The crystal structure described by BaCa3 crystallizes in the hexagonal P6_3/mmc space group. Ba(1) is bonded to twelve Ca(1,1) atoms to form BaCa12 cuboctahedra that share corners with six equivalent Ba(1)Ca12 cuboctahedra; corners with twelve Ca(1,1)Ba4Ca8 cuboctahedra; edges with eighteen Ca(1,1)Ba4Ca8 cuboctahedra; faces with eight equivalent Ba(1)Ca12 cuboctahedra; and faces with twelve Ca(1,1)Ba4Ca8 cuboctahedra. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four equivalent Ba(1) and eight Ca(1,1) atoms to form distorted CaBa4Ca8 cuboctahedra that share corners with four equivalent Ba(1)Ca12 cuboctahedra; corners with fourteen Ca(1,1)Ba4Ca8 cuboctahedra; edges with six equivalent Ba(1)Ca12 cuboctahedra; edges with twelve Ca(1,1)Ba4Ca8 cuboctahedra; faces with four equivalent Ba(1)Ca12 cuboctahedra; and faces with sixteen Ca(1,1)Ba4Ca8 cuboctahedra. In the second Ca site, Ca(1) is bonded to four equivalent Ba(1) and eight Ca(1,1) atoms to form distorted CaBa4Ca8 cuboctahedra that share corners with four equivalent Ba(1)Ca12 cuboctahedra; corners with fourteen Ca(1,1)Ba4Ca8 cuboctahedra; edges with six equivalent Ba(1)Ca12 cuboctahedra; edges with twelve Ca(1,1)Ba4Ca8 cuboctahedra; faces with four equivalent Ba(1)Ca12 cuboctahedra; and faces with sixteen Ca(1,1)Ba4Ca8 cuboctahedra. is represented by the CIF file [CIF]
data_BaCa3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.231
_cell_length_b   8.231
_cell_length_c   6.688
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   392.431
_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  0.333  0.667  0.750  1.0
  Ba  Ba1  1  0.667  0.333  0.250  1.0
  Ca  Ca2  1  0.161  0.323  0.250  1.0
  Ca  Ca3  1  0.677  0.839  0.250  1.0
  Ca  Ca4  1  0.161  0.839  0.250  1.0
  Ca  Ca5  1  0.839  0.677  0.750  1.0
  Ca  Ca6  1  0.323  0.161  0.750  1.0
  Ca  Ca7  1  0.839  0.161  0.750  1.0
[/CIF]
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The crystal structure described by BaCa3 crystallizes in the hexagonal P6_3/mmc space group. Ba(1) is bonded to twelve Ca(1,1) atoms to form BaCa12 cuboctahedra that share corners with six equivalent Ba(1)Ca12 cuboctahedra; corners with twelve Ca(1,1)Ba4Ca8 cuboctahedra; edges with eighteen Ca(1,1)Ba4Ca8 cuboctahedra; faces with eight equivalent Ba(1)Ca12 cuboctahedra; and faces with twelve Ca(1,1)Ba4Ca8 cuboctahedra. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to four equivalent Ba(1) and eight Ca(1,1) atoms to form distorted CaBa4Ca8 cuboctahedra that share corners with four equivalent Ba(1)Ca12 cuboctahedra; corners with fourteen Ca(1,1)Ba4Ca8 cuboctahedra; edges with six equivalent Ba(1)Ca12 cuboctahedra; edges with twelve Ca(1,1)Ba4Ca8 cuboctahedra; faces with four equivalent Ba(1)Ca12 cuboctahedra; and faces with sixteen Ca(1,1)Ba4Ca8 cuboctahedra. In the second Ca site, Ca(1) is bonded to four equivalent Ba(1) and eight Ca(1,1) atoms to form distorted CaBa4Ca8 cuboctahedra that share corners with four equivalent Ba(1)Ca12 cuboctahedra; corners with fourteen Ca(1,1)Ba4Ca8 cuboctahedra; edges with six equivalent Ba(1)Ca12 cuboctahedra; edges with twelve Ca(1,1)Ba4Ca8 cuboctahedra; faces with four equivalent Ba(1)Ca12 cuboctahedra; and faces with sixteen Ca(1,1)Ba4Ca8 cuboctahedra. is represented by the CIF file [CIF]
data_BaCa3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.231
_cell_length_b   8.231
_cell_length_c   6.688
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   392.431
_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  0.333  0.667  0.750  1.0
  Ba  Ba1  1  0.667  0.333  0.250  1.0
  Ca  Ca2  1  0.161  0.323  0.250  1.0
  Ca  Ca3  1  0.677  0.839  0.250  1.0
  Ca  Ca4  1  0.161  0.839  0.250  1.0
  Ca  Ca5  1  0.839  0.677  0.750  1.0
  Ca  Ca6  1  0.323  0.161  0.750  1.0
  Ca  Ca7  1  0.839  0.161  0.750  1.0
[/CIF]
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