The compound described by Ba3HfTa4O15 crystallizes in the monoclinic Pc space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(5), one O(6), one O(9), two equivalent O(1), two equivalent O(14), and two equivalent O(4) atoms. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to two equivalent O(15), two equivalent O(2), and two equivalent O(3) atoms. In the third Ba site, Ba(3) is bonded to one O(6), one O(7), one O(8), one O(9), two equivalent O(10), two equivalent O(11), two equivalent O(12), and two equivalent O(13) atoms to form BaO12 cuboctahedra that share faces with two equivalent Ba(3)O12 cuboctahedra, faces with two equivalent Hf(1)O6 octahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, and faces with two equivalent Ta(3)O6 octahedra. Hf(1) is bonded to one O(10), one O(12), one O(14), one O(3), and two equivalent O(6) atoms to form HfO6 octahedra that share  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Hf(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Ba(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 4-46°. There are four inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(11), one O(13), one O(15), one O(4), and two equivalent O(7) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, and faces with two equivalent Ba(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-36°. In the second Ta site, Ta(2) is bonded to one O(11), one O(12), one O(15), one O(2), and two equivalent O(8) atoms to form TaO6 octahedra that share  a cornercorner with one Hf(1)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, and faces with two equivalent Ba(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-36°. In the third Ta site, Ta(3) is bonded to one O(1), one O(10), one O(13), one O(14), and two equivalent O(9) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Hf(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Ba(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-46°. In the fourth Ta site, Ta(4) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share  a cornercorner with one Hf(1)O6 octahedra,  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra, and corners with two equivalent Ta(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-40°. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1), one Ta(3), and one Ta(4) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(2), one Ta(2), and one Ta(4) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Ba(2), one Hf(1), and one Ta(4) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1), one Ta(1), and one Ta(4) atom. In the fifth O site, O(5) is bonded in a distorted linear geometry to one Ba(1) and two equivalent Ta(4) atoms. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(3), and two equivalent Hf(1) atoms. In the seventh O site, O(7) is bonded in a distorted linear geometry to one Ba(3) and two equivalent Ta(1) atoms. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Ba(3) and two equivalent Ta(2) atoms. In the ninth O site, O(9) is bonded in a distorted linear geometry to one Ba(1), one Ba(3), and two equivalent Ta(3) atoms. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to two equivalent Ba(3), one Hf(1), and one Ta(3) atom. In the eleventh O site, O(11) is bonded in a distorted linear geometry to two equivalent Ba(3), one Ta(1), and one Ta(2) atom. In the twelfth O site, O(12) is bonded in a distorted linear geometry to two equivalent Ba(3), one Hf(1), and one Ta(2) atom. In the thirteenth O site, O(13) is bonded in a distorted linear geometry to two equivalent Ba(3), one Ta(1), and one Ta(3) atom. In the fourteenth O site, O(14) is bonded to two equivalent Ba(1), one Hf(1), and one Ta(3) atom to form distorted corner-sharing OBa2HfTa tetrahedra. In the fifteenth O site, O(15) is bonded in a 4-coordinate geometry to two equivalent Ba(2), one Ta(1), and one Ta(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3HfTa4O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.027
_cell_length_b   12.832
_cell_length_c   12.829
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   89.879
_symmetry_Int_Tables_number   1
_cell_volume   662.923
_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
  Ba  Ba0  1  0.623  0.828  0.326  1.0
  Ba  Ba1  1  0.621  0.169  0.673  1.0
  Ba  Ba2  1  0.621  0.669  0.827  1.0
  Ba  Ba3  1  0.623  0.328  0.174  1.0
  Ba  Ba4  1  0.617  0.496  0.499  1.0
  Ba  Ba5  1  0.617  0.996  0.001  1.0
  Hf  Hf6  1  0.121  0.282  0.421  1.0
  Hf  Hf7  1  0.121  0.782  0.079  1.0
  Ta  Ta8  1  0.111  0.711  0.575  1.0
  Ta  Ta9  1  0.111  0.211  0.925  1.0
  Ta  Ta10  1  0.112  0.422  0.711  1.0
  Ta  Ta11  1  0.111  0.574  0.287  1.0
  Ta  Ta12  1  0.112  0.922  0.789  1.0
  Ta  Ta13  1  0.111  0.074  0.213  1.0
  Ta  Ta14  1  0.144  0.000  0.502  1.0
  Ta  Ta15  1  0.144  0.500  0.998  1.0
  O  O16  1  0.117  0.500  0.155  1.0
  O  O17  1  0.119  0.502  0.844  1.0
  O  O18  1  0.119  0.002  0.656  1.0
  O  O19  1  0.117  1.000  0.345  1.0
  O  O20  1  0.115  0.153  0.513  1.0
  O  O21  1  0.116  0.843  0.498  1.0
  O  O22  1  0.115  0.653  0.987  1.0
  O  O23  1  0.116  0.343  0.002  1.0
  O  O24  1  0.619  0.997  0.498  1.0
  O  O25  1  0.619  0.497  0.002  1.0
  O  O26  1  0.622  0.301  0.412  1.0
  O  O27  1  0.621  0.704  0.583  1.0
  O  O28  1  0.621  0.204  0.917  1.0
  O  O29  1  0.622  0.801  0.088  1.0
  O  O30  1  0.622  0.421  0.708  1.0
  O  O31  1  0.620  0.583  0.296  1.0
  O  O32  1  0.622  0.921  0.792  1.0
  O  O33  1  0.620  0.083  0.204  1.0
  O  O34  1  0.122  0.440  0.359  1.0
  O  O35  1  0.123  0.568  0.645  1.0
  O  O36  1  0.123  0.068  0.855  1.0
  O  O37  1  0.122  0.940  0.141  1.0
  O  O38  1  0.124  0.360  0.572  1.0
  O  O39  1  0.121  0.642  0.437  1.0
  O  O40  1  0.124  0.860  0.928  1.0
  O  O41  1  0.121  0.142  0.063  1.0
  O  O42  1  0.122  0.720  0.229  1.0
  O  O43  1  0.123  0.283  0.783  1.0
  O  O44  1  0.123  0.783  0.717  1.0
  O  O45  1  0.122  0.220  0.271  1.0
[/CIF]
.
The compound described by Ba3HfTa4O15 crystallizes in the monoclinic Pc space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(5), one O(6), one O(9), two equivalent O(1), two equivalent O(14), and two equivalent O(4) atoms. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to two equivalent O(15), two equivalent O(2), and two equivalent O(3) atoms. In the third Ba site, Ba(3) is bonded to one O(6), one O(7), one O(8), one O(9), two equivalent O(10), two equivalent O(11), two equivalent O(12), and two equivalent O(13) atoms to form BaO12 cuboctahedra that share faces with two equivalent Ba(3)O12 cuboctahedra, faces with two equivalent Hf(1)O6 octahedra, faces with two equivalent Ta(1)O6 octahedra, faces with two equivalent Ta(2)O6 octahedra, and faces with two equivalent Ta(3)O6 octahedra. Hf(1) is bonded to one O(10), one O(12), one O(14), one O(3), and two equivalent O(6) atoms to form HfO6 octahedra that share  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Hf(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Ba(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 4-46°. There are four inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(11), one O(13), one O(15), one O(4), and two equivalent O(7) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(3)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, and faces with two equivalent Ba(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-36°. In the second Ta site, Ta(2) is bonded to one O(11), one O(12), one O(15), one O(2), and two equivalent O(8) atoms to form TaO6 octahedra that share  a cornercorner with one Hf(1)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, and faces with two equivalent Ba(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-36°. In the third Ta site, Ta(3) is bonded to one O(1), one O(10), one O(13), one O(14), and two equivalent O(9) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(4)O6 octahedra, corners with two equivalent Hf(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, and faces with two equivalent Ba(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-46°. In the fourth Ta site, Ta(4) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share  a cornercorner with one Hf(1)O6 octahedra,  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  a cornercorner with one Ta(3)O6 octahedra, and corners with two equivalent Ta(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-40°. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1), one Ta(3), and one Ta(4) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(2), one Ta(2), and one Ta(4) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Ba(2), one Hf(1), and one Ta(4) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1), one Ta(1), and one Ta(4) atom. In the fifth O site, O(5) is bonded in a distorted linear geometry to one Ba(1) and two equivalent Ta(4) atoms. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(3), and two equivalent Hf(1) atoms. In the seventh O site, O(7) is bonded in a distorted linear geometry to one Ba(3) and two equivalent Ta(1) atoms. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Ba(3) and two equivalent Ta(2) atoms. In the ninth O site, O(9) is bonded in a distorted linear geometry to one Ba(1), one Ba(3), and two equivalent Ta(3) atoms. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to two equivalent Ba(3), one Hf(1), and one Ta(3) atom. In the eleventh O site, O(11) is bonded in a distorted linear geometry to two equivalent Ba(3), one Ta(1), and one Ta(2) atom. In the twelfth O site, O(12) is bonded in a distorted linear geometry to two equivalent Ba(3), one Hf(1), and one Ta(2) atom. In the thirteenth O site, O(13) is bonded in a distorted linear geometry to two equivalent Ba(3), one Ta(1), and one Ta(3) atom. In the fourteenth O site, O(14) is bonded to two equivalent Ba(1), one Hf(1), and one Ta(3) atom to form distorted corner-sharing OBa2HfTa tetrahedra. In the fifteenth O site, O(15) is bonded in a 4-coordinate geometry to two equivalent Ba(2), one Ta(1), and one Ta(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3HfTa4O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.027
_cell_length_b   12.832
_cell_length_c   12.829
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   89.879
_symmetry_Int_Tables_number   1
_cell_volume   662.923
_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
  Ba  Ba0  1  0.623  0.828  0.326  1.0
  Ba  Ba1  1  0.621  0.169  0.673  1.0
  Ba  Ba2  1  0.621  0.669  0.827  1.0
  Ba  Ba3  1  0.623  0.328  0.174  1.0
  Ba  Ba4  1  0.617  0.496  0.499  1.0
  Ba  Ba5  1  0.617  0.996  0.001  1.0
  Hf  Hf6  1  0.121  0.282  0.421  1.0
  Hf  Hf7  1  0.121  0.782  0.079  1.0
  Ta  Ta8  1  0.111  0.711  0.575  1.0
  Ta  Ta9  1  0.111  0.211  0.925  1.0
  Ta  Ta10  1  0.112  0.422  0.711  1.0
  Ta  Ta11  1  0.111  0.574  0.287  1.0
  Ta  Ta12  1  0.112  0.922  0.789  1.0
  Ta  Ta13  1  0.111  0.074  0.213  1.0
  Ta  Ta14  1  0.144  0.000  0.502  1.0
  Ta  Ta15  1  0.144  0.500  0.998  1.0
  O  O16  1  0.117  0.500  0.155  1.0
  O  O17  1  0.119  0.502  0.844  1.0
  O  O18  1  0.119  0.002  0.656  1.0
  O  O19  1  0.117  1.000  0.345  1.0
  O  O20  1  0.115  0.153  0.513  1.0
  O  O21  1  0.116  0.843  0.498  1.0
  O  O22  1  0.115  0.653  0.987  1.0
  O  O23  1  0.116  0.343  0.002  1.0
  O  O24  1  0.619  0.997  0.498  1.0
  O  O25  1  0.619  0.497  0.002  1.0
  O  O26  1  0.622  0.301  0.412  1.0
  O  O27  1  0.621  0.704  0.583  1.0
  O  O28  1  0.621  0.204  0.917  1.0
  O  O29  1  0.622  0.801  0.088  1.0
  O  O30  1  0.622  0.421  0.708  1.0
  O  O31  1  0.620  0.583  0.296  1.0
  O  O32  1  0.622  0.921  0.792  1.0
  O  O33  1  0.620  0.083  0.204  1.0
  O  O34  1  0.122  0.440  0.359  1.0
  O  O35  1  0.123  0.568  0.645  1.0
  O  O36  1  0.123  0.068  0.855  1.0
  O  O37  1  0.122  0.940  0.141  1.0
  O  O38  1  0.124  0.360  0.572  1.0
  O  O39  1  0.121  0.642  0.437  1.0
  O  O40  1  0.124  0.860  0.928  1.0
  O  O41  1  0.121  0.142  0.063  1.0
  O  O42  1  0.122  0.720  0.229  1.0
  O  O43  1  0.123  0.283  0.783  1.0
  O  O44  1  0.123  0.783  0.717  1.0
  O  O45  1  0.122  0.220  0.271  1.0
[/CIF]
.