The crystal structure described by Mg16Al12Sn crystallizes in the trigonal R3m space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to one Mg(4), two equivalent Mg(2), four equivalent Mg(5), one Al(1), and four equivalent Al(3) atoms. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(1), four equivalent Mg(5), one Al(2), two equivalent Al(1), two equivalent Al(3), and one Sn(1) atom. In the third Mg site, Mg(3) is bonded in a 16-coordinate geometry to three equivalent Mg(4), three equivalent Al(1), three equivalent Al(2), six equivalent Al(3), and one Sn(1) atom. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to one Mg(1), one Mg(3), two equivalent Mg(5), two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the fifth Mg site, Mg(5) is bonded in a 12-coordinate geometry to one Mg(4), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(5), one Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted q6 geometry to one Mg(1), one Mg(3), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), one Al(2), and two equivalent Al(1) atoms. In the second Al site, Al(2) is bonded in a 11-coordinate geometry to one Mg(2), one Mg(3), two equivalent Mg(4), four equivalent Mg(5), one Al(1), and two equivalent Al(3) atoms. In the third Al site, Al(3) is bonded in a 11-coordinate geometry to one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(1), two equivalent Mg(5), one Al(2), two equivalent Al(3), and one Sn(1) atom. Sn(1) is bonded in a 10-coordinate geometry to one Mg(3), three equivalent Mg(2), and six equivalent Al(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg16Al12Sn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.151
_cell_length_b   9.151
_cell_length_c   9.151
_cell_angle_alpha   109.432
_cell_angle_beta   109.432
_cell_angle_gamma   109.432
_symmetry_Int_Tables_number   1
_cell_volume   590.784
_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  0.684  0.684  0.286  1.0
  Mg  Mg1  1  0.398  0.398  0.710  1.0
  Mg  Mg2  1  0.002  0.002  0.002  1.0
  Mg  Mg3  1  0.999  0.999  0.346  1.0
  Mg  Mg4  1  0.599  0.317  0.001  1.0
  Mg  Mg5  1  0.710  0.398  0.398  1.0
  Mg  Mg6  1  0.317  0.001  0.599  1.0
  Mg  Mg7  1  0.346  0.999  0.999  1.0
  Mg  Mg8  1  0.684  0.286  0.684  1.0
  Mg  Mg9  1  0.001  0.599  0.317  1.0
  Mg  Mg10  1  0.599  0.001  0.317  1.0
  Mg  Mg11  1  0.286  0.684  0.684  1.0
  Mg  Mg12  1  0.999  0.346  0.999  1.0
  Mg  Mg13  1  0.001  0.317  0.599  1.0
  Mg  Mg14  1  0.398  0.710  0.398  1.0
  Mg  Mg15  1  0.317  0.599  0.001  1.0
  Al  Al16  1  0.363  0.363  0.176  1.0
  Al  Al17  1  0.184  0.184  0.816  1.0
  Al  Al18  1  0.817  0.632  0.005  1.0
  Al  Al19  1  0.363  0.176  0.363  1.0
  Al  Al20  1  0.005  0.817  0.632  1.0
  Al  Al21  1  0.184  0.816  0.184  1.0
  Al  Al22  1  0.005  0.632  0.817  1.0
  Al  Al23  1  0.632  0.005  0.817  1.0
  Al  Al24  1  0.816  0.184  0.184  1.0
  Al  Al25  1  0.817  0.005  0.632  1.0
  Al  Al26  1  0.176  0.363  0.363  1.0
  Al  Al27  1  0.632  0.817  0.005  1.0
  Sn  Sn28  1  0.666  0.666  0.666  1.0
[/CIF]
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The crystal structure described by Mg16Al12Sn crystallizes in the trigonal R3m space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to one Mg(4), two equivalent Mg(2), four equivalent Mg(5), one Al(1), and four equivalent Al(3) atoms. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(1), four equivalent Mg(5), one Al(2), two equivalent Al(1), two equivalent Al(3), and one Sn(1) atom. In the third Mg site, Mg(3) is bonded in a 16-coordinate geometry to three equivalent Mg(4), three equivalent Al(1), three equivalent Al(2), six equivalent Al(3), and one Sn(1) atom. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to one Mg(1), one Mg(3), two equivalent Mg(5), two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the fifth Mg site, Mg(5) is bonded in a 12-coordinate geometry to one Mg(4), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(5), one Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted q6 geometry to one Mg(1), one Mg(3), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), one Al(2), and two equivalent Al(1) atoms. In the second Al site, Al(2) is bonded in a 11-coordinate geometry to one Mg(2), one Mg(3), two equivalent Mg(4), four equivalent Mg(5), one Al(1), and two equivalent Al(3) atoms. In the third Al site, Al(3) is bonded in a 11-coordinate geometry to one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(1), two equivalent Mg(5), one Al(2), two equivalent Al(3), and one Sn(1) atom. Sn(1) is bonded in a 10-coordinate geometry to one Mg(3), three equivalent Mg(2), and six equivalent Al(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg16Al12Sn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.151
_cell_length_b   9.151
_cell_length_c   9.151
_cell_angle_alpha   109.432
_cell_angle_beta   109.432
_cell_angle_gamma   109.432
_symmetry_Int_Tables_number   1
_cell_volume   590.784
_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  0.684  0.684  0.286  1.0
  Mg  Mg1  1  0.398  0.398  0.710  1.0
  Mg  Mg2  1  0.002  0.002  0.002  1.0
  Mg  Mg3  1  0.999  0.999  0.346  1.0
  Mg  Mg4  1  0.599  0.317  0.001  1.0
  Mg  Mg5  1  0.710  0.398  0.398  1.0
  Mg  Mg6  1  0.317  0.001  0.599  1.0
  Mg  Mg7  1  0.346  0.999  0.999  1.0
  Mg  Mg8  1  0.684  0.286  0.684  1.0
  Mg  Mg9  1  0.001  0.599  0.317  1.0
  Mg  Mg10  1  0.599  0.001  0.317  1.0
  Mg  Mg11  1  0.286  0.684  0.684  1.0
  Mg  Mg12  1  0.999  0.346  0.999  1.0
  Mg  Mg13  1  0.001  0.317  0.599  1.0
  Mg  Mg14  1  0.398  0.710  0.398  1.0
  Mg  Mg15  1  0.317  0.599  0.001  1.0
  Al  Al16  1  0.363  0.363  0.176  1.0
  Al  Al17  1  0.184  0.184  0.816  1.0
  Al  Al18  1  0.817  0.632  0.005  1.0
  Al  Al19  1  0.363  0.176  0.363  1.0
  Al  Al20  1  0.005  0.817  0.632  1.0
  Al  Al21  1  0.184  0.816  0.184  1.0
  Al  Al22  1  0.005  0.632  0.817  1.0
  Al  Al23  1  0.632  0.005  0.817  1.0
  Al  Al24  1  0.816  0.184  0.184  1.0
  Al  Al25  1  0.817  0.005  0.632  1.0
  Al  Al26  1  0.176  0.363  0.363  1.0
  Al  Al27  1  0.632  0.817  0.005  1.0
  Sn  Sn28  1  0.666  0.666  0.666  1.0
[/CIF]
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