data_KEr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.04
_cell_length_b   7.04
_cell_length_c   7.04
_cell_angle_alpha   30.17
_cell_angle_beta   30.17
_cell_angle_gamma   30.17
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KEr
_chemical_formula_sum   'K1 Er1'
_cell_volume   78.23
_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
  K  K1  1  0.0  0.0  0.0  1.0
  Er  Er0  1  0.0  0.0  0.08  1.0

data_KEr
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.35
_cell_length_b   3.67
_cell_length_c   7.04
_cell_angle_alpha   90.0
_cell_angle_beta   107.49
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   KEr
_chemical_formula_sum   'K2 Er2'
_cell_volume   156.47
_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
  K  K0  2  0.0  0.0  0.0  1.0
  Er  Er1  2  0.0  0.0  0.92  1.0

K Er
K Er 0 1 o o o 