent Mg(1), two equivalent Al(1), and one Si(2) atom. is represented by the CIF file [CIF]
data_Mg4AlSi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.559
_cell_length_b   6.559
_cell_length_c   13.821
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   594.620
_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  0.816  0.156  0.097  1.0
  Mg  Mg1  1  0.184  0.156  0.597  1.0
  Mg  Mg2  1  0.816  0.844  0.597  1.0
  Mg  Mg3  1  0.184  0.844  0.097  1.0
  Mg  Mg4  1  0.656  0.316  0.597  1.0
  Mg  Mg5  1  0.344  0.316  0.097  1.0
  Mg  Mg6  1  0.656  0.684  0.097  1.0
  Mg  Mg7  1  0.344  0.684  0.597  1.0
  Mg  Mg8  1  0.684  0.344  0.903  1.0
  Mg  Mg9  1  0.316  0.344  0.403  1.0
  Mg  Mg10  1  0.684  0.656  0.403  1.0
  Mg  Mg11  1  0.316  0.656  0.903  1.0
  Mg  Mg12  1  0.844  0.184  0.403  1.0
  Mg  Mg13  1  0.156  0.184  0.903  1.0
  Mg  Mg14  1  0.844  0.816  0.903  1.0
  Mg  Mg15  1  0.156  0.816  0.403  1.0
  Al  Al16  1  0.000  0.500  0.219  1.0
  Al  Al17  1  0.000  0.500  0.719  1.0
  Al  Al18  1  0.500  0.000  0.781  1.0
  Al  Al19  1  0.500  0.000  0.281  1.0
  Si  Si20  1  0.000  0.500  0.016  1.0
  Si  Si21  1  0.000  0.500  0.516  1.0
  Si  Si22  1  0.500  0.000  0.984  1.0
  Si  Si23  1  0.500  0.000  0.484  1.0
  Si  Si24  1  0.633  0.367  0.250  1.0
  Si  Si25  1  0.367  0.367  0.750  1.0
  Si  Si26  1  0.633  0.633  0.750  1.0
  Si  Si27  1  0.367  0.633  0.250  1.0
  Si  Si28  1  0.867  0.133  0.750  1.0
  Si  Si29  1  0.133  0.133  0.250  1.0
  Si  Si30  1  0.867  0.867  0.250  1.0
  Si  Si31  1  0.133  0.867  0.750  1.0
[/CIF]
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