The compound described by Ac3Er is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ac sites. In the first Ac site, Ac(1) is bonded to four equivalent Ac(1), four equivalent Ac(2), and four equivalent Er(1) atoms to form AcAc8Er4 cuboctahedra that share corners with twelve equivalent Ac(1)Ac8Er4 cuboctahedra, edges with eight equivalent Ac(1)Ac8Er4 cuboctahedra, edges with eight equivalent Ac(2)Ac8Er4 cuboctahedra, edges with eight equivalent Er(1)Ac12 cuboctahedra, faces with four equivalent Ac(2)Ac8Er4 cuboctahedra, faces with four equivalent Er(1)Ac12 cuboctahedra, and faces with ten equivalent Ac(1)Ac8Er4 cuboctahedra. In the second Ac site, Ac(2) is bonded to eight equivalent Ac(1) and four equivalent Er(1) atoms to form AcAc8Er4 cuboctahedra that share corners with four equivalent Ac(2)Ac8Er4 cuboctahedra, corners with eight equivalent Er(1)Ac12 cuboctahedra, edges with eight equivalent Ac(2)Ac8Er4 cuboctahedra, edges with sixteen equivalent Ac(1)Ac8Er4 cuboctahedra, faces with four equivalent Ac(2)Ac8Er4 cuboctahedra, faces with six equivalent Er(1)Ac12 cuboctahedra, and faces with eight equivalent Ac(1)Ac8Er4 cuboctahedra. Er(1) is bonded to four equivalent Ac(2) and eight equivalent Ac(1) atoms to form ErAc12 cuboctahedra that share corners with four equivalent Er(1)Ac12 cuboctahedra, corners with eight equivalent Ac(2)Ac8Er4 cuboctahedra, edges with eight equivalent Er(1)Ac12 cuboctahedra, edges with sixteen equivalent Ac(1)Ac8Er4 cuboctahedra, faces with four equivalent Er(1)Ac12 cuboctahedra, faces with six equivalent Ac(2)Ac8Er4 cuboctahedra, and faces with eight equivalent Ac(1)Ac8Er4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ac3Er
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.716
_cell_length_b   6.716
_cell_length_c   6.716
_cell_angle_alpha   131.453
_cell_angle_beta   131.453
_cell_angle_gamma   71.095
_symmetry_Int_Tables_number   1
_cell_volume   166.637
_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  0.750  0.250  0.500  1.0
  Ac  Ac1  1  0.250  0.750  0.500  1.0
  Ac  Ac2  1  0.500  0.500  0.000  1.0
  Er  Er3  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by Ac3Er is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ac sites. In the first Ac site, Ac(1) is bonded to four equivalent Ac(1), four equivalent Ac(2), and four equivalent Er(1) atoms to form AcAc8Er4 cuboctahedra that share corners with twelve equivalent Ac(1)Ac8Er4 cuboctahedra, edges with eight equivalent Ac(1)Ac8Er4 cuboctahedra, edges with eight equivalent Ac(2)Ac8Er4 cuboctahedra, edges with eight equivalent Er(1)Ac12 cuboctahedra, faces with four equivalent Ac(2)Ac8Er4 cuboctahedra, faces with four equivalent Er(1)Ac12 cuboctahedra, and faces with ten equivalent Ac(1)Ac8Er4 cuboctahedra. In the second Ac site, Ac(2) is bonded to eight equivalent Ac(1) and four equivalent Er(1) atoms to form AcAc8Er4 cuboctahedra that share corners with four equivalent Ac(2)Ac8Er4 cuboctahedra, corners with eight equivalent Er(1)Ac12 cuboctahedra, edges with eight equivalent Ac(2)Ac8Er4 cuboctahedra, edges with sixteen equivalent Ac(1)Ac8Er4 cuboctahedra, faces with four equivalent Ac(2)Ac8Er4 cuboctahedra, faces with six equivalent Er(1)Ac12 cuboctahedra, and faces with eight equivalent Ac(1)Ac8Er4 cuboctahedra. Er(1) is bonded to four equivalent Ac(2) and eight equivalent Ac(1) atoms to form ErAc12 cuboctahedra that share corners with four equivalent Er(1)Ac12 cuboctahedra, corners with eight equivalent Ac(2)Ac8Er4 cuboctahedra, edges with eight equivalent Er(1)Ac12 cuboctahedra, edges with sixteen equivalent Ac(1)Ac8Er4 cuboctahedra, faces with four equivalent Er(1)Ac12 cuboctahedra, faces with six equivalent Ac(2)Ac8Er4 cuboctahedra, and faces with eight equivalent Ac(1)Ac8Er4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ac3Er
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.716
_cell_length_b   6.716
_cell_length_c   6.716
_cell_angle_alpha   131.453
_cell_angle_beta   131.453
_cell_angle_gamma   71.095
_symmetry_Int_Tables_number   1
_cell_volume   166.637
_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  0.750  0.250  0.500  1.0
  Ac  Ac1  1  0.250  0.750  0.500  1.0
  Ac  Ac2  1  0.500  0.500  0.000  1.0
  Er  Er3  1  0.000  0.000  0.000  1.0
[/CIF]
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