data_SiNiAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.23
_cell_length_b   6.23
_cell_length_c   6.23
_cell_angle_alpha   33.28
_cell_angle_beta   33.28
_cell_angle_gamma   33.28
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiNiAs2
_chemical_formula_sum   'Si1 Ni1 As2'
_cell_volume   64.71
_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  Si3  1  0.0  0.0  0.0  1.0
  Ni  Ni2  1  0.0  0.0  0.81  1.0
  As  As0  1  0.0  0.0  0.29  1.0
  As  As1  1  0.0  0.0  0.34  1.0

data_SiNiAs2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.18
_cell_length_b   3.57
_cell_length_c   6.23
_cell_angle_alpha   90.0
_cell_angle_beta   109.31
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   SiNiAs2
_chemical_formula_sum   'Si2 Ni2 As4'
_cell_volume   129.41
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.0  0.0  0.0  1.0
  Ni  Ni1  2  -0.0  0.0  0.19  1.0
  As  As2  2  -0.0  0.0  0.66  1.0
  As  As3  2  -0.0  0.0  0.71  1.0

Si Ni As As
Si Ni As As 0 1 o o - 2 3 o o o 