data_Mg2FeAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.47
_cell_length_b   5.47
_cell_length_c   5.47
_cell_angle_alpha   146.26
_cell_angle_beta   130.84
_cell_angle_gamma   60.95
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2FeAs
_chemical_formula_sum   'Mg2 Fe1 As1'
_cell_volume   68.17
_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  0.0  0.28  0.44  1.0
  Mg  Mg3  1  0.0  0.0  0.47  1.0
  Fe  Fe1  1  0.0  0.0  0.8  1.0
  As  As0  1  0.0  0.28  0.43  1.0

data_Mg2FeAs
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.18
_cell_length_b   4.55
_cell_length_c   5.47
_cell_angle_alpha   114.58
_cell_angle_beta   106.87
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2FeAs
_chemical_formula_sum   'Mg2 Fe1 As1'
_cell_volume   68.17
_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  Mg0  1  0.0  0.47  0.47  1.0
  Mg  Mg1  1  0.72  0.17  0.17  1.0
  Fe  Fe2  1  0.0  0.8  0.8  1.0
  As  As3  1  0.72  0.15  0.15  1.0

Mg Mg Fe As
Mg Mg Fe As 0 3 o o o 0 1 o o o 1 3 o o o 1 2 o o o 