The material structure described by Sr5Al2Sb6 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one Al(2), one Sb(1), one Sb(2), one Sb(4), two equivalent Sb(3), and two equivalent Sb(5) atoms. In the second Sr site, Sr(2) is bonded to one Sb(4), two equivalent Sb(1), two equivalent Sb(2), and two equivalent Sb(3) atoms to form distorted SrSb7 pentagonal bipyramids that share corners with three equivalent Al(1)Sb4 tetrahedra, corners with three equivalent Al(2)Sr2Sb4 tetrahedra, edges with two equivalent Sr(2)Sb7 pentagonal bipyramids, and  an edgeedge with one Al(1)Sb4 tetrahedra. In the third Sr site, Sr(3) is bonded in a 6-coordinate geometry to one Sb(1), one Sb(3), one Sb(4), one Sb(5), and two equivalent Sb(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one Sb(1), one Sb(4), and two equivalent Sb(2) atoms to form AlSb4 tetrahedra that share corners with three equivalent Sr(2)Sb7 pentagonal bipyramids,  a cornercorner with one Al(2)Sr2Sb4 tetrahedra,  an edgeedge with one Sr(2)Sb7 pentagonal bipyramid, and  an edgeedge with one Al(2)Sr2Sb4 tetrahedra. In the second Al site, Al(2) is bonded to two equivalent Sr(1), one Sb(4), one Sb(5), and two equivalent Sb(2) atoms to form distorted AlSr2Sb4 tetrahedra that share corners with three equivalent Sr(2)Sb7 pentagonal bipyramids,  a cornercorner with one Al(1)Sb4 tetrahedra, and  an edgeedge with one Al(1)Sb4 tetrahedra. There are five inequivalent Sb sites. In the first Sb site, Sb(4) is bonded in a 7-coordinate geometry to one Sr(2), two equivalent Sr(1), two equivalent Sr(3), one Al(1), and one Al(2) atom. In the second Sb site, Sb(5) is bonded in a 8-coordinate geometry to two equivalent Sr(3), four equivalent Sr(1), one Al(2), and one Sb(3) atom. In the third Sb site, Sb(1) is bonded in a 7-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), two equivalent Sr(3), and one Al(1) atom. In the fourth Sb site, Sb(2) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), two equivalent Sr(3), one Al(1), and one Al(2) atom. In the fifth Sb site, Sb(3) is bonded in a 9-coordinate geometry to two equivalent Sr(2), two equivalent Sr(3), four equivalent Sr(1), and one Sb(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr5(AlSb3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.420
_cell_length_b   12.217
_cell_length_c   13.516
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1720.642
_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
  Sr  Sr0  1  0.978  0.830  0.465  1.0
  Sr  Sr1  1  0.250  0.162  0.814  1.0
  Sr  Sr2  1  0.478  0.670  0.965  1.0
  Sr  Sr3  1  0.522  0.330  0.035  1.0
  Sr  Sr4  1  0.474  0.580  0.263  1.0
  Sr  Sr5  1  0.526  0.920  0.763  1.0
  Sr  Sr6  1  0.750  0.338  0.314  1.0
  Sr  Sr7  1  0.478  0.170  0.535  1.0
  Sr  Sr8  1  0.026  0.080  0.237  1.0
  Sr  Sr9  1  0.026  0.580  0.263  1.0
  Sr  Sr10  1  0.526  0.420  0.737  1.0
  Sr  Sr11  1  0.750  0.838  0.186  1.0
  Sr  Sr12  1  0.978  0.330  0.035  1.0
  Sr  Sr13  1  0.522  0.830  0.465  1.0
  Sr  Sr14  1  0.022  0.670  0.965  1.0
  Sr  Sr15  1  0.474  0.080  0.237  1.0
  Sr  Sr16  1  0.974  0.420  0.737  1.0
  Sr  Sr17  1  0.974  0.920  0.763  1.0
  Sr  Sr18  1  0.250  0.662  0.686  1.0
  Sr  Sr19  1  0.022  0.170  0.535  1.0
  Al  Al20  1  0.750  0.579  0.567  1.0
  Al  Al21  1  0.250  0.421  0.433  1.0
  Al  Al22  1  0.250  0.810  0.300  1.0
  Al  Al23  1  0.750  0.190  0.700  1.0
  Al  Al24  1  0.250  0.921  0.067  1.0
  Al  Al25  1  0.750  0.690  0.800  1.0
  Al  Al26  1  0.750  0.079  0.933  1.0
  Al  Al27  1  0.250  0.310  0.200  1.0
  Sb  Sb28  1  0.750  0.645  0.379  1.0
  Sb  Sb29  1  0.057  0.827  0.171  1.0
  Sb  Sb30  1  0.943  0.673  0.671  1.0
  Sb  Sb31  1  0.250  0.954  0.621  1.0
  Sb  Sb32  1  0.057  0.327  0.329  1.0
  Sb  Sb33  1  0.250  0.648  0.436  1.0
  Sb  Sb34  1  0.443  0.327  0.329  1.0
  Sb  Sb35  1  0.557  0.173  0.829  1.0
  Sb  Sb36  1  0.250  0.500  0.090  1.0
  Sb  Sb37  1  0.750  0.352  0.564  1.0
  Sb  Sb38  1  0.250  0.148  0.064  1.0
  Sb  Sb39  1  0.250  0.454  0.879  1.0
  Sb  Sb40  1  0.557  0.673  0.671  1.0
  Sb  Sb41  1  0.250  0.355  0.621  1.0
  Sb  Sb42  1  0.750  0.145  0.121  1.0
  Sb  Sb43  1  0.943  0.173  0.829  1.0
  Sb  Sb44  1  0.750  0.000  0.590  1.0
  Sb  Sb45  1  0.750  0.046  0.379  1.0
  Sb  Sb46  1  0.750  0.546  0.121  1.0
  Sb  Sb47  1  0.750  0.500  0.910  1.0
  Sb  Sb48  1  0.250  1.000  0.410  1.0
  Sb  Sb49  1  0.750  0.852  0.936  1.0
  Sb  Sb50  1  0.443  0.827  0.171  1.0
  Sb  Sb51  1  0.250  0.855  0.879  1.0
[/CIF]
.
The material structure described by Sr5Al2Sb6 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one Al(2), one Sb(1), one Sb(2), one Sb(4), two equivalent Sb(3), and two equivalent Sb(5) atoms. In the second Sr site, Sr(2) is bonded to one Sb(4), two equivalent Sb(1), two equivalent Sb(2), and two equivalent Sb(3) atoms to form distorted SrSb7 pentagonal bipyramids that share corners with three equivalent Al(1)Sb4 tetrahedra, corners with three equivalent Al(2)Sr2Sb4 tetrahedra, edges with two equivalent Sr(2)Sb7 pentagonal bipyramids, and  an edgeedge with one Al(1)Sb4 tetrahedra. In the third Sr site, Sr(3) is bonded in a 6-coordinate geometry to one Sb(1), one Sb(3), one Sb(4), one Sb(5), and two equivalent Sb(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one Sb(1), one Sb(4), and two equivalent Sb(2) atoms to form AlSb4 tetrahedra that share corners with three equivalent Sr(2)Sb7 pentagonal bipyramids,  a cornercorner with one Al(2)Sr2Sb4 tetrahedra,  an edgeedge with one Sr(2)Sb7 pentagonal bipyramid, and  an edgeedge with one Al(2)Sr2Sb4 tetrahedra. In the second Al site, Al(2) is bonded to two equivalent Sr(1), one Sb(4), one Sb(5), and two equivalent Sb(2) atoms to form distorted AlSr2Sb4 tetrahedra that share corners with three equivalent Sr(2)Sb7 pentagonal bipyramids,  a cornercorner with one Al(1)Sb4 tetrahedra, and  an edgeedge with one Al(1)Sb4 tetrahedra. There are five inequivalent Sb sites. In the first Sb site, Sb(4) is bonded in a 7-coordinate geometry to one Sr(2), two equivalent Sr(1), two equivalent Sr(3), one Al(1), and one Al(2) atom. In the second Sb site, Sb(5) is bonded in a 8-coordinate geometry to two equivalent Sr(3), four equivalent Sr(1), one Al(2), and one Sb(3) atom. In the third Sb site, Sb(1) is bonded in a 7-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), two equivalent Sr(3), and one Al(1) atom. In the fourth Sb site, Sb(2) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), two equivalent Sr(3), one Al(1), and one Al(2) atom. In the fifth Sb site, Sb(3) is bonded in a 9-coordinate geometry to two equivalent Sr(2), two equivalent Sr(3), four equivalent Sr(1), and one Sb(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr5(AlSb3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.420
_cell_length_b   12.217
_cell_length_c   13.516
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1720.642
_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
  Sr  Sr0  1  0.978  0.830  0.465  1.0
  Sr  Sr1  1  0.250  0.162  0.814  1.0
  Sr  Sr2  1  0.478  0.670  0.965  1.0
  Sr  Sr3  1  0.522  0.330  0.035  1.0
  Sr  Sr4  1  0.474  0.580  0.263  1.0
  Sr  Sr5  1  0.526  0.920  0.763  1.0
  Sr  Sr6  1  0.750  0.338  0.314  1.0
  Sr  Sr7  1  0.478  0.170  0.535  1.0
  Sr  Sr8  1  0.026  0.080  0.237  1.0
  Sr  Sr9  1  0.026  0.580  0.263  1.0
  Sr  Sr10  1  0.526  0.420  0.737  1.0
  Sr  Sr11  1  0.750  0.838  0.186  1.0
  Sr  Sr12  1  0.978  0.330  0.035  1.0
  Sr  Sr13  1  0.522  0.830  0.465  1.0
  Sr  Sr14  1  0.022  0.670  0.965  1.0
  Sr  Sr15  1  0.474  0.080  0.237  1.0
  Sr  Sr16  1  0.974  0.420  0.737  1.0
  Sr  Sr17  1  0.974  0.920  0.763  1.0
  Sr  Sr18  1  0.250  0.662  0.686  1.0
  Sr  Sr19  1  0.022  0.170  0.535  1.0
  Al  Al20  1  0.750  0.579  0.567  1.0
  Al  Al21  1  0.250  0.421  0.433  1.0
  Al  Al22  1  0.250  0.810  0.300  1.0
  Al  Al23  1  0.750  0.190  0.700  1.0
  Al  Al24  1  0.250  0.921  0.067  1.0
  Al  Al25  1  0.750  0.690  0.800  1.0
  Al  Al26  1  0.750  0.079  0.933  1.0
  Al  Al27  1  0.250  0.310  0.200  1.0
  Sb  Sb28  1  0.750  0.645  0.379  1.0
  Sb  Sb29  1  0.057  0.827  0.171  1.0
  Sb  Sb30  1  0.943  0.673  0.671  1.0
  Sb  Sb31  1  0.250  0.954  0.621  1.0
  Sb  Sb32  1  0.057  0.327  0.329  1.0
  Sb  Sb33  1  0.250  0.648  0.436  1.0
  Sb  Sb34  1  0.443  0.327  0.329  1.0
  Sb  Sb35  1  0.557  0.173  0.829  1.0
  Sb  Sb36  1  0.250  0.500  0.090  1.0
  Sb  Sb37  1  0.750  0.352  0.564  1.0
  Sb  Sb38  1  0.250  0.148  0.064  1.0
  Sb  Sb39  1  0.250  0.454  0.879  1.0
  Sb  Sb40  1  0.557  0.673  0.671  1.0
  Sb  Sb41  1  0.250  0.355  0.621  1.0
  Sb  Sb42  1  0.750  0.145  0.121  1.0
  Sb  Sb43  1  0.943  0.173  0.829  1.0
  Sb  Sb44  1  0.750  0.000  0.590  1.0
  Sb  Sb45  1  0.750  0.046  0.379  1.0
  Sb  Sb46  1  0.750  0.546  0.121  1.0
  Sb  Sb47  1  0.750  0.500  0.910  1.0
  Sb  Sb48  1  0.250  1.000  0.410  1.0
  Sb  Sb49  1  0.750  0.852  0.936  1.0
  Sb  Sb50  1  0.443  0.827  0.171  1.0
  Sb  Sb51  1  0.250  0.855  0.879  1.0
[/CIF]
.