The material structure described by Sr3TiTa4O15 crystallizes in the monoclinic Pc space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(12), one O(13), one O(3), one O(4), two equivalent O(10), two equivalent O(11), two equivalent O(7), and two equivalent O(8) atoms to form SrO12 cuboctahedra that share faces with two equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Ti(1)O6 octahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Ta(4)O6 octahedra. In the second Sr site, Sr(2) is bonded in a 11-coordinate geometry to one O(13), one O(4), one O(9), two equivalent O(14), two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms. In the third Sr site, Sr(3) is bonded in a 11-coordinate geometry to one O(12), one O(3), one O(9), two equivalent O(1), two equivalent O(15), two equivalent O(6), and two equivalent O(7) atoms. Ti(1) is bonded to one O(1), one O(10), one O(5), one O(7), and two equivalent O(12) atoms to form TiO6 octahedra that share  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ta(4)O6 octahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 8-45°. There are four inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(11), one O(2), one O(6), one O(8), and two equivalent O(13) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-42°. In the second Ta site, Ta(2) is bonded to one O(1), one O(14), one O(15), one O(2), and two equivalent O(9) atoms to form TaO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, and corners with two equivalent Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-39°. In the third Ta site, Ta(3) is bonded to one O(11), one O(15), one O(6), one O(7), and two equivalent O(3) atoms to form TaO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 8-42°. In the fourth Ta site, Ta(4) is bonded to one O(10), one O(14), one O(5), one O(8), and two equivalent O(4) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ta(4)O6 octahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-45°. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Sr(3), one Ti(1), and one Ta(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Sr(2), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Sr(3), and two equivalent Ta(3) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Sr(1), one Sr(2), and two equivalent Ta(4) atoms. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Sr(2), one Ti(1), and one Ta(4) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(3), one Ta(1), and one Ta(3) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), one Ti(1), and one Ta(3) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(4) atom. In the ninth O site, O(9) is bonded in a linear geometry to one Sr(2), one Sr(3), and two equivalent Ta(2) atoms. In the tenth O site, O(10) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(1), one Ti(1), and one Ta(4) atom. In the eleventh O site, O(11) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(1), one Ta(1), and one Ta(3) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), and two equivalent Ti(1) atoms. In the thirteenth O site, O(13) is bonded in a distorted linear geometry to one Sr(1), one Sr(2), and two equivalent Ta(1) atoms. In the fourteenth O site, O(14) is bonded in a distorted bent 150 degrees geometry to two equivalent Sr(2), one Ta(2), and one Ta(4) atom. In the fifteenth O site, O(15) is bonded in a bent 150 degrees geometry to two equivalent Sr(3), one Ta(2), and one Ta(3) atom. is represented by the CIF card [CIF]
data_Sr3Ta4TiO15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.971
_cell_length_b   12.582
_cell_length_c   12.549
_cell_angle_alpha   90.000
_cell_angle_beta   89.995
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   626.975
_cell_formula_units_Z   2
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  0.372  0.503  0.494  1.0
  Sr  Sr1  1  0.372  0.997  0.994  1.0
  Sr  Sr2  1  0.370  0.651  0.807  1.0
  Sr  Sr3  1  0.369  0.380  0.210  1.0
  Sr  Sr4  1  0.370  0.849  0.307  1.0
  Sr  Sr5  1  0.369  0.120  0.710  1.0
  Ta  Ta6  1  0.874  0.420  0.709  1.0
  Ta  Ta7  1  0.874  0.080  0.209  1.0
  Ta  Ta8  1  0.866  0.498  0.003  1.0
  Ta  Ta9  1  0.866  0.002  0.503  1.0
  Ta  Ta10  1  0.878  0.289  0.423  1.0
  Ta  Ta11  1  0.881  0.713  0.575  1.0
  Ta  Ta12  1  0.878  0.211  0.923  1.0
  Ta  Ta13  1  0.881  0.787  0.075  1.0
  Ti  Ti14  1  0.844  0.587  0.290  1.0
  Ti  Ti15  1  0.844  0.913  0.790  1.0
  O  O16  1  0.885  0.503  0.158  1.0
  O  O17  1  0.889  0.503  0.842  1.0
  O  O18  1  0.885  0.997  0.658  1.0
  O  O19  1  0.889  0.997  0.342  1.0
  O  O20  1  0.384  0.297  0.412  1.0
  O  O21  1  0.383  0.703  0.586  1.0
  O  O22  1  0.384  0.203  0.912  1.0
  O  O23  1  0.383  0.797  0.086  1.0
  O  O24  1  0.879  0.772  0.728  1.0
  O  O25  1  0.883  0.223  0.273  1.0
  O  O26  1  0.879  0.728  0.228  1.0
  O  O27  1  0.883  0.277  0.773  1.0
  O  O28  1  0.888  0.431  0.351  1.0
  O  O29  1  0.887  0.568  0.645  1.0
  O  O30  1  0.888  0.069  0.851  1.0
  O  O31  1  0.887  0.932  0.145  1.0
  O  O32  1  0.382  0.500  0.001  1.0
  O  O33  1  0.382  1.000  0.501  1.0
  O  O34  1  0.883  0.630  0.441  1.0
  O  O35  1  0.883  0.372  0.557  1.0
  O  O36  1  0.883  0.870  0.941  1.0
  O  O37  1  0.883  0.128  0.057  1.0
  O  O38  1  0.391  0.576  0.297  1.0
  O  O39  1  0.383  0.425  0.701  1.0
  O  O40  1  0.391  0.924  0.797  1.0
  O  O41  1  0.383  0.075  0.201  1.0
  O  O42  1  0.887  0.841  0.489  1.0
  O  O43  1  0.889  0.158  0.507  1.0
  O  O44  1  0.887  0.659  0.989  1.0
  O  O45  1  0.889  0.342  0.007  1.0
[/CIF]
.
The material structure described by Sr3TiTa4O15 crystallizes in the monoclinic Pc space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(12), one O(13), one O(3), one O(4), two equivalent O(10), two equivalent O(11), two equivalent O(7), and two equivalent O(8) atoms to form SrO12 cuboctahedra that share faces with two equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Ti(1)O6 octahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Ta(4)O6 octahedra. In the second Sr site, Sr(2) is bonded in a 11-coordinate geometry to one O(13), one O(4), one O(9), two equivalent O(14), two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms. In the third Sr site, Sr(3) is bonded in a 11-coordinate geometry to one O(12), one O(3), one O(9), two equivalent O(1), two equivalent O(15), two equivalent O(6), and two equivalent O(7) atoms. Ti(1) is bonded to one O(1), one O(10), one O(5), one O(7), and two equivalent O(12) atoms to form TiO6 octahedra that share  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ta(4)O6 octahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 8-45°. There are four inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(11), one O(2), one O(6), one O(8), and two equivalent O(13) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-42°. In the second Ta site, Ta(2) is bonded to one O(1), one O(14), one O(15), one O(2), and two equivalent O(9) atoms to form TaO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, and corners with two equivalent Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-39°. In the third Ta site, Ta(3) is bonded to one O(11), one O(15), one O(6), one O(7), and two equivalent O(3) atoms to form TaO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 8-42°. In the fourth Ta site, Ta(4) is bonded to one O(10), one O(14), one O(5), one O(8), and two equivalent O(4) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra, corners with two equivalent Ti(1)O6 octahedra, corners with two equivalent Ta(4)O6 octahedra, and faces with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-45°. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Sr(3), one Ti(1), and one Ta(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Sr(2), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Sr(3), and two equivalent Ta(3) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Sr(1), one Sr(2), and two equivalent Ta(4) atoms. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Sr(2), one Ti(1), and one Ta(4) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(3), one Ta(1), and one Ta(3) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), one Ti(1), and one Ta(3) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(4) atom. In the ninth O site, O(9) is bonded in a linear geometry to one Sr(2), one Sr(3), and two equivalent Ta(2) atoms. In the tenth O site, O(10) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(1), one Ti(1), and one Ta(4) atom. In the eleventh O site, O(11) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(1), one Ta(1), and one Ta(3) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(3), and two equivalent Ti(1) atoms. In the thirteenth O site, O(13) is bonded in a distorted linear geometry to one Sr(1), one Sr(2), and two equivalent Ta(1) atoms. In the fourteenth O site, O(14) is bonded in a distorted bent 150 degrees geometry to two equivalent Sr(2), one Ta(2), and one Ta(4) atom. In the fifteenth O site, O(15) is bonded in a bent 150 degrees geometry to two equivalent Sr(3), one Ta(2), and one Ta(3) atom. is represented by the CIF card [CIF]
data_Sr3Ta4TiO15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.971
_cell_length_b   12.582
_cell_length_c   12.549
_cell_angle_alpha   90.000
_cell_angle_beta   89.995
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   626.975
_cell_formula_units_Z   2
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  0.372  0.503  0.494  1.0
  Sr  Sr1  1  0.372  0.997  0.994  1.0
  Sr  Sr2  1  0.370  0.651  0.807  1.0
  Sr  Sr3  1  0.369  0.380  0.210  1.0
  Sr  Sr4  1  0.370  0.849  0.307  1.0
  Sr  Sr5  1  0.369  0.120  0.710  1.0
  Ta  Ta6  1  0.874  0.420  0.709  1.0
  Ta  Ta7  1  0.874  0.080  0.209  1.0
  Ta  Ta8  1  0.866  0.498  0.003  1.0
  Ta  Ta9  1  0.866  0.002  0.503  1.0
  Ta  Ta10  1  0.878  0.289  0.423  1.0
  Ta  Ta11  1  0.881  0.713  0.575  1.0
  Ta  Ta12  1  0.878  0.211  0.923  1.0
  Ta  Ta13  1  0.881  0.787  0.075  1.0
  Ti  Ti14  1  0.844  0.587  0.290  1.0
  Ti  Ti15  1  0.844  0.913  0.790  1.0
  O  O16  1  0.885  0.503  0.158  1.0
  O  O17  1  0.889  0.503  0.842  1.0
  O  O18  1  0.885  0.997  0.658  1.0
  O  O19  1  0.889  0.997  0.342  1.0
  O  O20  1  0.384  0.297  0.412  1.0
  O  O21  1  0.383  0.703  0.586  1.0
  O  O22  1  0.384  0.203  0.912  1.0
  O  O23  1  0.383  0.797  0.086  1.0
  O  O24  1  0.879  0.772  0.728  1.0
  O  O25  1  0.883  0.223  0.273  1.0
  O  O26  1  0.879  0.728  0.228  1.0
  O  O27  1  0.883  0.277  0.773  1.0
  O  O28  1  0.888  0.431  0.351  1.0
  O  O29  1  0.887  0.568  0.645  1.0
  O  O30  1  0.888  0.069  0.851  1.0
  O  O31  1  0.887  0.932  0.145  1.0
  O  O32  1  0.382  0.500  0.001  1.0
  O  O33  1  0.382  1.000  0.501  1.0
  O  O34  1  0.883  0.630  0.441  1.0
  O  O35  1  0.883  0.372  0.557  1.0
  O  O36  1  0.883  0.870  0.941  1.0
  O  O37  1  0.883  0.128  0.057  1.0
  O  O38  1  0.391  0.576  0.297  1.0
  O  O39  1  0.383  0.425  0.701  1.0
  O  O40  1  0.391  0.924  0.797  1.0
  O  O41  1  0.383  0.075  0.201  1.0
  O  O42  1  0.887  0.841  0.489  1.0
  O  O43  1  0.889  0.158  0.507  1.0
  O  O44  1  0.887  0.659  0.989  1.0
  O  O45  1  0.889  0.342  0.007  1.0
[/CIF]
.