The material structure described by Sr5Ta4O15 crystallizes in the trigonal P-3m1 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to nine equivalent O(1) atoms. In the second Sr site, Sr(2) is bonded to three equivalent O(1), three equivalent O(2), and six equivalent O(3) atoms to form distorted SrO12 cuboctahedra that share corners with nine equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(3)O12 cuboctahedra, faces with three equivalent Ta(2)O6 octahedra, and faces with four equivalent Ta(1)O6 octahedra. In the third Sr site, Sr(3) is bonded to six equivalent O(2) and six equivalent O(3) atoms to form SrO12 cuboctahedra that share corners with six equivalent Sr(3)O12 cuboctahedra, faces with six equivalent Sr(2)O12 cuboctahedra, faces with two equivalent Ta(2)O6 octahedra, and faces with six equivalent Ta(1)O6 octahedra. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form TaO6 octahedra that share corners with three equivalent Ta(1)O6 octahedra, corners with three equivalent Ta(2)O6 octahedra, faces with three equivalent Sr(3)O12 cuboctahedra, and faces with four equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the second Ta site, Ta(2) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form distorted TaO6 octahedra that share corners with three equivalent Ta(1)O6 octahedra,  a faceface with one Sr(3)O12 cuboctahedra, and faces with three equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 10°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Sr(2), three equivalent Sr(1), and one Ta(2) atom. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent Sr(2), two equivalent Sr(3), and two equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Sr(3), two equivalent Sr(2), one Ta(1), and one Ta(2) atom. is represented by the CIF card [CIF]
data_Sr5Ta4O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.669
_cell_length_b   5.669
_cell_length_c   11.543
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   321.310
_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  0.333  0.667  0.440  1.0
  Sr  Sr1  1  0.333  0.667  0.778  1.0
  Sr  Sr2  1  1.000  1.000  0.000  1.0
  Sr  Sr3  1  0.667  0.333  0.222  1.0
  Sr  Sr4  1  0.667  0.333  0.560  1.0
  Ta  Ta5  1  0.333  0.667  0.105  1.0
  Ta  Ta6  1  1.000  1.000  0.318  1.0
  Ta  Ta7  1  0.000  0.000  0.682  1.0
  Ta  Ta8  1  0.667  0.333  0.895  1.0
  O  O9  1  0.169  0.831  0.609  1.0
  O  O10  1  1.000  0.500  0.000  1.0
  O  O11  1  0.165  0.835  0.193  1.0
  O  O12  1  0.165  0.330  0.193  1.0
  O  O13  1  0.169  0.338  0.609  1.0
  O  O14  1  0.338  0.169  0.391  1.0
  O  O15  1  0.670  0.835  0.193  1.0
  O  O16  1  0.500  0.500  0.000  1.0
  O  O17  1  0.330  0.165  0.807  1.0
  O  O18  1  0.662  0.831  0.609  1.0
  O  O19  1  0.500  1.000  0.000  1.0
  O  O20  1  0.835  0.670  0.807  1.0
  O  O21  1  0.831  0.662  0.391  1.0
  O  O22  1  0.835  0.165  0.807  1.0
  O  O23  1  0.831  0.169  0.391  1.0
[/CIF]
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The material structure described by Sr5Ta4O15 crystallizes in the trigonal P-3m1 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to nine equivalent O(1) atoms. In the second Sr site, Sr(2) is bonded to three equivalent O(1), three equivalent O(2), and six equivalent O(3) atoms to form distorted SrO12 cuboctahedra that share corners with nine equivalent Sr(2)O12 cuboctahedra, faces with three equivalent Sr(3)O12 cuboctahedra, faces with three equivalent Ta(2)O6 octahedra, and faces with four equivalent Ta(1)O6 octahedra. In the third Sr site, Sr(3) is bonded to six equivalent O(2) and six equivalent O(3) atoms to form SrO12 cuboctahedra that share corners with six equivalent Sr(3)O12 cuboctahedra, faces with six equivalent Sr(2)O12 cuboctahedra, faces with two equivalent Ta(2)O6 octahedra, and faces with six equivalent Ta(1)O6 octahedra. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form TaO6 octahedra that share corners with three equivalent Ta(1)O6 octahedra, corners with three equivalent Ta(2)O6 octahedra, faces with three equivalent Sr(3)O12 cuboctahedra, and faces with four equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the second Ta site, Ta(2) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form distorted TaO6 octahedra that share corners with three equivalent Ta(1)O6 octahedra,  a faceface with one Sr(3)O12 cuboctahedra, and faces with three equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 10°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Sr(2), three equivalent Sr(1), and one Ta(2) atom. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent Sr(2), two equivalent Sr(3), and two equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Sr(3), two equivalent Sr(2), one Ta(1), and one Ta(2) atom. is represented by the CIF card [CIF]
data_Sr5Ta4O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.669
_cell_length_b   5.669
_cell_length_c   11.543
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   321.310
_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  0.333  0.667  0.440  1.0
  Sr  Sr1  1  0.333  0.667  0.778  1.0
  Sr  Sr2  1  1.000  1.000  0.000  1.0
  Sr  Sr3  1  0.667  0.333  0.222  1.0
  Sr  Sr4  1  0.667  0.333  0.560  1.0
  Ta  Ta5  1  0.333  0.667  0.105  1.0
  Ta  Ta6  1  1.000  1.000  0.318  1.0
  Ta  Ta7  1  0.000  0.000  0.682  1.0
  Ta  Ta8  1  0.667  0.333  0.895  1.0
  O  O9  1  0.169  0.831  0.609  1.0
  O  O10  1  1.000  0.500  0.000  1.0
  O  O11  1  0.165  0.835  0.193  1.0
  O  O12  1  0.165  0.330  0.193  1.0
  O  O13  1  0.169  0.338  0.609  1.0
  O  O14  1  0.338  0.169  0.391  1.0
  O  O15  1  0.670  0.835  0.193  1.0
  O  O16  1  0.500  0.500  0.000  1.0
  O  O17  1  0.330  0.165  0.807  1.0
  O  O18  1  0.662  0.831  0.609  1.0
  O  O19  1  0.500  1.000  0.000  1.0
  O  O20  1  0.835  0.670  0.807  1.0
  O  O21  1  0.831  0.662  0.391  1.0
  O  O22  1  0.835  0.165  0.807  1.0
  O  O23  1  0.831  0.169  0.391  1.0
[/CIF]
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