data_Li2AsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.92
_cell_length_b   4.92
_cell_length_c   2.94
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   105.84
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Li2AsSe
_chemical_formula_sum   'Li2 As1 Se1'
_cell_volume   68.48
_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  Li1  1  0.48  0.96  0.47  1.0
  Li  Li2  1  0.48  0.04  0.47  1.0
  As  As0  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.96  0.0  0.0  1.0

data_Li2AsSe
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.94
_cell_length_b   4.92
_cell_length_c   4.92
_cell_angle_alpha   105.84
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Li2AsSe
_chemical_formula_sum   'Li2 As1 Se1'
_cell_volume   68.48
_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  Li0  1  0.47  0.48  0.04  1.0
  Li  Li1  1  0.47  0.48  0.96  1.0
  As  As2  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.0  0.96  0.0  1.0

Li Li As Se
Li Li As Se 0 1 o + o 2 3 - o o 
(Li)2AsSe crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one arsenic;selenium molecule and one lithium molecule.