The structure described by Ba3(AlSi)2 crystallizes in the orthorhombic Immm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to eight equivalent Al(1) and four equivalent Si(1) atoms to form a mixture of edge and face-sharing BaAl8Si4 cuboctahedra. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to two equivalent Al(1) and five equivalent Si(1) atoms. Al(1) is bonded in a 9-coordinate geometry to two equivalent Ba(2), four equivalent Ba(1), one Al(1), and two equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Ba(1), five equivalent Ba(2), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3(AlSi)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.320
_cell_length_b   5.168
_cell_length_c   10.533
_cell_angle_alpha   104.203
_cell_angle_beta   101.834
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   222.819
_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
  Ba  Ba0  1  0.500  0.000  0.000  1.0
  Ba  Ba1  1  0.815  0.815  0.631  1.0
  Ba  Ba2  1  0.185  0.185  0.369  1.0
  Al  Al3  1  0.065  0.565  0.130  1.0
  Al  Al4  1  0.935  0.435  0.870  1.0
  Si  Si5  1  0.633  0.632  0.266  1.0
  Si  Si6  1  0.367  0.368  0.734  1.0
[/CIF]
.
The structure described by Ba3(AlSi)2 crystallizes in the orthorhombic Immm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to eight equivalent Al(1) and four equivalent Si(1) atoms to form a mixture of edge and face-sharing BaAl8Si4 cuboctahedra. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to two equivalent Al(1) and five equivalent Si(1) atoms. Al(1) is bonded in a 9-coordinate geometry to two equivalent Ba(2), four equivalent Ba(1), one Al(1), and two equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Ba(1), five equivalent Ba(2), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3(AlSi)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.320
_cell_length_b   5.168
_cell_length_c   10.533
_cell_angle_alpha   104.203
_cell_angle_beta   101.834
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   222.819
_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
  Ba  Ba0  1  0.500  0.000  0.000  1.0
  Ba  Ba1  1  0.815  0.815  0.631  1.0
  Ba  Ba2  1  0.185  0.185  0.369  1.0
  Al  Al3  1  0.065  0.565  0.130  1.0
  Al  Al4  1  0.935  0.435  0.870  1.0
  Si  Si5  1  0.633  0.632  0.266  1.0
  Si  Si6  1  0.367  0.368  0.734  1.0
[/CIF]
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