The crystal structure described by Ba3Ac is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent Ba(1), four equivalent Ba(2), and four equivalent Ac(1) atoms to form BaBa8Ac4 cuboctahedra that share corners with twelve equivalent Ba(1)Ba8Ac4 cuboctahedra, edges with eight equivalent Ba(1)Ba8Ac4 cuboctahedra, edges with eight equivalent Ba(2)Ba8Ac4 cuboctahedra, edges with eight equivalent Ac(1)Ba12 cuboctahedra, faces with four equivalent Ba(2)Ba8Ac4 cuboctahedra, faces with four equivalent Ac(1)Ba12 cuboctahedra, and faces with ten equivalent Ba(1)Ba8Ac4 cuboctahedra. In the second Ba site, Ba(2) is bonded to eight equivalent Ba(1) and four equivalent Ac(1) atoms to form BaBa8Ac4 cuboctahedra that share corners with four equivalent Ba(2)Ba8Ac4 cuboctahedra, corners with eight equivalent Ac(1)Ba12 cuboctahedra, edges with eight equivalent Ba(2)Ba8Ac4 cuboctahedra, edges with sixteen equivalent Ba(1)Ba8Ac4 cuboctahedra, faces with four equivalent Ba(2)Ba8Ac4 cuboctahedra, faces with six equivalent Ac(1)Ba12 cuboctahedra, and faces with eight equivalent Ba(1)Ba8Ac4 cuboctahedra. Ac(1) is bonded to four equivalent Ba(2) and eight equivalent Ba(1) atoms to form AcBa12 cuboctahedra that share corners with four equivalent Ac(1)Ba12 cuboctahedra, corners with eight equivalent Ba(2)Ba8Ac4 cuboctahedra, edges with eight equivalent Ac(1)Ba12 cuboctahedra, edges with sixteen equivalent Ba(1)Ba8Ac4 cuboctahedra, faces with four equivalent Ac(1)Ba12 cuboctahedra, faces with six equivalent Ba(2)Ba8Ac4 cuboctahedra, and faces with eight equivalent Ba(1)Ba8Ac4 cuboctahedra. is represented by the CIF file [CIF]
data_Ba3Ac
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.541
_cell_length_b   7.541
_cell_length_c   7.541
_cell_angle_alpha   132.525
_cell_angle_beta   132.525
_cell_angle_gamma   69.402
_symmetry_Int_Tables_number   1
_cell_volume   228.482
_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  0.750  0.250  0.500  1.0
  Ba  Ba1  1  0.250  0.750  0.500  1.0
  Ba  Ba2  1  0.500  0.500  0.000  1.0
  Ac  Ac3  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Ba3Ac is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent Ba(1), four equivalent Ba(2), and four equivalent Ac(1) atoms to form BaBa8Ac4 cuboctahedra that share corners with twelve equivalent Ba(1)Ba8Ac4 cuboctahedra, edges with eight equivalent Ba(1)Ba8Ac4 cuboctahedra, edges with eight equivalent Ba(2)Ba8Ac4 cuboctahedra, edges with eight equivalent Ac(1)Ba12 cuboctahedra, faces with four equivalent Ba(2)Ba8Ac4 cuboctahedra, faces with four equivalent Ac(1)Ba12 cuboctahedra, and faces with ten equivalent Ba(1)Ba8Ac4 cuboctahedra. In the second Ba site, Ba(2) is bonded to eight equivalent Ba(1) and four equivalent Ac(1) atoms to form BaBa8Ac4 cuboctahedra that share corners with four equivalent Ba(2)Ba8Ac4 cuboctahedra, corners with eight equivalent Ac(1)Ba12 cuboctahedra, edges with eight equivalent Ba(2)Ba8Ac4 cuboctahedra, edges with sixteen equivalent Ba(1)Ba8Ac4 cuboctahedra, faces with four equivalent Ba(2)Ba8Ac4 cuboctahedra, faces with six equivalent Ac(1)Ba12 cuboctahedra, and faces with eight equivalent Ba(1)Ba8Ac4 cuboctahedra. Ac(1) is bonded to four equivalent Ba(2) and eight equivalent Ba(1) atoms to form AcBa12 cuboctahedra that share corners with four equivalent Ac(1)Ba12 cuboctahedra, corners with eight equivalent Ba(2)Ba8Ac4 cuboctahedra, edges with eight equivalent Ac(1)Ba12 cuboctahedra, edges with sixteen equivalent Ba(1)Ba8Ac4 cuboctahedra, faces with four equivalent Ac(1)Ba12 cuboctahedra, faces with six equivalent Ba(2)Ba8Ac4 cuboctahedra, and faces with eight equivalent Ba(1)Ba8Ac4 cuboctahedra. is represented by the CIF file [CIF]
data_Ba3Ac
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.541
_cell_length_b   7.541
_cell_length_c   7.541
_cell_angle_alpha   132.525
_cell_angle_beta   132.525
_cell_angle_gamma   69.402
_symmetry_Int_Tables_number   1
_cell_volume   228.482
_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  0.750  0.250  0.500  1.0
  Ba  Ba1  1  0.250  0.750  0.500  1.0
  Ba  Ba2  1  0.500  0.500  0.000  1.0
  Ac  Ac3  1  0.000  0.000  0.000  1.0
[/CIF]
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