The material structure described by Ba3Ac is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Ba(1) is bonded to eight equivalent Ba(1) and four equivalent Ac(1) atoms to form distorted BaBa8Ac4 cuboctahedra that share corners with four equivalent Ac(1)Ba12 cuboctahedra, corners with fourteen equivalent Ba(1)Ba8Ac4 cuboctahedra, edges with six equivalent Ac(1)Ba12 cuboctahedra, edges with twelve equivalent Ba(1)Ba8Ac4 cuboctahedra, faces with four equivalent Ac(1)Ba12 cuboctahedra, and faces with sixteen equivalent Ba(1)Ba8Ac4 cuboctahedra. Ac(1) is bonded to twelve equivalent Ba(1) atoms to form AcBa12 cuboctahedra that share corners with six equivalent Ac(1)Ba12 cuboctahedra, corners with twelve equivalent Ba(1)Ba8Ac4 cuboctahedra, edges with eighteen equivalent Ba(1)Ba8Ac4 cuboctahedra, faces with eight equivalent Ac(1)Ba12 cuboctahedra, and faces with twelve equivalent Ba(1)Ba8Ac4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3Ac
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.728
_cell_length_b   8.728
_cell_length_c   6.936
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   457.602
_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  0.171  0.341  0.250  1.0
  Ba  Ba1  1  0.659  0.829  0.250  1.0
  Ba  Ba2  1  0.171  0.829  0.250  1.0
  Ba  Ba3  1  0.829  0.659  0.750  1.0
  Ba  Ba4  1  0.341  0.171  0.750  1.0
  Ba  Ba5  1  0.829  0.171  0.750  1.0
  Ac  Ac6  1  0.333  0.667  0.750  1.0
  Ac  Ac7  1  0.667  0.333  0.250  1.0
[/CIF]
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The material structure described by Ba3Ac is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Ba(1) is bonded to eight equivalent Ba(1) and four equivalent Ac(1) atoms to form distorted BaBa8Ac4 cuboctahedra that share corners with four equivalent Ac(1)Ba12 cuboctahedra, corners with fourteen equivalent Ba(1)Ba8Ac4 cuboctahedra, edges with six equivalent Ac(1)Ba12 cuboctahedra, edges with twelve equivalent Ba(1)Ba8Ac4 cuboctahedra, faces with four equivalent Ac(1)Ba12 cuboctahedra, and faces with sixteen equivalent Ba(1)Ba8Ac4 cuboctahedra. Ac(1) is bonded to twelve equivalent Ba(1) atoms to form AcBa12 cuboctahedra that share corners with six equivalent Ac(1)Ba12 cuboctahedra, corners with twelve equivalent Ba(1)Ba8Ac4 cuboctahedra, edges with eighteen equivalent Ba(1)Ba8Ac4 cuboctahedra, faces with eight equivalent Ac(1)Ba12 cuboctahedra, and faces with twelve equivalent Ba(1)Ba8Ac4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3Ac
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.728
_cell_length_b   8.728
_cell_length_c   6.936
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   457.602
_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  0.171  0.341  0.250  1.0
  Ba  Ba1  1  0.659  0.829  0.250  1.0
  Ba  Ba2  1  0.171  0.829  0.250  1.0
  Ba  Ba3  1  0.829  0.659  0.750  1.0
  Ba  Ba4  1  0.341  0.171  0.750  1.0
  Ba  Ba5  1  0.829  0.171  0.750  1.0
  Ac  Ac6  1  0.333  0.667  0.750  1.0
  Ac  Ac7  1  0.667  0.333  0.250  1.0
[/CIF]
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