data_Si2NiMo
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.77
_cell_length_b   4.77
_cell_length_c   2.69
_cell_angle_alpha   102.39
_cell_angle_beta   102.39
_cell_angle_gamma   110.04
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2NiMo
_chemical_formula_sum   'Si2 Ni1 Mo1'
_cell_volume   53.38
_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  Si2  1  0.86  0.95  0.25  1.0
  Si  Si3  1  0.86  0.05  0.25  1.0
  Ni  Ni1  1  0.0  0.0  0.0  1.0
  Mo  Mo0  1  0.73  0.0  0.0  1.0

data_Si2NiMo
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.69
_cell_length_b   4.77
_cell_length_c   4.77
_cell_angle_alpha   110.04
_cell_angle_beta   102.39
_cell_angle_gamma   102.39
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2NiMo
_chemical_formula_sum   'Si2 Ni1 Mo1'
_cell_volume   53.38
_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  0.25  0.86  0.05  1.0
  Si  Si1  1  0.25  0.86  0.95  1.0
  Ni  Ni2  1  0.0  0.0  0.0  1.0
  Mo  Mo3  1  0.0  0.73  0.0  1.0

Si Si Ni Mo
Si Si Ni Mo 0 1 o + o 0 2 + + o 1 2 + o o 1 3 o o o 