data_LiCu4Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.95
_cell_length_b   4.95
_cell_length_c   4.95
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   LiCu4Se
_chemical_formula_sum   'Li1 Cu4 Se1'
_cell_volume   85.68
_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
  Li  Li4  1  0.0  0.0  0.0  1.0
  Cu  Cu0  1  0.62  0.62  0.38  1.0
  Cu  Cu1  1  0.62  0.38  0.62  1.0
  Cu  Cu2  1  0.38  0.62  0.62  1.0
  Cu  Cu3  1  0.38  0.38  0.38  1.0
  Se  Se5  1  0.75  0.75  0.75  1.0

data_LiCu4Se
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.95
_cell_length_b   4.95
_cell_length_c   12.12
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   LiCu4Se
_chemical_formula_sum   'Li3 Cu12 Se3'
_cell_volume   257.03
_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
  Li  Li0  3  0.0  0.0  0.0  1.0
  Cu  Cu1  9  0.16  0.08  0.46  1.0
  Cu  Cu2  3  0.0  0.0  0.62  1.0
  Se  Se3  3  0.0  0.0  0.25  1.0

Li Cu Cu Cu Cu Se
LiCu4Se crystallizes in the trigonal R3m space group. Li(1) is bonded in a 10-coordinate geometry to three equivalent Cu(1), three equivalent Cu(2), and four equivalent Se(1) atoms. All Li(1)-Cu(1) bond lengths are 2.68 Å. All Li(1)-Cu(2) bond lengths are 2.91 Å. There are three shorter (3.03 Å) and one longer (3.04 Å) Li(1)-Se(1) bond length. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 6-coordinate geometry to one Li(1), one Cu(2), two equivalent Cu(1), and two equivalent Se(1) atoms. The Cu(1)-Cu(2) bond length is 2.03 Å. Both Cu(1)-Cu(1) bond lengths are 1.17 Å. There is one shorter (2.64 Å) and one longer (2.65 Å) Cu(1)-Se(1) bond length. In the second Cu site, Cu(2) is bonded in a 9-coordinate geometry to three equivalent Li(1), three equivalent Cu(1), and three equivalent Se(1) atoms. All Cu(2)-Se(1) bond lengths are 2.89 Å. Se(1) is bonded in a 13-coordinate geometry to four equivalent Li(1), three equivalent Cu(2), and six equivalent Cu(1) atoms.