The material described by Ac is alpha Samarium structured and crystallizes in the trigonal R-3m space group. There are three inequivalent Ac sites. In the first Ac site, Ac(1) is bonded to six equivalent Ac(1) and six equivalent Ac(2) atoms to form a mixture of corner, face, and edge-sharing AcAc12 cuboctahedra. In the second Ac site, Ac(2) is bonded to three equivalent Ac(1) and nine equivalent Ac(2) atoms to form a mixture of corner, face, and edge-sharing AcAc12 cuboctahedra. In the third Ac site, Ac(2) is bonded to three equivalent Ac(1) and nine Ac(2,2) atoms to form a mixture of corner, face, and edge-sharing AcAc12 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ac
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.047
_cell_length_b   4.047
_cell_length_c   10.064
_cell_angle_alpha   78.402
_cell_angle_beta   101.598
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   138.841
_cell_formula_units_Z   3
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
  Ac  Ac1  1  0.777  0.223  0.332  1.0
  Ac  Ac2  1  0.223  0.777  0.668  1.0
[/CIF]
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The material described by Ac is alpha Samarium structured and crystallizes in the trigonal R-3m space group. There are three inequivalent Ac sites. In the first Ac site, Ac(1) is bonded to six equivalent Ac(1) and six equivalent Ac(2) atoms to form a mixture of corner, face, and edge-sharing AcAc12 cuboctahedra. In the second Ac site, Ac(2) is bonded to three equivalent Ac(1) and nine equivalent Ac(2) atoms to form a mixture of corner, face, and edge-sharing AcAc12 cuboctahedra. In the third Ac site, Ac(2) is bonded to three equivalent Ac(1) and nine Ac(2,2) atoms to form a mixture of corner, face, and edge-sharing AcAc12 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ac
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.047
_cell_length_b   4.047
_cell_length_c   10.064
_cell_angle_alpha   78.402
_cell_angle_beta   101.598
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   138.841
_cell_formula_units_Z   3
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
  Ac  Ac1  1  0.777  0.223  0.332  1.0
  Ac  Ac2  1  0.223  0.777  0.668  1.0
[/CIF]
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