The material structure described by Ba3CaSb2O9 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(5), and four equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to one O(5), two equivalent O(1), three equivalent O(2), three equivalent O(3), and three equivalent O(4) atoms. Ca(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form CaO6 octahedra that share corners with six equivalent Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-22°. Sb(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form SbO6 octahedra that share corners with three equivalent Ca(1)O6 octahedra and  a faceface with one Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-22°. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted L-shaped geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sb(1) atoms. In the second O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sb(1) atoms. In the third O site, O(2) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Ca(1), and one Sb(1) atom. In the fourth O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Ca(1), and one Sb(1) atom. In the fifth O site, O(4) is bonded in a 2-coordinate geometry to three equivalent Ba(2), one Ca(1), and one Sb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3CaSb2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.086
_cell_length_b   6.086
_cell_length_c   15.075
_cell_angle_alpha   88.967
_cell_angle_beta   88.967
_cell_angle_gamma   119.804
_symmetry_Int_Tables_number   1
_cell_volume   484.257
_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  0.010  0.990  0.250  1.0
  Ba  Ba1  1  0.339  0.677  0.910  1.0
  Ba  Ba2  1  0.323  0.661  0.590  1.0
  Ba  Ba3  1  0.677  0.339  0.410  1.0
  Ba  Ba4  1  0.661  0.323  0.090  1.0
  Ba  Ba5  1  0.990  0.010  0.750  1.0
  Ca  Ca6  1  0.000  0.000  0.000  1.0
  Ca  Ca7  1  0.000  0.000  0.500  1.0
  Sb  Sb8  1  0.317  0.642  0.155  1.0
  Sb  Sb9  1  0.642  0.317  0.655  1.0
  Sb  Sb10  1  0.358  0.683  0.345  1.0
  Sb  Sb11  1  0.683  0.358  0.845  1.0
  O  O12  1  0.951  0.479  0.736  1.0
  O  O13  1  0.137  0.781  0.088  1.0
  O  O14  1  0.781  0.137  0.588  1.0
  O  O15  1  0.869  0.695  0.895  1.0
  O  O16  1  0.049  0.521  0.264  1.0
  O  O17  1  0.131  0.305  0.105  1.0
  O  O18  1  0.479  0.951  0.236  1.0
  O  O19  1  0.227  0.390  0.428  1.0
  O  O20  1  0.517  0.483  0.750  1.0
  O  O21  1  0.610  0.773  0.072  1.0
  O  O22  1  0.695  0.869  0.395  1.0
  O  O23  1  0.863  0.219  0.912  1.0
  O  O24  1  0.521  0.049  0.764  1.0
  O  O25  1  0.390  0.227  0.928  1.0
  O  O26  1  0.773  0.610  0.572  1.0
  O  O27  1  0.305  0.131  0.605  1.0
  O  O28  1  0.219  0.863  0.412  1.0
  O  O29  1  0.483  0.517  0.250  1.0
[/CIF]
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The material structure described by Ba3CaSb2O9 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(5), and four equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to one O(5), two equivalent O(1), three equivalent O(2), three equivalent O(3), and three equivalent O(4) atoms. Ca(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form CaO6 octahedra that share corners with six equivalent Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-22°. Sb(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form SbO6 octahedra that share corners with three equivalent Ca(1)O6 octahedra and  a faceface with one Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-22°. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted L-shaped geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sb(1) atoms. In the second O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sb(1) atoms. In the third O site, O(2) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Ca(1), and one Sb(1) atom. In the fourth O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Ca(1), and one Sb(1) atom. In the fifth O site, O(4) is bonded in a 2-coordinate geometry to three equivalent Ba(2), one Ca(1), and one Sb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3CaSb2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.086
_cell_length_b   6.086
_cell_length_c   15.075
_cell_angle_alpha   88.967
_cell_angle_beta   88.967
_cell_angle_gamma   119.804
_symmetry_Int_Tables_number   1
_cell_volume   484.257
_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  0.010  0.990  0.250  1.0
  Ba  Ba1  1  0.339  0.677  0.910  1.0
  Ba  Ba2  1  0.323  0.661  0.590  1.0
  Ba  Ba3  1  0.677  0.339  0.410  1.0
  Ba  Ba4  1  0.661  0.323  0.090  1.0
  Ba  Ba5  1  0.990  0.010  0.750  1.0
  Ca  Ca6  1  0.000  0.000  0.000  1.0
  Ca  Ca7  1  0.000  0.000  0.500  1.0
  Sb  Sb8  1  0.317  0.642  0.155  1.0
  Sb  Sb9  1  0.642  0.317  0.655  1.0
  Sb  Sb10  1  0.358  0.683  0.345  1.0
  Sb  Sb11  1  0.683  0.358  0.845  1.0
  O  O12  1  0.951  0.479  0.736  1.0
  O  O13  1  0.137  0.781  0.088  1.0
  O  O14  1  0.781  0.137  0.588  1.0
  O  O15  1  0.869  0.695  0.895  1.0
  O  O16  1  0.049  0.521  0.264  1.0
  O  O17  1  0.131  0.305  0.105  1.0
  O  O18  1  0.479  0.951  0.236  1.0
  O  O19  1  0.227  0.390  0.428  1.0
  O  O20  1  0.517  0.483  0.750  1.0
  O  O21  1  0.610  0.773  0.072  1.0
  O  O22  1  0.695  0.869  0.395  1.0
  O  O23  1  0.863  0.219  0.912  1.0
  O  O24  1  0.521  0.049  0.764  1.0
  O  O25  1  0.390  0.227  0.928  1.0
  O  O26  1  0.773  0.610  0.572  1.0
  O  O27  1  0.305  0.131  0.605  1.0
  O  O28  1  0.219  0.863  0.412  1.0
  O  O29  1  0.483  0.517  0.250  1.0
[/CIF]
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