data_Si4Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.51
_cell_length_b   4.51
_cell_length_c   4.51
_cell_angle_alpha   102.3
_cell_angle_beta   102.3
_cell_angle_gamma   125.02
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si4Ni
_chemical_formula_sum   'Si4 Ni1'
_cell_volume   66.6
_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
  Si  Si1  1  0.18  0.13  0.0  1.0
  Si  Si2  1  0.13  0.48  0.0  1.0
  Si  Si3  1  0.65  0.69  0.08  1.0
  Si  Si4  1  0.69  0.35  0.08  1.0
  Ni  Ni0  1  0.0  0.0  0.0  1.0

data_Si4Ni
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.16
_cell_length_b   4.51
_cell_length_c   4.51
_cell_angle_alpha   77.7
_cell_angle_beta   62.51
_cell_angle_gamma   62.51
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si4Ni
_chemical_formula_sum   'Si4 Ni1'
_cell_volume   66.6
_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
  Si  Si0  1  0.13  0.05  -0.0  1.0
  Si  Si1  1  0.35  0.34  0.92  1.0
  Si  Si2  1  0.48  0.66  -0.0  1.0
  Si  Si3  1  0.69  0.95  0.92  1.0
  Ni  Ni4  1  0.0  0.0  0.0  1.0

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