data_NaErF4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.59
_cell_length_b   6.59
_cell_length_c   6.59
_cell_angle_alpha   131.09
_cell_angle_beta   131.09
_cell_angle_gamma   71.67
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaErF4
_chemical_formula_sum   'Na2 Er2 F8'
_cell_volume   158.92
_cell_formula_units_Z   2
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
  Na  Na0  1  0.0  0.0  0.0  1.0
  Na  Na1  1  0.0  0.73  0.67  1.0
  Er  Er2  1  0.0  0.0  0.34  1.0
  Er  Er3  1  0.73  0.0  0.67  1.0
  F  F4  1  0.48  0.36  0.34  1.0
  F  F5  1  0.24  0.36  0.68  1.0
  F  F6  1  0.36  0.48  0.66  1.0
  F  F7  1  0.36  0.97  0.66  1.0
  F  F8  1  0.76  0.36  0.68  1.0
  F  F9  1  0.36  0.24  0.01  1.0
  F  F10  1  0.36  0.76  0.01  1.0
  F  F11  1  0.97  0.36  0.34  1.0

data_NaErF4
_symmetry_space_group_name_H-M   P1
_cell_length_a   5.45
_cell_length_b   5.45
_cell_length_c   6.59
_cell_angle_alpha   114.45
_cell_angle_beta   114.45
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaErF4
_chemical_formula_sum   'Na2 Er2 F8'
_cell_volume   158.92
_cell_formula_units_Z   2
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
  Na  Na0  1  0.0  0.0  0.0  1.0
  Na  Na1  1  0.94  0.67  0.94  1.0
  Er  Er2  1  0.34  0.34  0.34  1.0
  Er  Er3  1  0.67  0.94  0.94  1.0
  F  F4  1  0.18  0.3  0.82  1.0
  F  F5  1  0.25  0.64  0.89  1.0
  F  F6  1  0.31  0.43  0.07  1.0
  F  F7  1  0.31  0.92  0.56  1.0
  F  F8  1  0.69  0.3  0.33  1.0
  F  F9  1  0.76  0.64  0.4  1.0
  F  F10  1  0.97  0.85  0.49  1.0
  F  F11  1  0.97  0.36  1.0  1.0

Na Na Er Er F F F F F F F F
Na Na Er Er F F F F F F F F 0 3 - o - 0 11 - o o 0 1 o - - 0 2 o o o 1 3 - + o 1 11 - o o 1 10 o o + 2 11 - o o 2 7 o - o 2 5 o o o 4 9 o o o 4 8 o o o 5 6 o o o 5 10 o o + 5 11 - o o 6 10 o o + 6 11 - o o 7 9 o + + 
NaErF4 crystallizes in the triclinic P1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 2-coordinate geometry to one Er(2) and one F(8) atom. The Na(1)-Er(2) bond length is 1.68 Å. The Na(1)-F(8) bond length is 1.99 Å. In the second Na site, Na(2) is bonded in a distorted L-shaped geometry to one Er(2), one F(7), and one F(8) atom. The Na(2)-Er(2) bond length is 2.10 Å. The Na(2)-F(7) bond length is 1.85 Å. The Na(2)-F(8) bond length is 1.85 Å. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 2-coordinate geometry to one F(2), one F(4), and one F(6) atom. The Er(1)-F(2) bond length is 2.00 Å. The Er(1)-F(4) bond length is 1.96 Å. The Er(1)-F(6) bond length is 2.62 Å. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one F(4), one F(5), one F(7), and one F(8) atom. The Er(2)-F(4) bond length is 2.43 Å. The Er(2)-F(5) bond length is 2.43 Å. The Er(2)-F(7) bond length is 2.62 Å. The Er(2)-F(8) bond length is 2.62 Å. There are eight inequivalent F sites. In the first F site, F(1) is bonded in a distorted bent 150 degrees geometry to one F(5) and one F(6) atom. The F(1)-F(5) bond length is 1.72 Å. The F(1)-F(6) bond length is 1.36 Å. In the second F site, F(2) is bonded in a 1-coordinate geometry to one Er(1) and one F(3) atom. The F(2)-F(3) bond length is 1.33 Å. In the third F site, F(3) is bonded in a 1-coordinate geometry to one F(2) atom. In the fourth F site, F(4) is bonded in a distorted bent 120 degrees geometry to one Er(1), one Er(2), and one F(6) atom. The F(4)-F(6) bond length is 1.72 Å. In the fifth F site, F(5) is bonded in a 1-coordinate geometry to one Er(2) and one F(1) atom. In the sixth F site, F(6) is bonded in a 3-coordinate geometry to one Er(1), one F(1), and one F(4) atom. In the seventh F site, F(7) is bonded in a 1-coordinate geometry to one Na(2) and one Er(2) atom. In the eighth F site, F(8) is bonded in a distorted linear geometry to one Na(1), one Na(2), and one Er(2) atom.