data_Si2Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.62
_cell_length_b   4.62
_cell_length_c   4.62
_cell_angle_alpha   106.18
_cell_angle_beta   106.18
_cell_angle_gamma   116.28
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2Ni
_chemical_formula_sum   'Si4 Ni2'
_cell_volume   75.15
_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
  Si  Si2  1  0.86  0.92  0.0  1.0
  Si  Si3  1  0.92  0.86  0.44  1.0
  Si  Si4  1  0.63  0.86  0.0  1.0
  Si  Si5  1  0.14  0.92  0.44  1.0
  Ni  Ni0  1  0.0  0.0  0.66  1.0
  Ni  Ni1  1  0.0  0.0  0.22  1.0

data_Si2Ni
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.62
_cell_length_b   4.62
_cell_length_c   4.62
_cell_angle_alpha   106.18
_cell_angle_beta   106.18
_cell_angle_gamma   116.28
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2Ni
_chemical_formula_sum   'Si4 Ni2'
_cell_volume   75.15
_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
  Si  Si0  1  0.14  0.08  -0.0  1.0
  Si  Si1  1  0.3  0.52  0.44  1.0
  Si  Si2  1  0.37  0.14  -0.0  1.0
  Si  Si3  1  0.52  0.58  0.44  1.0
  Ni  Ni4  1  0.22  0.22  0.22  1.0
  Ni  Ni5  1  0.66  0.66  0.66  1.0

Si Si Si Si Ni Ni
Si Si Si Si Ni Ni 0 2 o o o 0 5 + + o 1 3 + o o 1 4 + + o 