The compound described by BaCa3 is alpha La-derived structured and crystallizes in the trigonal R-3m space group. Ba(1) is bonded to six equivalent Ba(1) and six equivalent Ca(1) atoms to form BaBa6Ca6 cuboctahedra that share corners with six equivalent Ba(1)Ba6Ca6 cuboctahedra, corners with six equivalent Ca(2)Ca12 cuboctahedra, edges with six equivalent Ba(1)Ba6Ca6 cuboctahedra, edges with six equivalent Ca(2)Ca12 cuboctahedra, edges with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra, faces with six equivalent Ba(1)Ba6Ca6 cuboctahedra, and faces with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to three equivalent Ba(1), three equivalent Ca(2), and six equivalent Ca(1) atoms to form CaBa3Ca9 cuboctahedra that share corners with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra, edges with six equivalent Ba(1)Ba6Ca6 cuboctahedra, edges with six equivalent Ca(2)Ca12 cuboctahedra, edges with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra, faces with six equivalent Ba(1)Ba6Ca6 cuboctahedra, faces with six equivalent Ca(1)Ba3Ca9 cuboctahedra, and faces with six equivalent Ca(2)Ca12 cuboctahedra. In the second Ca site, Ca(2) is bonded to six equivalent Ca(1) and six equivalent Ca(2) atoms to form CaCa12 cuboctahedra that share corners with six equivalent Ba(1)Ba6Ca6 cuboctahedra, corners with six equivalent Ca(2)Ca12 cuboctahedra, edges with six equivalent Ba(1)Ba6Ca6 cuboctahedra, edges with six equivalent Ca(2)Ca12 cuboctahedra, edges with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra, faces with six equivalent Ca(2)Ca12 cuboctahedra, and faces with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra. is represented by the CIF file [CIF]
data_BaCa3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.326
_cell_length_b   13.326
_cell_length_c   13.326
_cell_angle_alpha   17.346
_cell_angle_beta   17.346
_cell_angle_gamma   17.346
_symmetry_Int_Tables_number   1
_cell_volume   183.574
_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  0.000  0.000  0.000  1.0
  Ca  Ca1  1  0.246  0.246  0.246  1.0
  Ca  Ca2  1  0.500  0.500  0.500  1.0
  Ca  Ca3  1  0.754  0.754  0.754  1.0
[/CIF]
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The compound described by BaCa3 is alpha La-derived structured and crystallizes in the trigonal R-3m space group. Ba(1) is bonded to six equivalent Ba(1) and six equivalent Ca(1) atoms to form BaBa6Ca6 cuboctahedra that share corners with six equivalent Ba(1)Ba6Ca6 cuboctahedra, corners with six equivalent Ca(2)Ca12 cuboctahedra, edges with six equivalent Ba(1)Ba6Ca6 cuboctahedra, edges with six equivalent Ca(2)Ca12 cuboctahedra, edges with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra, faces with six equivalent Ba(1)Ba6Ca6 cuboctahedra, and faces with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to three equivalent Ba(1), three equivalent Ca(2), and six equivalent Ca(1) atoms to form CaBa3Ca9 cuboctahedra that share corners with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra, edges with six equivalent Ba(1)Ba6Ca6 cuboctahedra, edges with six equivalent Ca(2)Ca12 cuboctahedra, edges with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra, faces with six equivalent Ba(1)Ba6Ca6 cuboctahedra, faces with six equivalent Ca(1)Ba3Ca9 cuboctahedra, and faces with six equivalent Ca(2)Ca12 cuboctahedra. In the second Ca site, Ca(2) is bonded to six equivalent Ca(1) and six equivalent Ca(2) atoms to form CaCa12 cuboctahedra that share corners with six equivalent Ba(1)Ba6Ca6 cuboctahedra, corners with six equivalent Ca(2)Ca12 cuboctahedra, edges with six equivalent Ba(1)Ba6Ca6 cuboctahedra, edges with six equivalent Ca(2)Ca12 cuboctahedra, edges with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra, faces with six equivalent Ca(2)Ca12 cuboctahedra, and faces with twelve equivalent Ca(1)Ba3Ca9 cuboctahedra. is represented by the CIF file [CIF]
data_BaCa3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.326
_cell_length_b   13.326
_cell_length_c   13.326
_cell_angle_alpha   17.346
_cell_angle_beta   17.346
_cell_angle_gamma   17.346
_symmetry_Int_Tables_number   1
_cell_volume   183.574
_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  0.000  0.000  0.000  1.0
  Ca  Ca1  1  0.246  0.246  0.246  1.0
  Ca  Ca2  1  0.500  0.500  0.500  1.0
  Ca  Ca3  1  0.754  0.754  0.754  1.0
[/CIF]
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