The compound described by Ba3AlO4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(3), and three equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form distorted BaO6 pentagonal pyramids that share corners with four equivalent Al(1)O4 tetrahedra, edges with two equivalent Ba(2)O6 pentagonal pyramids, and  an edgeedge with one Al(1)O4 tetrahedra. Al(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form AlO4 tetrahedra that share corners with four equivalent Ba(2)O6 pentagonal pyramids and  an edgeedge with one Ba(2)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(2), three equivalent Ba(1), and one Al(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(2), four equivalent Ba(1), and one Al(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Ba(2), four equivalent Ba(1), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3AlO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.565
_cell_length_b   8.252
_cell_length_c   7.307
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   637.039
_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
  Ba  Ba0  1  0.336  0.526  0.897  1.0
  Ba  Ba1  1  0.836  0.974  0.603  1.0
  Ba  Ba2  1  0.664  0.026  0.103  1.0
  Ba  Ba3  1  0.164  0.474  0.397  1.0
  Ba  Ba4  1  0.664  0.474  0.103  1.0
  Ba  Ba5  1  0.164  0.026  0.397  1.0
  Ba  Ba6  1  0.336  0.974  0.897  1.0
  Ba  Ba7  1  0.836  0.526  0.603  1.0
  Ba  Ba8  1  0.464  0.750  0.404  1.0
  Ba  Ba9  1  0.964  0.750  0.096  1.0
  Ba  Ba10  1  0.536  0.250  0.596  1.0
  Ba  Ba11  1  0.036  0.250  0.904  1.0
  Al  Al12  1  0.104  0.750  0.688  1.0
  Al  Al13  1  0.604  0.750  0.812  1.0
  Al  Al14  1  0.896  0.250  0.312  1.0
  Al  Al15  1  0.396  0.250  0.188  1.0
  O  O16  1  0.072  0.567  0.803  1.0
  O  O17  1  0.572  0.933  0.697  1.0
  O  O18  1  0.928  0.067  0.197  1.0
  O  O19  1  0.428  0.433  0.303  1.0
  O  O20  1  0.928  0.433  0.197  1.0
  O  O21  1  0.428  0.067  0.303  1.0
  O  O22  1  0.072  0.933  0.803  1.0
  O  O23  1  0.572  0.567  0.697  1.0
  O  O24  1  0.013  0.750  0.483  1.0
  O  O25  1  0.513  0.750  0.017  1.0
  O  O26  1  0.987  0.250  0.517  1.0
  O  O27  1  0.487  0.250  0.983  1.0
  O  O28  1  0.267  0.750  0.628  1.0
  O  O29  1  0.767  0.750  0.872  1.0
  O  O30  1  0.733  0.250  0.372  1.0
  O  O31  1  0.233  0.250  0.128  1.0
[/CIF]
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The compound described by Ba3AlO4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(3), and three equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form distorted BaO6 pentagonal pyramids that share corners with four equivalent Al(1)O4 tetrahedra, edges with two equivalent Ba(2)O6 pentagonal pyramids, and  an edgeedge with one Al(1)O4 tetrahedra. Al(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form AlO4 tetrahedra that share corners with four equivalent Ba(2)O6 pentagonal pyramids and  an edgeedge with one Ba(2)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(2), three equivalent Ba(1), and one Al(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(2), four equivalent Ba(1), and one Al(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Ba(2), four equivalent Ba(1), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3AlO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.565
_cell_length_b   8.252
_cell_length_c   7.307
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   637.039
_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
  Ba  Ba0  1  0.336  0.526  0.897  1.0
  Ba  Ba1  1  0.836  0.974  0.603  1.0
  Ba  Ba2  1  0.664  0.026  0.103  1.0
  Ba  Ba3  1  0.164  0.474  0.397  1.0
  Ba  Ba4  1  0.664  0.474  0.103  1.0
  Ba  Ba5  1  0.164  0.026  0.397  1.0
  Ba  Ba6  1  0.336  0.974  0.897  1.0
  Ba  Ba7  1  0.836  0.526  0.603  1.0
  Ba  Ba8  1  0.464  0.750  0.404  1.0
  Ba  Ba9  1  0.964  0.750  0.096  1.0
  Ba  Ba10  1  0.536  0.250  0.596  1.0
  Ba  Ba11  1  0.036  0.250  0.904  1.0
  Al  Al12  1  0.104  0.750  0.688  1.0
  Al  Al13  1  0.604  0.750  0.812  1.0
  Al  Al14  1  0.896  0.250  0.312  1.0
  Al  Al15  1  0.396  0.250  0.188  1.0
  O  O16  1  0.072  0.567  0.803  1.0
  O  O17  1  0.572  0.933  0.697  1.0
  O  O18  1  0.928  0.067  0.197  1.0
  O  O19  1  0.428  0.433  0.303  1.0
  O  O20  1  0.928  0.433  0.197  1.0
  O  O21  1  0.428  0.067  0.303  1.0
  O  O22  1  0.072  0.933  0.803  1.0
  O  O23  1  0.572  0.567  0.697  1.0
  O  O24  1  0.013  0.750  0.483  1.0
  O  O25  1  0.513  0.750  0.017  1.0
  O  O26  1  0.987  0.250  0.517  1.0
  O  O27  1  0.487  0.250  0.983  1.0
  O  O28  1  0.267  0.750  0.628  1.0
  O  O29  1  0.767  0.750  0.872  1.0
  O  O30  1  0.733  0.250  0.372  1.0
  O  O31  1  0.233  0.250  0.128  1.0
[/CIF]
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