The crystal structure described by SrAl3(PO7)2 crystallizes in the trigonal R-3m space group. Sr(1) is bonded to six equivalent O(2) and six equivalent O(3) atoms to form SrO12 cuboctahedra that share corners with six equivalent P(1)O4 tetrahedra and faces with six equivalent Al(1)O6 octahedra. Al(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form AlO6 octahedra that share corners with four equivalent Al(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 38°. P(1) is bonded to one O(1) and three equivalent O(2) atoms to form PO4 tetrahedra that share corners with three equivalent Sr(1)O12 cuboctahedra and corners with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one P(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Sr(1), one Al(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Sr(1) and two equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_SrAl3(PO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.993
_cell_length_b   6.993
_cell_length_c   6.993
_cell_angle_alpha   60.104
_cell_angle_beta   60.104
_cell_angle_gamma   60.104
_symmetry_Int_Tables_number   1
_cell_volume   242.358
_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
  Sr  Sr0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.500  0.000  1.0
  Al  Al2  1  0.000  0.000  0.500  1.0
  Al  Al3  1  0.500  0.000  0.000  1.0
  P  P4  1  0.690  0.690  0.690  1.0
  P  P5  1  0.310  0.310  0.310  1.0
  O  O6  1  0.600  0.600  0.600  1.0
  O  O7  1  0.400  0.400  0.400  1.0
  O  O8  1  0.842  0.482  0.842  1.0
  O  O9  1  0.842  0.842  0.482  1.0
  O  O10  1  0.482  0.842  0.842  1.0
  O  O11  1  0.158  0.518  0.158  1.0
  O  O12  1  0.158  0.158  0.518  1.0
  O  O13  1  0.518  0.158  0.158  1.0
  O  O14  1  0.748  0.089  0.748  1.0
  O  O15  1  0.748  0.748  0.089  1.0
  O  O16  1  0.089  0.748  0.748  1.0
  O  O17  1  0.252  0.911  0.252  1.0
  O  O18  1  0.252  0.252  0.911  1.0
  O  O19  1  0.911  0.252  0.252  1.0
[/CIF]
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The crystal structure described by SrAl3(PO7)2 crystallizes in the trigonal R-3m space group. Sr(1) is bonded to six equivalent O(2) and six equivalent O(3) atoms to form SrO12 cuboctahedra that share corners with six equivalent P(1)O4 tetrahedra and faces with six equivalent Al(1)O6 octahedra. Al(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form AlO6 octahedra that share corners with four equivalent Al(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 38°. P(1) is bonded to one O(1) and three equivalent O(2) atoms to form PO4 tetrahedra that share corners with three equivalent Sr(1)O12 cuboctahedra and corners with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one P(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Sr(1), one Al(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Sr(1) and two equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_SrAl3(PO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.993
_cell_length_b   6.993
_cell_length_c   6.993
_cell_angle_alpha   60.104
_cell_angle_beta   60.104
_cell_angle_gamma   60.104
_symmetry_Int_Tables_number   1
_cell_volume   242.358
_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
  Sr  Sr0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.500  0.000  1.0
  Al  Al2  1  0.000  0.000  0.500  1.0
  Al  Al3  1  0.500  0.000  0.000  1.0
  P  P4  1  0.690  0.690  0.690  1.0
  P  P5  1  0.310  0.310  0.310  1.0
  O  O6  1  0.600  0.600  0.600  1.0
  O  O7  1  0.400  0.400  0.400  1.0
  O  O8  1  0.842  0.482  0.842  1.0
  O  O9  1  0.842  0.842  0.482  1.0
  O  O10  1  0.482  0.842  0.842  1.0
  O  O11  1  0.158  0.518  0.158  1.0
  O  O12  1  0.158  0.158  0.518  1.0
  O  O13  1  0.518  0.158  0.158  1.0
  O  O14  1  0.748  0.089  0.748  1.0
  O  O15  1  0.748  0.748  0.089  1.0
  O  O16  1  0.089  0.748  0.748  1.0
  O  O17  1  0.252  0.911  0.252  1.0
  O  O18  1  0.252  0.252  0.911  1.0
  O  O19  1  0.911  0.252  0.252  1.0
[/CIF]
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