data_MgH2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.73
_cell_length_b   4.73
_cell_length_c   4.73
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgH2
_chemical_formula_sum   'Mg4 H8'
_cell_volume   105.92
_cell_formula_units_Z   4
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  Mg8  1  0.0  0.0  0.0  1.0
  Mg  Mg9  1  0.37  0.0  0.37  1.0
  Mg  Mg10  1  0.37  0.37  0.0  1.0
  Mg  Mg11  1  0.0  0.37  0.37  1.0
  H  H0  1  0.64  0.64  0.64  1.0
  H  H1  1  0.72  0.09  0.01  1.0
  H  H2  1  0.01  0.72  0.09  1.0
  H  H3  1  0.09  0.01  0.72  1.0
  H  H4  1  0.09  0.09  0.09  1.0
  H  H5  1  0.01  0.64  0.72  1.0
  H  H6  1  0.72  0.01  0.64  1.0
  H  H7  1  0.64  0.72  0.01  1.0

data_MgH2
_symmetry_space_group_name_H-M   R3
_cell_length_a   6.69
_cell_length_b   6.69
_cell_length_c   8.2
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   146
_chemical_formula_structural   MgH2
_chemical_formula_sum   'Mg12 H24'
_cell_volume   317.76
_cell_formula_units_Z   12
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  'x+1/3, y+2/3, z+2/3'
  5  '-y+1/3, x-y+2/3, z+2/3'
  6  '-x+y+1/3, -x+2/3, z+2/3'
  7  'x+2/3, y+1/3, z+1/3'
  8  '-y+2/3, x-y+1/3, z+1/3'
  9  '-x+y+2/3, -x+1/3, z+1/3'
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  9  0.09  0.54  0.91  1.0
  Mg  Mg1  3  0.0  0.0  0.0  1.0
  H  H2  9  0.07  0.85  0.94  1.0
  H  H3  9  0.18  0.45  0.46  1.0
  H  H4  3  0.0  0.0  0.09  1.0
  H  H5  3  0.0  0.0  0.64  1.0

Mg Mg Mg Mg H H H H H H H H