The compound described by Mg17PtAl11 is gamma-brass-derived structured and crystallizes in the monoclinic Cm space group. There are eleven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 1-coordinate geometry to one Mg(4), two equivalent Mg(10), two equivalent Mg(6), one Pt(1), two equivalent Al(2), and two equivalent Al(4) atoms. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to one Mg(3), two equivalent Mg(11), two equivalent Mg(6), two equivalent Mg(8), one Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the third Mg site, Mg(3) is bonded in a 10-coordinate geometry to one Mg(2), one Mg(5), two equivalent Mg(7), two equivalent Al(2), two equivalent Al(4), and two equivalent Al(5) atoms. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to one Mg(1), one Mg(5), two equivalent Mg(8), two equivalent Al(2), two equivalent Al(3), and two equivalent Al(6) atoms. In the fifth Mg site, Mg(5) is bonded in a 16-coordinate geometry to one Mg(3), one Mg(4), two equivalent Mg(9), one Pt(1), one Al(1), two equivalent Al(2), two equivalent Al(3), two equivalent Al(4), two equivalent Al(5), and two equivalent Al(6) atoms. In the sixth Mg site, Mg(6) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(10), one Mg(11), one Mg(2), one Mg(7), one Mg(8), one Mg(9), one Pt(1), one Al(1), one Al(2), one Al(5), and one Al(6) atom. In the seventh Mg site, Mg(7) is bonded in a 3-coordinate geometry to one Mg(11), one Mg(3), one Mg(6), one Mg(8), two equivalent Mg(10), one Pt(1), one Al(3), one Al(4), one Al(5), and one Al(6) atom. In the eighth Mg site, Mg(8) is bonded in a 12-coordinate geometry to one Mg(10), one Mg(2), one Mg(4), one Mg(6), one Mg(7), two equivalent Mg(11), one Al(1), one Al(3), one Al(4), one Al(5), and one Al(6) atom. In the ninth Mg site, Mg(9) is bonded in a 10-coordinate geometry to one Mg(10), one Mg(11), one Mg(5), one Mg(6), one Pt(1), one Al(1), one Al(3), one Al(4), one Al(5), and one Al(6) atom. In the tenth Mg site, Mg(10) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(11), one Mg(6), one Mg(8), one Mg(9), two equivalent Mg(7), one Al(2), one Al(3), one Al(4), and two equivalent Al(6) atoms. In the eleventh Mg site, Mg(11) is bonded in a 12-coordinate geometry to one Mg(10), one Mg(2), one Mg(6), one Mg(7), one Mg(9), two equivalent Mg(8), one Al(2), one Al(3), one Al(4), and two equivalent Al(5) atoms. Pt(1) is bonded in a 11-coordinate geometry to one Mg(1), one Mg(5), two equivalent Mg(6), two equivalent Mg(7), two equivalent Mg(9), one Al(1), and two equivalent Al(3) atoms. There are six inequivalent Al sites. In the first Al site, Al(1) is bonded in a 11-coordinate geometry to one Mg(2), one Mg(5), two equivalent Mg(6), two equivalent Mg(8), two equivalent Mg(9), one Pt(1), and two equivalent Al(4) atoms. In the second Al site, Al(2) is bonded in a 11-coordinate geometry to one Mg(1), one Mg(10), one Mg(11), one Mg(2), one Mg(3), one Mg(4), one Mg(5), one Mg(6), one Al(2), one Al(5), and one Al(6) atom. In the third Al site, Al(3) is bonded in a 11-coordinate geometry to one Mg(10), one Mg(11), one Mg(2), one Mg(4), one Mg(5), one Mg(7), one Mg(8), one Mg(9), one Pt(1), one Al(3), and one Al(6) atom. In the fourth Al site, Al(4) is bonded in a 11-coordinate geometry to one Mg(1), one Mg(10), one Mg(11), one Mg(3), one Mg(5), one Mg(7), one Mg(8), one Mg(9), one Al(1), one Al(4), and one Al(5) atom. In the fifth Al site, Al(5) is bonded in a 11-coordinate geometry to one Mg(3), one Mg(5), one Mg(6), one Mg(7), one Mg(8), one Mg(9), two equivalent Mg(11), one Al(2), one Al(4), and one Al(6) atom. In the sixth Al site, Al(6) is bonded in a 11-coordinate geometry to one Mg(4), one Mg(5), one Mg(6), one Mg(7), one Mg(8), one Mg(9), two equivalent Mg(10), one Al(2), one Al(3), and one Al(5) atom. is represented by the CIF file [CIF]
data_Mg17Al11Pt
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.079
_cell_length_b   8.986
_cell_length_c   9.081
_cell_angle_alpha   109.459
_cell_angle_beta   109.870
_cell_angle_gamma   108.865
_symmetry_Int_Tables_number   1
_cell_volume   571.803
_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  0.610  0.326  0.000  1.0
  Mg  Mg1  1  0.314  0.607  0.000  1.0
  Mg  Mg2  1  0.999  0.347  0.000  1.0
  Mg  Mg3  1  0.347  0.003  0.000  1.0
  Mg  Mg4  1  0.998  0.994  0.000  1.0
  Mg  Mg5  1  0.684  0.682  0.278  1.0
  Mg  Mg6  1  0.994  0.604  0.309  1.0
  Mg  Mg7  1  0.601  0.000  0.317  1.0
  Mg  Mg8  1  0.997  0.993  0.338  1.0
  Mg  Mg9  1  0.714  0.398  0.397  1.0
  Mg  Mg10  1  0.399  0.714  0.398  1.0
  Mg  Mg11  1  0.001  0.316  0.602  1.0
  Mg  Mg12  1  0.317  0.001  0.603  1.0
  Mg  Mg13  1  0.659  0.655  0.662  1.0
  Mg  Mg14  1  0.285  0.683  0.683  1.0
  Mg  Mg15  1  0.685  0.295  0.691  1.0
  Mg  Mg16  1  0.406  0.404  0.722  1.0
  Al  Al17  1  0.637  0.806  0.000  1.0
  Al  Al18  1  0.366  0.367  0.180  1.0
  Al  Al19  1  0.175  0.813  0.182  1.0
  Al  Al20  1  0.818  0.182  0.185  1.0
  Al  Al21  1  0.181  0.365  0.366  1.0
  Al  Al22  1  0.367  0.179  0.366  1.0
  Al  Al23  1  0.001  0.813  0.634  1.0
  Al  Al24  1  0.816  1.000  0.634  1.0
  Al  Al25  1  0.633  0.998  0.815  1.0
  Al  Al26  1  0.993  0.631  0.818  1.0
  Al  Al27  1  0.186  0.187  0.820  1.0
  Pt  Pt28  1  0.816  0.637  0.000  1.0
[/CIF]
.
The compound described by Mg17PtAl11 is gamma-brass-derived structured and crystallizes in the monoclinic Cm space group. There are eleven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 1-coordinate geometry to one Mg(4), two equivalent Mg(10), two equivalent Mg(6), one Pt(1), two equivalent Al(2), and two equivalent Al(4) atoms. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to one Mg(3), two equivalent Mg(11), two equivalent Mg(6), two equivalent Mg(8), one Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the third Mg site, Mg(3) is bonded in a 10-coordinate geometry to one Mg(2), one Mg(5), two equivalent Mg(7), two equivalent Al(2), two equivalent Al(4), and two equivalent Al(5) atoms. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to one Mg(1), one Mg(5), two equivalent Mg(8), two equivalent Al(2), two equivalent Al(3), and two equivalent Al(6) atoms. In the fifth Mg site, Mg(5) is bonded in a 16-coordinate geometry to one Mg(3), one Mg(4), two equivalent Mg(9), one Pt(1), one Al(1), two equivalent Al(2), two equivalent Al(3), two equivalent Al(4), two equivalent Al(5), and two equivalent Al(6) atoms. In the sixth Mg site, Mg(6) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(10), one Mg(11), one Mg(2), one Mg(7), one Mg(8), one Mg(9), one Pt(1), one Al(1), one Al(2), one Al(5), and one Al(6) atom. In the seventh Mg site, Mg(7) is bonded in a 3-coordinate geometry to one Mg(11), one Mg(3), one Mg(6), one Mg(8), two equivalent Mg(10), one Pt(1), one Al(3), one Al(4), one Al(5), and one Al(6) atom. In the eighth Mg site, Mg(8) is bonded in a 12-coordinate geometry to one Mg(10), one Mg(2), one Mg(4), one Mg(6), one Mg(7), two equivalent Mg(11), one Al(1), one Al(3), one Al(4), one Al(5), and one Al(6) atom. In the ninth Mg site, Mg(9) is bonded in a 10-coordinate geometry to one Mg(10), one Mg(11), one Mg(5), one Mg(6), one Pt(1), one Al(1), one Al(3), one Al(4), one Al(5), and one Al(6) atom. In the tenth Mg site, Mg(10) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(11), one Mg(6), one Mg(8), one Mg(9), two equivalent Mg(7), one Al(2), one Al(3), one Al(4), and two equivalent Al(6) atoms. In the eleventh Mg site, Mg(11) is bonded in a 12-coordinate geometry to one Mg(10), one Mg(2), one Mg(6), one Mg(7), one Mg(9), two equivalent Mg(8), one Al(2), one Al(3), one Al(4), and two equivalent Al(5) atoms. Pt(1) is bonded in a 11-coordinate geometry to one Mg(1), one Mg(5), two equivalent Mg(6), two equivalent Mg(7), two equivalent Mg(9), one Al(1), and two equivalent Al(3) atoms. There are six inequivalent Al sites. In the first Al site, Al(1) is bonded in a 11-coordinate geometry to one Mg(2), one Mg(5), two equivalent Mg(6), two equivalent Mg(8), two equivalent Mg(9), one Pt(1), and two equivalent Al(4) atoms. In the second Al site, Al(2) is bonded in a 11-coordinate geometry to one Mg(1), one Mg(10), one Mg(11), one Mg(2), one Mg(3), one Mg(4), one Mg(5), one Mg(6), one Al(2), one Al(5), and one Al(6) atom. In the third Al site, Al(3) is bonded in a 11-coordinate geometry to one Mg(10), one Mg(11), one Mg(2), one Mg(4), one Mg(5), one Mg(7), one Mg(8), one Mg(9), one Pt(1), one Al(3), and one Al(6) atom. In the fourth Al site, Al(4) is bonded in a 11-coordinate geometry to one Mg(1), one Mg(10), one Mg(11), one Mg(3), one Mg(5), one Mg(7), one Mg(8), one Mg(9), one Al(1), one Al(4), and one Al(5) atom. In the fifth Al site, Al(5) is bonded in a 11-coordinate geometry to one Mg(3), one Mg(5), one Mg(6), one Mg(7), one Mg(8), one Mg(9), two equivalent Mg(11), one Al(2), one Al(4), and one Al(6) atom. In the sixth Al site, Al(6) is bonded in a 11-coordinate geometry to one Mg(4), one Mg(5), one Mg(6), one Mg(7), one Mg(8), one Mg(9), two equivalent Mg(10), one Al(2), one Al(3), and one Al(5) atom. is represented by the CIF file [CIF]
data_Mg17Al11Pt
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.079
_cell_length_b   8.986
_cell_length_c   9.081
_cell_angle_alpha   109.459
_cell_angle_beta   109.870
_cell_angle_gamma   108.865
_symmetry_Int_Tables_number   1
_cell_volume   571.803
_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  0.610  0.326  0.000  1.0
  Mg  Mg1  1  0.314  0.607  0.000  1.0
  Mg  Mg2  1  0.999  0.347  0.000  1.0
  Mg  Mg3  1  0.347  0.003  0.000  1.0
  Mg  Mg4  1  0.998  0.994  0.000  1.0
  Mg  Mg5  1  0.684  0.682  0.278  1.0
  Mg  Mg6  1  0.994  0.604  0.309  1.0
  Mg  Mg7  1  0.601  0.000  0.317  1.0
  Mg  Mg8  1  0.997  0.993  0.338  1.0
  Mg  Mg9  1  0.714  0.398  0.397  1.0
  Mg  Mg10  1  0.399  0.714  0.398  1.0
  Mg  Mg11  1  0.001  0.316  0.602  1.0
  Mg  Mg12  1  0.317  0.001  0.603  1.0
  Mg  Mg13  1  0.659  0.655  0.662  1.0
  Mg  Mg14  1  0.285  0.683  0.683  1.0
  Mg  Mg15  1  0.685  0.295  0.691  1.0
  Mg  Mg16  1  0.406  0.404  0.722  1.0
  Al  Al17  1  0.637  0.806  0.000  1.0
  Al  Al18  1  0.366  0.367  0.180  1.0
  Al  Al19  1  0.175  0.813  0.182  1.0
  Al  Al20  1  0.818  0.182  0.185  1.0
  Al  Al21  1  0.181  0.365  0.366  1.0
  Al  Al22  1  0.367  0.179  0.366  1.0
  Al  Al23  1  0.001  0.813  0.634  1.0
  Al  Al24  1  0.816  1.000  0.634  1.0
  Al  Al25  1  0.633  0.998  0.815  1.0
  Al  Al26  1  0.993  0.631  0.818  1.0
  Al  Al27  1  0.186  0.187  0.820  1.0
  Pt  Pt28  1  0.816  0.637  0.000  1.0
[/CIF]
.