The crystal structure described by BaAl2(PO5)2 crystallizes in the triclinic P-1 space group. Ba(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(4), two equivalent O(5), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with eight equivalent Al(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, edges with two equivalent Ba(1)O12 cuboctahedra, edges with four equivalent P(1)O4 tetrahedra, and faces with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-59°. Al(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form AlO6 octahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, corners with four equivalent P(1)O4 tetrahedra,  an edgeedge with one Al(1)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Ba(1)O12 cuboctahedra, corners with four equivalent Al(1)O6 octahedra, and edges with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 44-49°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ba(1), one Al(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Al(1), and one P(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to two equivalent Ba(1), one Al(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one Al(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Ba(1) and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaAl2(PO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.980
_cell_length_b   6.121
_cell_length_c   6.699
_cell_angle_alpha   110.706
_cell_angle_beta   106.649
_cell_angle_gamma   93.118
_symmetry_Int_Tables_number   1
_cell_volume   180.207
_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  0.000  0.000  0.000  1.0
  Al  Al1  1  0.313  0.358  0.735  1.0
  Al  Al2  1  0.687  0.642  0.265  1.0
  P  P3  1  0.319  0.801  0.588  1.0
  P  P4  1  0.681  0.199  0.412  1.0
  O  O5  1  0.597  0.746  0.535  1.0
  O  O6  1  0.403  0.254  0.465  1.0
  O  O7  1  0.073  0.767  0.373  1.0
  O  O8  1  0.927  0.233  0.627  1.0
  O  O9  1  0.388  0.062  0.767  1.0
  O  O10  1  0.612  0.938  0.233  1.0
  O  O11  1  0.237  0.651  0.712  1.0
  O  O12  1  0.763  0.349  0.288  1.0
  O  O13  1  0.673  0.525  0.952  1.0
  O  O14  1  0.327  0.475  0.048  1.0
[/CIF]
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The crystal structure described by BaAl2(PO5)2 crystallizes in the triclinic P-1 space group. Ba(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(4), two equivalent O(5), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with eight equivalent Al(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, edges with two equivalent Ba(1)O12 cuboctahedra, edges with four equivalent P(1)O4 tetrahedra, and faces with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-59°. Al(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form AlO6 octahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, corners with four equivalent P(1)O4 tetrahedra,  an edgeedge with one Al(1)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Ba(1)O12 cuboctahedra, corners with four equivalent Al(1)O6 octahedra, and edges with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 44-49°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ba(1), one Al(1), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Al(1), and one P(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to two equivalent Ba(1), one Al(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one Al(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Ba(1) and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaAl2(PO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.980
_cell_length_b   6.121
_cell_length_c   6.699
_cell_angle_alpha   110.706
_cell_angle_beta   106.649
_cell_angle_gamma   93.118
_symmetry_Int_Tables_number   1
_cell_volume   180.207
_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  0.000  0.000  0.000  1.0
  Al  Al1  1  0.313  0.358  0.735  1.0
  Al  Al2  1  0.687  0.642  0.265  1.0
  P  P3  1  0.319  0.801  0.588  1.0
  P  P4  1  0.681  0.199  0.412  1.0
  O  O5  1  0.597  0.746  0.535  1.0
  O  O6  1  0.403  0.254  0.465  1.0
  O  O7  1  0.073  0.767  0.373  1.0
  O  O8  1  0.927  0.233  0.627  1.0
  O  O9  1  0.388  0.062  0.767  1.0
  O  O10  1  0.612  0.938  0.233  1.0
  O  O11  1  0.237  0.651  0.712  1.0
  O  O12  1  0.763  0.349  0.288  1.0
  O  O13  1  0.673  0.525  0.952  1.0
  O  O14  1  0.327  0.475  0.048  1.0
[/CIF]
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