The material described by Ba7Al4Sb9 crystallizes in the orthorhombic Pmmn space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 7-coordinate geometry to one Al(1), two equivalent Sb(2), and four equivalent Sb(1) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one Al(1), one Sb(3), one Sb(4), one Sb(5), two equivalent Sb(1), and two equivalent Sb(2) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to two equivalent Al(1), two equivalent Al(2), two equivalent Sb(5), and four equivalent Sb(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one Ba(1), one Ba(3), two equivalent Ba(2), one Sb(2), one Sb(5), and two equivalent Sb(1) atoms to form distorted AlBa4Sb4 tetrahedra that share  an edgeedge with one Al(1)Ba4Sb4 tetrahedra and edges with two equivalent Al(2)BaSb4 tetrahedra. In the second Al site, Al(2) is bonded to one Ba(3), one Sb(3), one Sb(4), and two equivalent Sb(1) atoms to form distorted AlBaSb4 tetrahedra that share  a cornercorner with one Al(2)BaSb4 tetrahedra,  an edgeedge with one Al(2)BaSb4 tetrahedra, and edges with two equivalent Al(1)Ba4Sb4 tetrahedra. There are five inequivalent Sb sites. In the first Sb site, Sb(3) is bonded in a 2-coordinate geometry to four equivalent Ba(2) and two equivalent Al(2) atoms. In the second Sb site, Sb(4) is bonded in a 6-coordinate geometry to four equivalent Ba(2) and two equivalent Al(2) atoms. In the third Sb site, Sb(5) is bonded in a 3-coordinate geometry to two equivalent Ba(3), four equivalent Ba(2), and two equivalent Al(1) atoms. In the fourth Sb site, Sb(1) is bonded in a 7-coordinate geometry to one Ba(3), two equivalent Ba(1), two equivalent Ba(2), one Al(1), and one Al(2) atom. In the fifth Sb site, Sb(2) is bonded in a 7-coordinate geometry to two equivalent Ba(1), four equivalent Ba(2), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba7Al4Sb9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.270
_cell_length_b   10.895
_cell_length_c   18.382
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1456.020
_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
  Ba  Ba0  1  0.454  0.500  0.784  1.0
  Ba  Ba1  1  0.454  0.500  0.216  1.0
  Ba  Ba2  1  0.546  0.000  0.716  1.0
  Ba  Ba3  1  0.546  0.000  0.284  1.0
  Ba  Ba4  1  0.952  0.275  0.876  1.0
  Ba  Ba5  1  0.952  0.725  0.876  1.0
  Ba  Ba6  1  0.952  0.275  0.124  1.0
  Ba  Ba7  1  0.952  0.725  0.124  1.0
  Ba  Ba8  1  0.048  0.225  0.624  1.0
  Ba  Ba9  1  0.048  0.775  0.624  1.0
  Ba  Ba10  1  0.048  0.225  0.376  1.0
  Ba  Ba11  1  0.048  0.775  0.376  1.0
  Ba  Ba12  1  0.410  0.500  0.500  1.0
  Ba  Ba13  1  0.590  0.000  0.000  1.0
  Al  Al14  1  0.759  0.500  0.374  1.0
  Al  Al15  1  0.759  0.500  0.626  1.0
  Al  Al16  1  0.241  0.000  0.126  1.0
  Al  Al17  1  0.241  0.000  0.874  1.0
  Al  Al18  1  0.561  0.824  0.500  1.0
  Al  Al19  1  0.561  0.176  0.500  1.0
  Al  Al20  1  0.439  0.676  0.000  1.0
  Al  Al21  1  0.439  0.324  0.000  1.0
  Sb  Sb22  1  0.549  0.291  0.370  1.0
  Sb  Sb23  1  0.549  0.709  0.370  1.0
  Sb  Sb24  1  0.549  0.291  0.630  1.0
  Sb  Sb25  1  0.549  0.709  0.630  1.0
  Sb  Sb26  1  0.451  0.209  0.130  1.0
  Sb  Sb27  1  0.451  0.791  0.130  1.0
  Sb  Sb28  1  0.451  0.209  0.870  1.0
  Sb  Sb29  1  0.451  0.791  0.870  1.0
  Sb  Sb30  1  0.977  0.500  0.260  1.0
  Sb  Sb31  1  0.977  0.500  0.740  1.0
  Sb  Sb32  1  0.023  0.000  0.240  1.0
  Sb  Sb33  1  0.023  0.000  0.760  1.0
  Sb  Sb34  1  0.707  0.500  0.000  1.0
  Sb  Sb35  1  0.293  0.000  0.500  1.0
  Sb  Sb36  1  0.169  0.500  0.000  1.0
  Sb  Sb37  1  0.831  0.000  0.500  1.0
  Sb  Sb38  1  0.950  0.500  0.500  1.0
  Sb  Sb39  1  0.050  0.000  0.000  1.0
[/CIF]
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The material described by Ba7Al4Sb9 crystallizes in the orthorhombic Pmmn space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 7-coordinate geometry to one Al(1), two equivalent Sb(2), and four equivalent Sb(1) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one Al(1), one Sb(3), one Sb(4), one Sb(5), two equivalent Sb(1), and two equivalent Sb(2) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to two equivalent Al(1), two equivalent Al(2), two equivalent Sb(5), and four equivalent Sb(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one Ba(1), one Ba(3), two equivalent Ba(2), one Sb(2), one Sb(5), and two equivalent Sb(1) atoms to form distorted AlBa4Sb4 tetrahedra that share  an edgeedge with one Al(1)Ba4Sb4 tetrahedra and edges with two equivalent Al(2)BaSb4 tetrahedra. In the second Al site, Al(2) is bonded to one Ba(3), one Sb(3), one Sb(4), and two equivalent Sb(1) atoms to form distorted AlBaSb4 tetrahedra that share  a cornercorner with one Al(2)BaSb4 tetrahedra,  an edgeedge with one Al(2)BaSb4 tetrahedra, and edges with two equivalent Al(1)Ba4Sb4 tetrahedra. There are five inequivalent Sb sites. In the first Sb site, Sb(3) is bonded in a 2-coordinate geometry to four equivalent Ba(2) and two equivalent Al(2) atoms. In the second Sb site, Sb(4) is bonded in a 6-coordinate geometry to four equivalent Ba(2) and two equivalent Al(2) atoms. In the third Sb site, Sb(5) is bonded in a 3-coordinate geometry to two equivalent Ba(3), four equivalent Ba(2), and two equivalent Al(1) atoms. In the fourth Sb site, Sb(1) is bonded in a 7-coordinate geometry to one Ba(3), two equivalent Ba(1), two equivalent Ba(2), one Al(1), and one Al(2) atom. In the fifth Sb site, Sb(2) is bonded in a 7-coordinate geometry to two equivalent Ba(1), four equivalent Ba(2), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba7Al4Sb9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.270
_cell_length_b   10.895
_cell_length_c   18.382
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1456.020
_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
  Ba  Ba0  1  0.454  0.500  0.784  1.0
  Ba  Ba1  1  0.454  0.500  0.216  1.0
  Ba  Ba2  1  0.546  0.000  0.716  1.0
  Ba  Ba3  1  0.546  0.000  0.284  1.0
  Ba  Ba4  1  0.952  0.275  0.876  1.0
  Ba  Ba5  1  0.952  0.725  0.876  1.0
  Ba  Ba6  1  0.952  0.275  0.124  1.0
  Ba  Ba7  1  0.952  0.725  0.124  1.0
  Ba  Ba8  1  0.048  0.225  0.624  1.0
  Ba  Ba9  1  0.048  0.775  0.624  1.0
  Ba  Ba10  1  0.048  0.225  0.376  1.0
  Ba  Ba11  1  0.048  0.775  0.376  1.0
  Ba  Ba12  1  0.410  0.500  0.500  1.0
  Ba  Ba13  1  0.590  0.000  0.000  1.0
  Al  Al14  1  0.759  0.500  0.374  1.0
  Al  Al15  1  0.759  0.500  0.626  1.0
  Al  Al16  1  0.241  0.000  0.126  1.0
  Al  Al17  1  0.241  0.000  0.874  1.0
  Al  Al18  1  0.561  0.824  0.500  1.0
  Al  Al19  1  0.561  0.176  0.500  1.0
  Al  Al20  1  0.439  0.676  0.000  1.0
  Al  Al21  1  0.439  0.324  0.000  1.0
  Sb  Sb22  1  0.549  0.291  0.370  1.0
  Sb  Sb23  1  0.549  0.709  0.370  1.0
  Sb  Sb24  1  0.549  0.291  0.630  1.0
  Sb  Sb25  1  0.549  0.709  0.630  1.0
  Sb  Sb26  1  0.451  0.209  0.130  1.0
  Sb  Sb27  1  0.451  0.791  0.130  1.0
  Sb  Sb28  1  0.451  0.209  0.870  1.0
  Sb  Sb29  1  0.451  0.791  0.870  1.0
  Sb  Sb30  1  0.977  0.500  0.260  1.0
  Sb  Sb31  1  0.977  0.500  0.740  1.0
  Sb  Sb32  1  0.023  0.000  0.240  1.0
  Sb  Sb33  1  0.023  0.000  0.760  1.0
  Sb  Sb34  1  0.707  0.500  0.000  1.0
  Sb  Sb35  1  0.293  0.000  0.500  1.0
  Sb  Sb36  1  0.169  0.500  0.000  1.0
  Sb  Sb37  1  0.831  0.000  0.500  1.0
  Sb  Sb38  1  0.950  0.500  0.500  1.0
  Sb  Sb39  1  0.050  0.000  0.000  1.0
[/CIF]
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