The crystal structure described by AcY3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Ac(1) is bonded to four equivalent Y(2) and eight equivalent Y(1) atoms to form AcY12 cuboctahedra that share corners with four equivalent Ac(1)Y12 cuboctahedra, corners with eight equivalent Y(2)Ac4Y8 cuboctahedra, edges with eight equivalent Ac(1)Y12 cuboctahedra, edges with sixteen equivalent Y(1)Ac4Y8 cuboctahedra, faces with four equivalent Ac(1)Y12 cuboctahedra, faces with six equivalent Y(2)Ac4Y8 cuboctahedra, and faces with eight equivalent Y(1)Ac4Y8 cuboctahedra. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to four equivalent Ac(1), four equivalent Y(1), and four equivalent Y(2) atoms to form YAc4Y8 cuboctahedra that share corners with twelve equivalent Y(1)Ac4Y8 cuboctahedra, edges with eight equivalent Ac(1)Y12 cuboctahedra, edges with eight equivalent Y(1)Ac4Y8 cuboctahedra, edges with eight equivalent Y(2)Ac4Y8 cuboctahedra, faces with four equivalent Ac(1)Y12 cuboctahedra, faces with four equivalent Y(2)Ac4Y8 cuboctahedra, and faces with ten equivalent Y(1)Ac4Y8 cuboctahedra. In the second Y site, Y(2) is bonded to four equivalent Ac(1) and eight equivalent Y(1) atoms to form YAc4Y8 cuboctahedra that share corners with four equivalent Y(2)Ac4Y8 cuboctahedra, corners with eight equivalent Ac(1)Y12 cuboctahedra, edges with eight equivalent Y(2)Ac4Y8 cuboctahedra, edges with sixteen equivalent Y(1)Ac4Y8 cuboctahedra, faces with four equivalent Y(2)Ac4Y8 cuboctahedra, faces with six equivalent Ac(1)Y12 cuboctahedra, and faces with eight equivalent Y(1)Ac4Y8 cuboctahedra. is represented by the CIF card [CIF]
data_AcY3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.356
_cell_length_b   6.356
_cell_length_c   6.356
_cell_angle_alpha   130.684
_cell_angle_beta   130.684
_cell_angle_gamma   72.315
_symmetry_Int_Tables_number   1
_cell_volume   144.345
_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
  Ac  Ac0  1  0.000  0.000  0.000  1.0
  Y  Y1  1  0.750  0.250  0.500  1.0
  Y  Y2  1  0.250  0.750  0.500  1.0
  Y  Y3  1  0.500  0.500  0.000  1.0
[/CIF]
.
The crystal structure described by AcY3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Ac(1) is bonded to four equivalent Y(2) and eight equivalent Y(1) atoms to form AcY12 cuboctahedra that share corners with four equivalent Ac(1)Y12 cuboctahedra, corners with eight equivalent Y(2)Ac4Y8 cuboctahedra, edges with eight equivalent Ac(1)Y12 cuboctahedra, edges with sixteen equivalent Y(1)Ac4Y8 cuboctahedra, faces with four equivalent Ac(1)Y12 cuboctahedra, faces with six equivalent Y(2)Ac4Y8 cuboctahedra, and faces with eight equivalent Y(1)Ac4Y8 cuboctahedra. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to four equivalent Ac(1), four equivalent Y(1), and four equivalent Y(2) atoms to form YAc4Y8 cuboctahedra that share corners with twelve equivalent Y(1)Ac4Y8 cuboctahedra, edges with eight equivalent Ac(1)Y12 cuboctahedra, edges with eight equivalent Y(1)Ac4Y8 cuboctahedra, edges with eight equivalent Y(2)Ac4Y8 cuboctahedra, faces with four equivalent Ac(1)Y12 cuboctahedra, faces with four equivalent Y(2)Ac4Y8 cuboctahedra, and faces with ten equivalent Y(1)Ac4Y8 cuboctahedra. In the second Y site, Y(2) is bonded to four equivalent Ac(1) and eight equivalent Y(1) atoms to form YAc4Y8 cuboctahedra that share corners with four equivalent Y(2)Ac4Y8 cuboctahedra, corners with eight equivalent Ac(1)Y12 cuboctahedra, edges with eight equivalent Y(2)Ac4Y8 cuboctahedra, edges with sixteen equivalent Y(1)Ac4Y8 cuboctahedra, faces with four equivalent Y(2)Ac4Y8 cuboctahedra, faces with six equivalent Ac(1)Y12 cuboctahedra, and faces with eight equivalent Y(1)Ac4Y8 cuboctahedra. is represented by the CIF card [CIF]
data_AcY3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.356
_cell_length_b   6.356
_cell_length_c   6.356
_cell_angle_alpha   130.684
_cell_angle_beta   130.684
_cell_angle_gamma   72.315
_symmetry_Int_Tables_number   1
_cell_volume   144.345
_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
  Ac  Ac0  1  0.000  0.000  0.000  1.0
  Y  Y1  1  0.750  0.250  0.500  1.0
  Y  Y2  1  0.250  0.750  0.500  1.0
  Y  Y3  1  0.500  0.500  0.000  1.0
[/CIF]
.