The material structure described by Ba2Ta15O32 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one O(13), one O(14), one O(15), one O(16), one O(17), one O(18), one O(19), one O(20), one O(21), one O(7), one O(8), and one O(9) atom to form distorted BaO12 cuboctahedra that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra, corners with three equivalent Ta(7)O6 octahedra, edges with three equivalent Ba(2)O12 cuboctahedra,  an edgeedge with one Ta(4)O6 octahedra,  an edgeedge with one Ta(5)O6 octahedra,  an edgeedge with one Ta(6)O6 octahedra,  an edgeedge with one Ta(10)O5 square pyramid,  an edgeedge with one Ta(8)O5 square pyramid,  an edgeedge with one Ta(9)O5 square pyramid,  a faceface with one Ta(1)O6 octahedra,  a faceface with one Ta(2)O6 octahedra, and  a faceface with one Ta(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-55°. In the second Ba site, Ba(2) is bonded to one O(10), one O(11), one O(12), one O(13), one O(14), one O(15), one O(16), one O(17), one O(18), one O(22), one O(23), and one O(24) atom to form distorted BaO12 cuboctahedra that share  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra, corners with three equivalent Ta(7)O6 octahedra, edges with three equivalent Ba(1)O12 cuboctahedra,  an edgeedge with one Ta(1)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra,  an edgeedge with one Ta(11)O5 square pyramid,  an edgeedge with one Ta(12)O5 square pyramid,  an edgeedge with one Ta(13)O5 square pyramid,  a faceface with one Ta(4)O6 octahedra,  a faceface with one Ta(5)O6 octahedra, and  a faceface with one Ta(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-55°. There are fifteen inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(13), one O(14), one O(19), one O(27), one O(31), and one O(7) atom to form TaO6 octahedra that share  a cornercorner with one Ba(1)O12 cuboctahedra,  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra,  an edgeedge with one Ta(2)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 39-42°. In the second Ta site, Ta(2) is bonded to one O(14), one O(15), one O(20), one O(25), one O(31), and one O(8) atom to form TaO6 octahedra that share  a cornercorner with one Ba(1)O12 cuboctahedra,  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra,  an edgeedge with one Ta(1)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 39-42°. In the third Ta site, Ta(3) is bonded to one O(13), one O(15), one O(21), one O(26), one O(31), and one O(9) atom to form TaO6 octahedra that share  a cornercorner with one Ba(1)O12 cuboctahedra,  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra,  an edgeedge with one Ta(1)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 39-42°. In the fourth Ta site, Ta(4) is bonded to one O(10), one O(16), one O(17), one O(22), one O(30), and one O(32) atom to form TaO6 octahedra that share  a cornercorner with one Ba(2)O12 cuboctahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra,  an edgeedge with one Ta(5)O6 octahedra,  an edgeedge with one Ta(6)O6 octahedra, and  a faceface with one Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 39-42°. In the fifth Ta site, Ta(5) is bonded to one O(11), one O(17), one O(18), one O(23), one O(28), and one O(32) atom to form TaO6 octahedra that share  a cornercorner with one Ba(2)O12 cuboctahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra,  an edgeedge with one Ta(4)O6 octahedra,  an edgeedge with one Ta(6)O6 octahedra, and  a faceface with one Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 40-42°. In the sixth Ta site, Ta(6) is bonded to one O(12), one O(16), one O(18), one O(24), one O(29), and one O(32) atom to form TaO6 octahedra that share  a cornercorner with one Ba(2)O12 cuboctahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra,  an edgeedge with one Ta(4)O6 octahedra,  an edgeedge with one Ta(5)O6 octahedra, and  a faceface with one Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 38-43°. In the seventh Ta site, Ta(7) is bonded to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom to form TaO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Ba(2)O12 cuboctahedra,  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra, and  a cornercorner with one Ta(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-40°. In the eighth Ta site, Ta(8) is bonded to one O(19), one O(21), one O(25), one O(3), and one O(5) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra, and  an edgeedge with one Ta(14)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-53°. In the ninth Ta site, Ta(9) is bonded to one O(1), one O(19), one O(20), one O(26), and one O(6) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra, and  an edgeedge with one Ta(14)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-53°. In the tenth Ta site, Ta(10) is bonded to one O(2), one O(20), one O(21), one O(27), and one O(4) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra, and  an edgeedge with one Ta(14)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-54°. In the eleventh Ta site, Ta(11) is bonded to one O(2), one O(22), one O(24), one O(28), and one O(6) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra, and  an edgeedge with one Ta(15)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-54°. In the twelfth Ta site, Ta(12) is bonded to one O(22), one O(23), one O(29), one O(3), and one O(4) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra, and  an edgeedge with one Ta(15)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-53°. In the thirteenth Ta site, Ta(13) is bonded to one O(1), one O(23), one O(24), one O(30), and one O(5) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra, and  an edgeedge with one Ta(15)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-53°. In the fourteenth Ta site, Ta(14) is bonded to one O(25), one O(26), one O(27), one O(4), one O(5), and one O(6) atom to form TaO6 octahedra that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  an edgeedge with one Ta(10)O5 square pyramid,  an edgeedge with one Ta(8)O5 square pyramid, and  an edgeedge with one Ta(9)O5 square pyramid. The corner-sharing octahedral tilt angles are 42°. In the fifteenth Ta site, Ta(15) is bonded to one O(1), one O(2), one O(28), one O(29), one O(3), and one O(30) atom to form TaO6 octahedra that share  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ta(11)O5 square pyramid,  an edgeedge with one Ta(12)O5 square pyramid, and  an edgeedge with one Ta(13)O5 square pyramid. The corner-sharing octahedral tilt angles range from 42-43°. There are thirty-two inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Ta(13), one Ta(15), and one Ta(9) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Ta(10), one Ta(11), and one Ta(15) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Ta(12), one Ta(15), and one Ta(8) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Ta(10), one Ta(12), and one Ta(14) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Ta(13), one Ta(14), and one Ta(8) atom. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Ta(11), one Ta(14), and one Ta(9) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Ta(1), and one Ta(7) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Ta(2), and one Ta(7) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Ta(3), and one Ta(7) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Ta(4), and one Ta(7) atom. In the eleventh O site, O(11) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Ta(5), and one Ta(7) atom. In the twelfth O site, O(12) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Ta(6), and one Ta(7) atom. In the thirteenth O site, O(13) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(1), and one Ta(3) atom. In the fourteenth O site, O(14) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(1), and one Ta(2) atom. In the fifteenth O site, O(15) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(2), and one Ta(3) atom. In the sixteenth O site, O(16) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(4), and one Ta(6) atom. In the seventeenth O site, O(17) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(4), and one Ta(5) atom. In the eighteenth O site, O(18) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(5), and one Ta(6) atom. In the nineteenth O site, O(19) is bonded in a 3-coordinate geometry to one Ba(1), one Ta(1), one Ta(8), and one Ta(9) atom. In the twentieth O site, O(20) is bonded in a 3-coordinate geometry to one Ba(1), one Ta(10), one Ta(2), and one Ta(9) atom. In the twenty-first O site, O(21) is bonded in a 3-coordinate geometry to one Ba(1), one Ta(10), one Ta(3), and one Ta(8) atom. In the twenty-second O site, O(22) is bonded in a 3-coordinate geometry to one Ba(2), one Ta(11), one Ta(12), and one Ta(4) atom. In the twenty-third O site, O(23) is bonded in a 3-coordinate geometry to one Ba(2), one Ta(12), one Ta(13), and one Ta(5) atom. In the twenty-fourth O site, O(24) is bonded in a 3-coordinate geometry to one Ba(2), one Ta(11), one Ta(13), and one Ta(6) atom. In the twenty-fifth O site, O(25) is bonded in a distorted trigonal planar geometry to one Ta(14), one Ta(2), and one Ta(8) atom. In the twenty-sixth O site, O(26) is bonded in a distorted trigonal planar geometry to one Ta(14), one Ta(3), and one Ta(9) atom. In the twenty-seventh O site, O(27) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(10), and one Ta(14) atom. In the twenty-eighth O site, O(28) is bonded in a distorted trigonal planar geometry to one Ta(11), one Ta(15), and one Ta(5) atom. In the twenty-ninth O site, O(29) is bonded in a distorted trigonal planar geometry to one Ta(12), one Ta(15), and one Ta(6) atom. In the thirtieth O site, O(30) is bonded in a distorted trigonal planar geometry to one Ta(13), one Ta(15), and one Ta(4) atom. In the thirty-first O site, O(31) is bonded in a distorted trigonal non-coplanar geometry to one Ta(1), one Ta(2), and one Ta(3) atom. In the thirty-second O site, O(32) is bonded in a distorted trigonal non-coplanar geometry to one Ta(4), one Ta(5), and one Ta(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Ta15O32
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.865
_cell_length_b   7.866
_cell_length_c   12.814
_cell_angle_alpha   72.156
_cell_angle_beta   72.139
_cell_angle_gamma   60.031
_symmetry_Int_Tables_number   1
_cell_volume   642.243
_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  0.851  0.874  0.418  1.0
  Ba  Ba1  1  0.143  0.150  0.582  1.0
  Ta  Ta2  1  0.426  0.306  0.297  1.0
  Ta  Ta3  1  0.971  0.427  0.298  1.0
  Ta  Ta4  1  0.304  0.971  0.298  1.0
  Ta  Ta5  1  0.573  0.695  0.703  1.0
  Ta  Ta6  1  0.029  0.575  0.702  1.0
  Ta  Ta7  1  0.696  0.030  0.703  1.0
  Ta  Ta8  1  0.500  0.501  0.500  1.0
  Ta  Ta9  1  0.944  0.183  0.097  1.0
  Ta  Ta10  1  0.775  0.944  0.097  1.0
  Ta  Ta11  1  0.183  0.776  0.097  1.0
  Ta  Ta12  1  0.056  0.817  0.903  1.0
  Ta  Ta13  1  0.225  0.056  0.903  1.0
  Ta  Ta14  1  0.817  0.225  0.903  1.0
  Ta  Ta15  1  0.639  0.639  0.084  1.0
  Ta  Ta16  1  0.361  0.361  0.916  1.0
  O  O17  1  0.572  0.167  0.001  1.0
  O  O18  1  0.261  0.572  0.001  1.0
  O  O19  1  0.167  0.261  0.001  1.0
  O  O20  1  0.428  0.833  0.999  1.0
  O  O21  1  0.739  0.428  0.999  1.0
  O  O22  1  0.834  0.739  0.999  1.0
  O  O23  1  0.543  0.316  0.405  1.0
  O  O24  1  0.735  0.543  0.405  1.0
  O  O25  1  0.317  0.735  0.405  1.0
  O  O26  1  0.457  0.683  0.595  1.0
  O  O27  1  0.264  0.456  0.595  1.0
  O  O28  1  0.683  0.265  0.595  1.0
  O  O29  1  0.441  0.032  0.379  1.0
  O  O30  1  0.148  0.441  0.379  1.0
  O  O31  1  0.032  0.148  0.379  1.0
  O  O32  1  0.559  0.969  0.621  1.0
  O  O33  1  0.852  0.559  0.621  1.0
  O  O34  1  0.968  0.852  0.621  1.0
  O  O35  1  0.697  0.136  0.206  1.0
  O  O36  1  0.961  0.697  0.206  1.0
  O  O37  1  0.136  0.961  0.206  1.0
  O  O38  1  0.303  0.864  0.794  1.0
  O  O39  1  0.039  0.303  0.794  1.0
  O  O40  1  0.864  0.040  0.794  1.0
  O  O41  1  0.841  0.428  0.188  1.0
  O  O42  1  0.543  0.841  0.188  1.0
  O  O43  1  0.428  0.543  0.188  1.0
  O  O44  1  0.159  0.572  0.812  1.0
  O  O45  1  0.457  0.159  0.812  1.0
  O  O46  1  0.572  0.457  0.812  1.0
  O  O47  1  0.262  0.262  0.213  1.0
  O  O48  1  0.738  0.738  0.787  1.0
[/CIF]
.
The material structure described by Ba2Ta15O32 crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one O(13), one O(14), one O(15), one O(16), one O(17), one O(18), one O(19), one O(20), one O(21), one O(7), one O(8), and one O(9) atom to form distorted BaO12 cuboctahedra that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra, corners with three equivalent Ta(7)O6 octahedra, edges with three equivalent Ba(2)O12 cuboctahedra,  an edgeedge with one Ta(4)O6 octahedra,  an edgeedge with one Ta(5)O6 octahedra,  an edgeedge with one Ta(6)O6 octahedra,  an edgeedge with one Ta(10)O5 square pyramid,  an edgeedge with one Ta(8)O5 square pyramid,  an edgeedge with one Ta(9)O5 square pyramid,  a faceface with one Ta(1)O6 octahedra,  a faceface with one Ta(2)O6 octahedra, and  a faceface with one Ta(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-55°. In the second Ba site, Ba(2) is bonded to one O(10), one O(11), one O(12), one O(13), one O(14), one O(15), one O(16), one O(17), one O(18), one O(22), one O(23), and one O(24) atom to form distorted BaO12 cuboctahedra that share  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra, corners with three equivalent Ta(7)O6 octahedra, edges with three equivalent Ba(1)O12 cuboctahedra,  an edgeedge with one Ta(1)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra,  an edgeedge with one Ta(11)O5 square pyramid,  an edgeedge with one Ta(12)O5 square pyramid,  an edgeedge with one Ta(13)O5 square pyramid,  a faceface with one Ta(4)O6 octahedra,  a faceface with one Ta(5)O6 octahedra, and  a faceface with one Ta(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-55°. There are fifteen inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(13), one O(14), one O(19), one O(27), one O(31), and one O(7) atom to form TaO6 octahedra that share  a cornercorner with one Ba(1)O12 cuboctahedra,  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra,  an edgeedge with one Ta(2)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 39-42°. In the second Ta site, Ta(2) is bonded to one O(14), one O(15), one O(20), one O(25), one O(31), and one O(8) atom to form TaO6 octahedra that share  a cornercorner with one Ba(1)O12 cuboctahedra,  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra,  an edgeedge with one Ta(1)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 39-42°. In the third Ta site, Ta(3) is bonded to one O(13), one O(15), one O(21), one O(26), one O(31), and one O(9) atom to form TaO6 octahedra that share  a cornercorner with one Ba(1)O12 cuboctahedra,  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra,  an edgeedge with one Ta(1)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 39-42°. In the fourth Ta site, Ta(4) is bonded to one O(10), one O(16), one O(17), one O(22), one O(30), and one O(32) atom to form TaO6 octahedra that share  a cornercorner with one Ba(2)O12 cuboctahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra,  an edgeedge with one Ta(5)O6 octahedra,  an edgeedge with one Ta(6)O6 octahedra, and  a faceface with one Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 39-42°. In the fifth Ta site, Ta(5) is bonded to one O(11), one O(17), one O(18), one O(23), one O(28), and one O(32) atom to form TaO6 octahedra that share  a cornercorner with one Ba(2)O12 cuboctahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra,  an edgeedge with one Ta(4)O6 octahedra,  an edgeedge with one Ta(6)O6 octahedra, and  a faceface with one Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 40-42°. In the sixth Ta site, Ta(6) is bonded to one O(12), one O(16), one O(18), one O(24), one O(29), and one O(32) atom to form TaO6 octahedra that share  a cornercorner with one Ba(2)O12 cuboctahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(7)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra,  an edgeedge with one Ta(4)O6 octahedra,  an edgeedge with one Ta(5)O6 octahedra, and  a faceface with one Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 38-43°. In the seventh Ta site, Ta(7) is bonded to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom to form TaO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Ba(2)O12 cuboctahedra,  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra, and  a cornercorner with one Ta(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-40°. In the eighth Ta site, Ta(8) is bonded to one O(19), one O(21), one O(25), one O(3), and one O(5) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra, and  an edgeedge with one Ta(14)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-53°. In the ninth Ta site, Ta(9) is bonded to one O(1), one O(19), one O(20), one O(26), and one O(6) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra, and  an edgeedge with one Ta(14)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-53°. In the tenth Ta site, Ta(10) is bonded to one O(2), one O(20), one O(21), one O(27), and one O(4) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(15)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(1)O12 cuboctahedra, and  an edgeedge with one Ta(14)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-54°. In the eleventh Ta site, Ta(11) is bonded to one O(2), one O(22), one O(24), one O(28), and one O(6) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra, and  an edgeedge with one Ta(15)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-54°. In the twelfth Ta site, Ta(12) is bonded to one O(22), one O(23), one O(29), one O(3), and one O(4) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra, and  an edgeedge with one Ta(15)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-53°. In the thirteenth Ta site, Ta(13) is bonded to one O(1), one O(23), one O(24), one O(30), and one O(5) atom to form TaO5 square pyramids that share  a cornercorner with one Ta(14)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ba(2)O12 cuboctahedra, and  an edgeedge with one Ta(15)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-53°. In the fourteenth Ta site, Ta(14) is bonded to one O(25), one O(26), one O(27), one O(4), one O(5), and one O(6) atom to form TaO6 octahedra that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(11)O5 square pyramid,  a cornercorner with one Ta(12)O5 square pyramid,  a cornercorner with one Ta(13)O5 square pyramid,  an edgeedge with one Ta(10)O5 square pyramid,  an edgeedge with one Ta(8)O5 square pyramid, and  an edgeedge with one Ta(9)O5 square pyramid. The corner-sharing octahedral tilt angles are 42°. In the fifteenth Ta site, Ta(15) is bonded to one O(1), one O(2), one O(28), one O(29), one O(3), and one O(30) atom to form TaO6 octahedra that share  a cornercorner with one Ta(4)O6 octahedra,  a cornercorner with one Ta(5)O6 octahedra,  a cornercorner with one Ta(6)O6 octahedra,  a cornercorner with one Ta(10)O5 square pyramid,  a cornercorner with one Ta(8)O5 square pyramid,  a cornercorner with one Ta(9)O5 square pyramid,  an edgeedge with one Ta(11)O5 square pyramid,  an edgeedge with one Ta(12)O5 square pyramid, and  an edgeedge with one Ta(13)O5 square pyramid. The corner-sharing octahedral tilt angles range from 42-43°. There are thirty-two inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Ta(13), one Ta(15), and one Ta(9) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Ta(10), one Ta(11), and one Ta(15) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Ta(12), one Ta(15), and one Ta(8) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Ta(10), one Ta(12), and one Ta(14) atom. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Ta(13), one Ta(14), and one Ta(8) atom. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Ta(11), one Ta(14), and one Ta(9) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Ta(1), and one Ta(7) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Ta(2), and one Ta(7) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Ba(1), one Ta(3), and one Ta(7) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Ta(4), and one Ta(7) atom. In the eleventh O site, O(11) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Ta(5), and one Ta(7) atom. In the twelfth O site, O(12) is bonded in a distorted bent 150 degrees geometry to one Ba(2), one Ta(6), and one Ta(7) atom. In the thirteenth O site, O(13) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(1), and one Ta(3) atom. In the fourteenth O site, O(14) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(1), and one Ta(2) atom. In the fifteenth O site, O(15) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(2), and one Ta(3) atom. In the sixteenth O site, O(16) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(4), and one Ta(6) atom. In the seventeenth O site, O(17) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(4), and one Ta(5) atom. In the eighteenth O site, O(18) is bonded in a distorted water-like geometry to one Ba(1), one Ba(2), one Ta(5), and one Ta(6) atom. In the nineteenth O site, O(19) is bonded in a 3-coordinate geometry to one Ba(1), one Ta(1), one Ta(8), and one Ta(9) atom. In the twentieth O site, O(20) is bonded in a 3-coordinate geometry to one Ba(1), one Ta(10), one Ta(2), and one Ta(9) atom. In the twenty-first O site, O(21) is bonded in a 3-coordinate geometry to one Ba(1), one Ta(10), one Ta(3), and one Ta(8) atom. In the twenty-second O site, O(22) is bonded in a 3-coordinate geometry to one Ba(2), one Ta(11), one Ta(12), and one Ta(4) atom. In the twenty-third O site, O(23) is bonded in a 3-coordinate geometry to one Ba(2), one Ta(12), one Ta(13), and one Ta(5) atom. In the twenty-fourth O site, O(24) is bonded in a 3-coordinate geometry to one Ba(2), one Ta(11), one Ta(13), and one Ta(6) atom. In the twenty-fifth O site, O(25) is bonded in a distorted trigonal planar geometry to one Ta(14), one Ta(2), and one Ta(8) atom. In the twenty-sixth O site, O(26) is bonded in a distorted trigonal planar geometry to one Ta(14), one Ta(3), and one Ta(9) atom. In the twenty-seventh O site, O(27) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(10), and one Ta(14) atom. In the twenty-eighth O site, O(28) is bonded in a distorted trigonal planar geometry to one Ta(11), one Ta(15), and one Ta(5) atom. In the twenty-ninth O site, O(29) is bonded in a distorted trigonal planar geometry to one Ta(12), one Ta(15), and one Ta(6) atom. In the thirtieth O site, O(30) is bonded in a distorted trigonal planar geometry to one Ta(13), one Ta(15), and one Ta(4) atom. In the thirty-first O site, O(31) is bonded in a distorted trigonal non-coplanar geometry to one Ta(1), one Ta(2), and one Ta(3) atom. In the thirty-second O site, O(32) is bonded in a distorted trigonal non-coplanar geometry to one Ta(4), one Ta(5), and one Ta(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Ta15O32
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.865
_cell_length_b   7.866
_cell_length_c   12.814
_cell_angle_alpha   72.156
_cell_angle_beta   72.139
_cell_angle_gamma   60.031
_symmetry_Int_Tables_number   1
_cell_volume   642.243
_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  0.851  0.874  0.418  1.0
  Ba  Ba1  1  0.143  0.150  0.582  1.0
  Ta  Ta2  1  0.426  0.306  0.297  1.0
  Ta  Ta3  1  0.971  0.427  0.298  1.0
  Ta  Ta4  1  0.304  0.971  0.298  1.0
  Ta  Ta5  1  0.573  0.695  0.703  1.0
  Ta  Ta6  1  0.029  0.575  0.702  1.0
  Ta  Ta7  1  0.696  0.030  0.703  1.0
  Ta  Ta8  1  0.500  0.501  0.500  1.0
  Ta  Ta9  1  0.944  0.183  0.097  1.0
  Ta  Ta10  1  0.775  0.944  0.097  1.0
  Ta  Ta11  1  0.183  0.776  0.097  1.0
  Ta  Ta12  1  0.056  0.817  0.903  1.0
  Ta  Ta13  1  0.225  0.056  0.903  1.0
  Ta  Ta14  1  0.817  0.225  0.903  1.0
  Ta  Ta15  1  0.639  0.639  0.084  1.0
  Ta  Ta16  1  0.361  0.361  0.916  1.0
  O  O17  1  0.572  0.167  0.001  1.0
  O  O18  1  0.261  0.572  0.001  1.0
  O  O19  1  0.167  0.261  0.001  1.0
  O  O20  1  0.428  0.833  0.999  1.0
  O  O21  1  0.739  0.428  0.999  1.0
  O  O22  1  0.834  0.739  0.999  1.0
  O  O23  1  0.543  0.316  0.405  1.0
  O  O24  1  0.735  0.543  0.405  1.0
  O  O25  1  0.317  0.735  0.405  1.0
  O  O26  1  0.457  0.683  0.595  1.0
  O  O27  1  0.264  0.456  0.595  1.0
  O  O28  1  0.683  0.265  0.595  1.0
  O  O29  1  0.441  0.032  0.379  1.0
  O  O30  1  0.148  0.441  0.379  1.0
  O  O31  1  0.032  0.148  0.379  1.0
  O  O32  1  0.559  0.969  0.621  1.0
  O  O33  1  0.852  0.559  0.621  1.0
  O  O34  1  0.968  0.852  0.621  1.0
  O  O35  1  0.697  0.136  0.206  1.0
  O  O36  1  0.961  0.697  0.206  1.0
  O  O37  1  0.136  0.961  0.206  1.0
  O  O38  1  0.303  0.864  0.794  1.0
  O  O39  1  0.039  0.303  0.794  1.0
  O  O40  1  0.864  0.040  0.794  1.0
  O  O41  1  0.841  0.428  0.188  1.0
  O  O42  1  0.543  0.841  0.188  1.0
  O  O43  1  0.428  0.543  0.188  1.0
  O  O44  1  0.159  0.572  0.812  1.0
  O  O45  1  0.457  0.159  0.812  1.0
  O  O46  1  0.572  0.457  0.812  1.0
  O  O47  1  0.262  0.262  0.213  1.0
  O  O48  1  0.738  0.738  0.787  1.0
[/CIF]
.