data_Mg2FeAg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.98
_cell_length_b   2.98
_cell_length_c   8.03
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2FeAg
_chemical_formula_sum   'Mg2 Fe1 Ag1'
_cell_volume   71.36
_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
  Mg  Mg2  1  0.49  0.49  0.75  1.0
  Mg  Mg3  1  0.0  0.0  0.19  1.0
  Fe  Fe1  1  0.0  0.0  0.96  1.0
  Ag  Ag0  1  0.49  0.49  0.16  1.0

data_Mg2FeAg
_symmetry_space_group_name_H-M   P4mm
_cell_length_a   2.98
_cell_length_b   2.98
_cell_length_c   8.03
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   99
_chemical_formula_structural   Mg2FeAg
_chemical_formula_sum   'Mg2 Fe1 Ag1'
_cell_volume   71.36
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x, z'
  3  '-x, -y, z'
  4  'y, -x, z'
  5  '-x, y, z'
  6  'y, x, z'
  7  'x, -y, z'
  8  '-y, -x, 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
  Mg  Mg0  1  0.0  0.0  0.19  1.0
  Mg  Mg1  1  0.5  0.5  0.75  1.0
  Fe  Fe2  1  0.0  0.0  0.96  1.0
  Ag  Ag3  1  0.5  0.5  0.16  1.0

Mg Mg Fe Ag
Mg Mg Fe Ag 0 2 o o o 0 2 o + o 0 2 + o o 0 2 + + o 0 0 + o o 0 0 o + o 1 3 - - o 1 3 - o o 1 3 o - o 1 3 o o o 1 2 o o - 