The material described by Sr4Mg3Al5 is Hexagonal Laves-derived structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 16-coordinate geometry to one Sr(1), three equivalent Sr(2), three equivalent Mg(1), three equivalent Al(1), and six equivalent Al(2) atoms. In the second Sr site, Sr(2) is bonded in a 12-coordinate geometry to three equivalent Sr(1), six equivalent Mg(1), three equivalent Al(1), and three equivalent Al(2) atoms. Mg(1) is bonded to two equivalent Sr(1), four equivalent Sr(2), four equivalent Mg(1), and two equivalent Al(1) atoms to form MgSr6Mg4Al2 cuboctahedra that share corners with four equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, corners with four equivalent Al(1)Sr6Mg3Al3 cuboctahedra, corners with ten equivalent Al(2)Sr6Al6 cuboctahedra, edges with two equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, edges with four equivalent Al(2)Sr6Al6 cuboctahedra, faces with four equivalent Al(2)Sr6Al6 cuboctahedra, faces with six equivalent Al(1)Sr6Mg3Al3 cuboctahedra, and faces with eight equivalent Mg(1)Sr6Mg4Al2 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Sr(1), three equivalent Sr(2), three equivalent Mg(1), and three equivalent Al(2) atoms to form AlSr6Mg3Al3 cuboctahedra that share corners with three equivalent Al(1)Sr6Mg3Al3 cuboctahedra, corners with six equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, corners with six equivalent Al(2)Sr6Al6 cuboctahedra, edges with six equivalent Al(1)Sr6Mg3Al3 cuboctahedra,  a faceface with one Al(1)Sr6Mg3Al3 cuboctahedra, faces with nine equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, and faces with nine equivalent Al(2)Sr6Al6 cuboctahedra. In the second Al site, Al(2) is bonded to two equivalent Sr(2), four equivalent Sr(1), two equivalent Al(1), and four equivalent Al(2) atoms to form distorted AlSr6Al6 cuboctahedra that share corners with four equivalent Al(2)Sr6Al6 cuboctahedra, corners with four equivalent Al(1)Sr6Mg3Al3 cuboctahedra, corners with ten equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, edges with two equivalent Al(2)Sr6Al6 cuboctahedra, edges with four equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, faces with four equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, faces with six equivalent Al(1)Sr6Mg3Al3 cuboctahedra, and faces with eight equivalent Al(2)Sr6Al6 cuboctahedra. is represented by the CIF card [CIF]
data_Sr4Mg3Al5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.045
_cell_length_b   6.045
_cell_length_c   19.955
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   631.590
_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
  Sr  Sr0  1  0.333  0.667  0.661  1.0
  Sr  Sr1  1  0.667  0.333  0.339  1.0
  Sr  Sr2  1  0.667  0.333  0.161  1.0
  Sr  Sr3  1  0.333  0.667  0.839  1.0
  Sr  Sr4  1  0.000  0.000  0.103  1.0
  Sr  Sr5  1  0.000  0.000  0.897  1.0
  Sr  Sr6  1  0.000  0.000  0.603  1.0
  Sr  Sr7  1  0.000  0.000  0.397  1.0
  Mg  Mg8  1  0.500  0.000  0.000  1.0
  Mg  Mg9  1  0.000  0.500  0.000  1.0
  Mg  Mg10  1  0.500  0.000  0.500  1.0
  Mg  Mg11  1  0.500  0.500  0.000  1.0
  Mg  Mg12  1  0.000  0.500  0.500  1.0
  Mg  Mg13  1  0.500  0.500  0.500  1.0
  Al  Al14  1  0.333  0.667  0.140  1.0
  Al  Al15  1  0.667  0.333  0.860  1.0
  Al  Al16  1  0.667  0.333  0.640  1.0
  Al  Al17  1  0.333  0.667  0.360  1.0
  Al  Al18  1  0.165  0.330  0.250  1.0
  Al  Al19  1  0.835  0.670  0.750  1.0
  Al  Al20  1  0.670  0.835  0.250  1.0
  Al  Al21  1  0.330  0.165  0.750  1.0
  Al  Al22  1  0.165  0.835  0.250  1.0
  Al  Al23  1  0.835  0.165  0.750  1.0
[/CIF]
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The material described by Sr4Mg3Al5 is Hexagonal Laves-derived structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 16-coordinate geometry to one Sr(1), three equivalent Sr(2), three equivalent Mg(1), three equivalent Al(1), and six equivalent Al(2) atoms. In the second Sr site, Sr(2) is bonded in a 12-coordinate geometry to three equivalent Sr(1), six equivalent Mg(1), three equivalent Al(1), and three equivalent Al(2) atoms. Mg(1) is bonded to two equivalent Sr(1), four equivalent Sr(2), four equivalent Mg(1), and two equivalent Al(1) atoms to form MgSr6Mg4Al2 cuboctahedra that share corners with four equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, corners with four equivalent Al(1)Sr6Mg3Al3 cuboctahedra, corners with ten equivalent Al(2)Sr6Al6 cuboctahedra, edges with two equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, edges with four equivalent Al(2)Sr6Al6 cuboctahedra, faces with four equivalent Al(2)Sr6Al6 cuboctahedra, faces with six equivalent Al(1)Sr6Mg3Al3 cuboctahedra, and faces with eight equivalent Mg(1)Sr6Mg4Al2 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Sr(1), three equivalent Sr(2), three equivalent Mg(1), and three equivalent Al(2) atoms to form AlSr6Mg3Al3 cuboctahedra that share corners with three equivalent Al(1)Sr6Mg3Al3 cuboctahedra, corners with six equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, corners with six equivalent Al(2)Sr6Al6 cuboctahedra, edges with six equivalent Al(1)Sr6Mg3Al3 cuboctahedra,  a faceface with one Al(1)Sr6Mg3Al3 cuboctahedra, faces with nine equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, and faces with nine equivalent Al(2)Sr6Al6 cuboctahedra. In the second Al site, Al(2) is bonded to two equivalent Sr(2), four equivalent Sr(1), two equivalent Al(1), and four equivalent Al(2) atoms to form distorted AlSr6Al6 cuboctahedra that share corners with four equivalent Al(2)Sr6Al6 cuboctahedra, corners with four equivalent Al(1)Sr6Mg3Al3 cuboctahedra, corners with ten equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, edges with two equivalent Al(2)Sr6Al6 cuboctahedra, edges with four equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, faces with four equivalent Mg(1)Sr6Mg4Al2 cuboctahedra, faces with six equivalent Al(1)Sr6Mg3Al3 cuboctahedra, and faces with eight equivalent Al(2)Sr6Al6 cuboctahedra. is represented by the CIF card [CIF]
data_Sr4Mg3Al5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.045
_cell_length_b   6.045
_cell_length_c   19.955
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   631.590
_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
  Sr  Sr0  1  0.333  0.667  0.661  1.0
  Sr  Sr1  1  0.667  0.333  0.339  1.0
  Sr  Sr2  1  0.667  0.333  0.161  1.0
  Sr  Sr3  1  0.333  0.667  0.839  1.0
  Sr  Sr4  1  0.000  0.000  0.103  1.0
  Sr  Sr5  1  0.000  0.000  0.897  1.0
  Sr  Sr6  1  0.000  0.000  0.603  1.0
  Sr  Sr7  1  0.000  0.000  0.397  1.0
  Mg  Mg8  1  0.500  0.000  0.000  1.0
  Mg  Mg9  1  0.000  0.500  0.000  1.0
  Mg  Mg10  1  0.500  0.000  0.500  1.0
  Mg  Mg11  1  0.500  0.500  0.000  1.0
  Mg  Mg12  1  0.000  0.500  0.500  1.0
  Mg  Mg13  1  0.500  0.500  0.500  1.0
  Al  Al14  1  0.333  0.667  0.140  1.0
  Al  Al15  1  0.667  0.333  0.860  1.0
  Al  Al16  1  0.667  0.333  0.640  1.0
  Al  Al17  1  0.333  0.667  0.360  1.0
  Al  Al18  1  0.165  0.330  0.250  1.0
  Al  Al19  1  0.835  0.670  0.750  1.0
  Al  Al20  1  0.670  0.835  0.250  1.0
  Al  Al21  1  0.330  0.165  0.750  1.0
  Al  Al22  1  0.165  0.835  0.250  1.0
  Al  Al23  1  0.835  0.165  0.750  1.0
[/CIF]
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