The crystal structure described by BaAl3(PO7)2 crystallizes in the monoclinic Cm space group. Ba(1) is bonded to one O(1), one O(6), one O(7), one O(8), two equivalent O(10), two equivalent O(3), two equivalent O(5), and two equivalent O(9) atoms to form BaO12 cuboctahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, faces with two equivalent Al(2)O6 octahedra, and faces with four equivalent Al(1)O6 octahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(10), one O(3), one O(5), one O(6), and one O(9) atom to form AlO6 octahedra that share corners with two equivalent Al(1)O6 octahedra, corners with two equivalent Al(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 36-39°. In the second Al site, Al(2) is bonded to one O(7), one O(8), two equivalent O(5), and two equivalent O(9) atoms to form AlO6 octahedra that share corners with four equivalent Al(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 36-39°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(4), one O(8), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with three equivalent Ba(1)O12 cuboctahedra,  a cornercorner with one Al(2)O6 octahedra, and corners with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. In the second P site, P(2) is bonded to one O(2), one O(7), and two equivalent O(10) atoms to form PO4 tetrahedra that share corners with three equivalent Ba(1)O12 cuboctahedra,  a cornercorner with one Al(2)O6 octahedra, and corners with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Ba(1) and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a single-bond geometry to one P(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), one Al(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ba(1), one Al(1), and one Al(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ba(1) and two equivalent Al(1) atoms. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ba(1), one Al(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Al(2), and one P(1) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Al(1), and one Al(2) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Ba(1), one Al(1), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaAl3(PO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.045
_cell_length_b   7.045
_cell_length_c   7.479
_cell_angle_alpha   61.058
_cell_angle_beta   61.058
_cell_angle_gamma   59.951
_symmetry_Int_Tables_number   1
_cell_volume   266.510
_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  0.151  0.151  0.180  1.0
  Al  Al1  1  0.150  0.653  0.682  1.0
  Al  Al2  1  0.653  0.150  0.682  1.0
  Al  Al3  1  0.157  0.157  0.672  1.0
  P  P4  1  0.453  0.453  0.287  1.0
  P  P5  1  0.849  0.849  0.075  1.0
  O  O6  1  0.902  0.902  0.601  1.0
  O  O7  1  0.763  0.763  0.324  1.0
  O  O8  1  0.298  0.660  0.377  1.0
  O  O9  1  0.660  0.298  0.377  1.0
  O  O10  1  0.547  0.547  0.041  1.0
  O  O11  1  0.898  0.238  0.607  1.0
  O  O12  1  0.238  0.898  0.607  1.0
  O  O13  1  0.406  0.406  0.754  1.0
  O  O14  1  0.997  0.997  0.995  1.0
  O  O15  1  0.305  0.305  0.368  1.0
  O  O16  1  0.066  0.405  0.758  1.0
  O  O17  1  0.405  0.066  0.758  1.0
  O  O18  1  0.001  0.642  0.985  1.0
  O  O19  1  0.642  0.001  0.985  1.0
[/CIF]
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The crystal structure described by BaAl3(PO7)2 crystallizes in the monoclinic Cm space group. Ba(1) is bonded to one O(1), one O(6), one O(7), one O(8), two equivalent O(10), two equivalent O(3), two equivalent O(5), and two equivalent O(9) atoms to form BaO12 cuboctahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, faces with two equivalent Al(2)O6 octahedra, and faces with four equivalent Al(1)O6 octahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(10), one O(3), one O(5), one O(6), and one O(9) atom to form AlO6 octahedra that share corners with two equivalent Al(1)O6 octahedra, corners with two equivalent Al(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 36-39°. In the second Al site, Al(2) is bonded to one O(7), one O(8), two equivalent O(5), and two equivalent O(9) atoms to form AlO6 octahedra that share corners with four equivalent Al(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 36-39°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(4), one O(8), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with three equivalent Ba(1)O12 cuboctahedra,  a cornercorner with one Al(2)O6 octahedra, and corners with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. In the second P site, P(2) is bonded to one O(2), one O(7), and two equivalent O(10) atoms to form PO4 tetrahedra that share corners with three equivalent Ba(1)O12 cuboctahedra,  a cornercorner with one Al(2)O6 octahedra, and corners with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Ba(1) and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a single-bond geometry to one P(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), one Al(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ba(1), one Al(1), and one Al(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ba(1) and two equivalent Al(1) atoms. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ba(1), one Al(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Al(2), and one P(1) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Al(1), and one Al(2) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Ba(1), one Al(1), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaAl3(PO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.045
_cell_length_b   7.045
_cell_length_c   7.479
_cell_angle_alpha   61.058
_cell_angle_beta   61.058
_cell_angle_gamma   59.951
_symmetry_Int_Tables_number   1
_cell_volume   266.510
_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  0.151  0.151  0.180  1.0
  Al  Al1  1  0.150  0.653  0.682  1.0
  Al  Al2  1  0.653  0.150  0.682  1.0
  Al  Al3  1  0.157  0.157  0.672  1.0
  P  P4  1  0.453  0.453  0.287  1.0
  P  P5  1  0.849  0.849  0.075  1.0
  O  O6  1  0.902  0.902  0.601  1.0
  O  O7  1  0.763  0.763  0.324  1.0
  O  O8  1  0.298  0.660  0.377  1.0
  O  O9  1  0.660  0.298  0.377  1.0
  O  O10  1  0.547  0.547  0.041  1.0
  O  O11  1  0.898  0.238  0.607  1.0
  O  O12  1  0.238  0.898  0.607  1.0
  O  O13  1  0.406  0.406  0.754  1.0
  O  O14  1  0.997  0.997  0.995  1.0
  O  O15  1  0.305  0.305  0.368  1.0
  O  O16  1  0.066  0.405  0.758  1.0
  O  O17  1  0.405  0.066  0.758  1.0
  O  O18  1  0.001  0.642  0.985  1.0
  O  O19  1  0.642  0.001  0.985  1.0
[/CIF]
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