data_Cs2AcHf
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.37
_cell_length_b   6.37
_cell_length_c   6.37
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Cs2AcHf
_chemical_formula_sum   'Cs2 Ac1 Hf1'
_cell_volume   182.69
_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
  Cs  Cs1  1  0.76  0.76  0.76  1.0
  Cs  Cs2  1  0.25  0.25  0.25  1.0
  Ac  Ac0  1  0.5  0.5  0.5  1.0
  Hf  Hf3  1  0.0  0.0  0.0  1.0

data_Cs2AcHf
_symmetry_space_group_name_H-M   R3m
_cell_length_a   6.37
_cell_length_b   6.37
_cell_length_c   15.6
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Cs2AcHf
_chemical_formula_sum   'Cs6 Ac3 Hf3'
_cell_volume   548.06
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Cs  Cs0  3  0.0  0.0  0.24  1.0
  Cs  Cs1  3  0.0  0.0  0.75  1.0
  Ac  Ac2  3  0.0  0.0  0.5  1.0
  Hf  Hf3  3  0.0  0.0  0.0  1.0

Cs Cs Ac Hf
Cs Cs Ac Hf 0 3 + o + 0 3 o + + 0 3 + + o 0 3 + + + 0 1 o o + 0 1 o + o 0 1 o + + 0 1 + o o 0 1 + o + 0 1 + + o 0 2 o o o 0 2 o o + 0 2 o + o 0 2 + o o 1 3 o o o 1 3 o o + 1 3 o + o 1 3 + o o 1 2 - o o 1 2 o - o 1 2 o o - 1 2 o o o 2 3 o o + 2 3 o + o 2 3 o + + 2 3 + o o 2 3 + o + 2 3 + + o 
Cs2AcHf is Heusler structured and crystallizes in the trigonal R3m space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a body-centered cubic geometry to four equivalent Ac(1) and four equivalent Hf(1) atoms. There are three shorter (3.89 Å) and one longer (3.93 Å) Cs(1)-Ac(1) bond length. There is one shorter (3.82 Å) and three longer (3.93 Å) Cs(1)-Hf(1) bond lengths. In the second Cs site, Cs(2) is bonded in a body-centered cubic geometry to four equivalent Ac(1) and four equivalent Hf(1) atoms. There are three shorter (3.89 Å) and one longer (3.93 Å) Cs(2)-Ac(1) bond length. There are three shorter (3.89 Å) and one longer (3.93 Å) Cs(2)-Hf(1) bond length. Ac(1) is bonded in a body-centered cubic geometry to four equivalent Cs(1) and four equivalent Cs(2) atoms. Hf(1) is bonded in a body-centered cubic geometry to four equivalent Cs(1) and four equivalent Cs(2) atoms.