data_AcNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.98
_cell_length_b   3.69
_cell_length_c   5.39
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   AcNi
_chemical_formula_sum   'Ac2 Ni2'
_cell_volume   98.97
_cell_formula_units_Z   2
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  0.73  0.84  0.31  1.0
  Ac  Ac1  1  0.24  0.84  0.08  1.0
  Ni  Ni2  1  0.24  0.0  0.62  1.0
  Ni  Ni3  1  0.73  0.0  0.77  1.0

data_AcNi
_symmetry_space_group_name_H-M   P2
_cell_length_a   4.98
_cell_length_b   3.69
_cell_length_c   5.39
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   3
_chemical_formula_structural   AcNi
_chemical_formula_sum   'Ac2 Ni2'
_cell_volume   98.97
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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  2  0.24  0.84  0.12  1.0
  Ni  Ni1  2  0.24  0.0  0.58  1.0

Ac Ac Ni Ni
Ac Ac Ni Ni 0 1 o o o 0 1 + o o 0 2 o + o 0 2 + + o 0 3 o + - 0 3 o + o 1 3 - + - 1 3 o + - 1 2 o + - 1 2 o + o 2 3 - o o 2 3 o o o 