data_ErN
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.47
_cell_length_b   3.47
_cell_length_c   3.47
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ErN
_chemical_formula_sum   'Er1 N1'
_cell_volume   29.58
_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
  Er  Er1  1  0.45  0.45  0.45  1.0
  N  N0  1  0.0  0.0  0.0  1.0

data_ErN
_symmetry_space_group_name_H-M   R3m
_cell_length_a   3.47
_cell_length_b   3.47
_cell_length_c   8.5
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   ErN
_chemical_formula_sum   'Er3 N3'
_cell_volume   88.73
_cell_formula_units_Z   3
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  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+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
  Er  Er0  3  0.0  0.0  0.55  1.0
  N  N1  3  0.0  0.0  0.0  1.0

Er N
Er N 0 1 o o + 0 1 o + o 0 1 o + + 0 1 + o o 0 1 + o + 0 1 + + o 
ErN is Halite, Rock Salt structured and crystallizes in the trigonal R3m space group. Er(1) is bonded to six equivalent N(1) atoms to form a mixture of distorted corner and edge-sharing ErN6 octahedra. The corner-sharing octahedral tilt angles are 15°. There are three shorter (2.25 Å) and three longer (2.70 Å) Er(1)-N(1) bond lengths. N(1) is bonded to six equivalent Er(1) atoms to form a mixture of distorted corner and edge-sharing NEr6 octahedra. The corner-sharing octahedral tilt angles are 15°.