The structure described by Sr4Ta3PO14 crystallizes in the monoclinic Cm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(6), one O(7), two equivalent O(10), two equivalent O(11), two equivalent O(4), two equivalent O(8), and two equivalent O(9) atoms to form distorted SrO12 cuboctahedra that share corners with two equivalent Sr(1)O12 cuboctahedra, corners with four equivalent Sr(2)O12 cuboctahedra, edges with two equivalent P(1)O5 trigonal bipyramids, faces with two equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Sr(2)O12 cuboctahedra, faces with two equivalent Ta(2)O6 octahedra, and faces with four equivalent Ta(1)O6 octahedra. In the second Sr site, Sr(2) is bonded to one O(5), one O(8), two equivalent O(10), two equivalent O(12), two equivalent O(3), two equivalent O(7), and two equivalent O(9) atoms to form distorted SrO12 cuboctahedra that share corners with two equivalent Sr(2)O12 cuboctahedra, corners with four equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Sr(2)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with four equivalent Ta(2)O6 octahedra. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one O(1), one O(14), one O(6), two equivalent O(13), two equivalent O(2), and two equivalent O(4) atoms. In the fourth Sr site, Sr(4) is bonded in a 6-coordinate geometry to one O(13), one O(2), two equivalent O(1), and two equivalent O(14) atoms. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(10), one O(11), one O(4), one O(9), and two equivalent O(8) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra,  a cornercorner with one P(1)O5 trigonal bipyramid, faces with two equivalent Sr(2)O12 cuboctahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 6-15°. In the second Ta site, Ta(2) is bonded to one O(10), one O(12), one O(3), one O(9), and two equivalent O(7) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with four equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 6-15°. In the third Ta site, Ta(3) is bonded to one O(1), one O(12), one O(14), one O(3), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 9-19°. P(1) is bonded to one O(11), one O(13), one O(2), and two equivalent O(6) atoms to form distorted PO5 trigonal bipyramids that share  a cornercorner with one Ta(1)O6 octahedra, corners with two equivalent P(1)O5 trigonal bipyramids, and edges with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 44°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(3), two equivalent Sr(4), and one Ta(3) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Sr(4), two equivalent Sr(3), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(2), one Ta(2), and one Ta(3) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(3), and one Ta(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Sr(2) and two equivalent Ta(3) atoms. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Sr(3), and two equivalent P(1) atoms. In the seventh O site, O(7) is bonded in a distorted linear geometry to one Sr(1), two equivalent Sr(2), and two equivalent Ta(2) atoms. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Sr(2), two equivalent Sr(1), and two equivalent Ta(1) atoms. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(2) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(2) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Ta(1), and one P(1) atom. In the twelfth O site, O(12) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(2), one Ta(2), and one Ta(3) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one Sr(4), two equivalent Sr(3), and one P(1) atom. In the fourteenth O site, O(14) is bonded to one Sr(3), two equivalent Sr(4), and one Ta(3) atom to form distorted corner-sharing OSr3Ta tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr4Ta3PO14
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.953
_cell_length_b   5.811
_cell_length_c   13.499
_cell_angle_alpha   94.779
_cell_angle_beta   98.420
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   305.654
_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  0.566  0.809  0.131  1.0
  Sr  Sr1  1  0.445  0.264  0.890  1.0
  Sr  Sr2  1  0.694  0.166  0.387  1.0
  Sr  Sr3  1  0.284  0.720  0.568  1.0
  Ta  Ta4  1  0.056  0.309  0.112  1.0
  Ta  Ta5  1  0.946  0.769  0.891  1.0
  Ta  Ta6  1  0.836  0.233  0.671  1.0
  P  P7  1  0.166  0.670  0.332  1.0
  O  O8  1  0.792  0.469  0.585  1.0
  O  O9  1  0.199  0.904  0.398  1.0
  O  O10  1  0.902  0.493  0.805  1.0
  O  O11  1  0.107  0.113  0.214  1.0
  O  O12  1  0.348  0.234  0.696  1.0
  O  O13  1  0.658  0.708  0.316  1.0
  O  O14  1  0.454  0.788  0.908  1.0
  O  O15  1  0.551  0.335  0.102  1.0
  O  O16  1  0.006  0.580  0.013  1.0
  O  O17  1  0.001  0.067  0.003  1.0
  O  O18  1  0.107  0.614  0.213  1.0
  O  O19  1  0.899  0.008  0.798  1.0
  O  O20  1  0.198  0.459  0.395  1.0
  O  O21  1  0.786  0.988  0.571  1.0
[/CIF]
.
The structure described by Sr4Ta3PO14 crystallizes in the monoclinic Cm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(6), one O(7), two equivalent O(10), two equivalent O(11), two equivalent O(4), two equivalent O(8), and two equivalent O(9) atoms to form distorted SrO12 cuboctahedra that share corners with two equivalent Sr(1)O12 cuboctahedra, corners with four equivalent Sr(2)O12 cuboctahedra, edges with two equivalent P(1)O5 trigonal bipyramids, faces with two equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Sr(2)O12 cuboctahedra, faces with two equivalent Ta(2)O6 octahedra, and faces with four equivalent Ta(1)O6 octahedra. In the second Sr site, Sr(2) is bonded to one O(5), one O(8), two equivalent O(10), two equivalent O(12), two equivalent O(3), two equivalent O(7), and two equivalent O(9) atoms to form distorted SrO12 cuboctahedra that share corners with two equivalent Sr(2)O12 cuboctahedra, corners with four equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Sr(2)O12 cuboctahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(3)O6 octahedra, and faces with four equivalent Ta(2)O6 octahedra. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one O(1), one O(14), one O(6), two equivalent O(13), two equivalent O(2), and two equivalent O(4) atoms. In the fourth Sr site, Sr(4) is bonded in a 6-coordinate geometry to one O(13), one O(2), two equivalent O(1), and two equivalent O(14) atoms. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(10), one O(11), one O(4), one O(9), and two equivalent O(8) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra,  a cornercorner with one P(1)O5 trigonal bipyramid, faces with two equivalent Sr(2)O12 cuboctahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 6-15°. In the second Ta site, Ta(2) is bonded to one O(10), one O(12), one O(3), one O(9), and two equivalent O(7) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with four equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 6-15°. In the third Ta site, Ta(3) is bonded to one O(1), one O(12), one O(14), one O(3), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 9-19°. P(1) is bonded to one O(11), one O(13), one O(2), and two equivalent O(6) atoms to form distorted PO5 trigonal bipyramids that share  a cornercorner with one Ta(1)O6 octahedra, corners with two equivalent P(1)O5 trigonal bipyramids, and edges with two equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 44°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(3), two equivalent Sr(4), and one Ta(3) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Sr(4), two equivalent Sr(3), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(2), one Ta(2), and one Ta(3) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(3), and one Ta(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Sr(2) and two equivalent Ta(3) atoms. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Sr(3), and two equivalent P(1) atoms. In the seventh O site, O(7) is bonded in a distorted linear geometry to one Sr(1), two equivalent Sr(2), and two equivalent Ta(2) atoms. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Sr(2), two equivalent Sr(1), and two equivalent Ta(1) atoms. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(2) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(2) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Ta(1), and one P(1) atom. In the twelfth O site, O(12) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(2), one Ta(2), and one Ta(3) atom. In the thirteenth O site, O(13) is bonded in a distorted single-bond geometry to one Sr(4), two equivalent Sr(3), and one P(1) atom. In the fourteenth O site, O(14) is bonded to one Sr(3), two equivalent Sr(4), and one Ta(3) atom to form distorted corner-sharing OSr3Ta tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr4Ta3PO14
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.953
_cell_length_b   5.811
_cell_length_c   13.499
_cell_angle_alpha   94.779
_cell_angle_beta   98.420
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   305.654
_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  0.566  0.809  0.131  1.0
  Sr  Sr1  1  0.445  0.264  0.890  1.0
  Sr  Sr2  1  0.694  0.166  0.387  1.0
  Sr  Sr3  1  0.284  0.720  0.568  1.0
  Ta  Ta4  1  0.056  0.309  0.112  1.0
  Ta  Ta5  1  0.946  0.769  0.891  1.0
  Ta  Ta6  1  0.836  0.233  0.671  1.0
  P  P7  1  0.166  0.670  0.332  1.0
  O  O8  1  0.792  0.469  0.585  1.0
  O  O9  1  0.199  0.904  0.398  1.0
  O  O10  1  0.902  0.493  0.805  1.0
  O  O11  1  0.107  0.113  0.214  1.0
  O  O12  1  0.348  0.234  0.696  1.0
  O  O13  1  0.658  0.708  0.316  1.0
  O  O14  1  0.454  0.788  0.908  1.0
  O  O15  1  0.551  0.335  0.102  1.0
  O  O16  1  0.006  0.580  0.013  1.0
  O  O17  1  0.001  0.067  0.003  1.0
  O  O18  1  0.107  0.614  0.213  1.0
  O  O19  1  0.899  0.008  0.798  1.0
  O  O20  1  0.198  0.459  0.395  1.0
  O  O21  1  0.786  0.988  0.571  1.0
[/CIF]
.