data_CsLi2As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.14
_cell_length_b   5.14
_cell_length_c   5.14
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CsLi2As
_chemical_formula_sum   'Cs1 Li2 As1'
_cell_volume   96.19
_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
  Cs  Cs1  1  0.64  0.64  0.64  1.0
  Li  Li2  1  0.45  0.45  0.45  1.0
  Li  Li3  1  0.82  0.82  0.82  1.0
  As  As0  1  0.0  0.0  0.0  1.0

data_CsLi2As
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.14
_cell_length_b   5.14
_cell_length_c   12.6
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CsLi2As
_chemical_formula_sum   'Cs3 Li6 As3'
_cell_volume   288.57
_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
  Cs  Cs0  3  0.0  0.0  0.36  1.0
  Li  Li1  3  0.0  0.0  0.18  1.0
  Li  Li2  3  0.0  0.0  0.55  1.0
  As  As3  3  0.0  0.0  0.0  1.0

Cs Li Li As
Cs Li Li As 0 1 o o o 0 2 o o o 2 3 + + + 
CsLi2As crystallizes in the trigonal R3m space group. Cs(1) is bonded to one Li(1), one Li(2), and three equivalent As(1) atoms to form CsLi2As3 trigonal bipyramids that share corners with six equivalent Cs(1)Li2As3 trigonal bipyramids and  a cornercorner with one As(1)Cs3Li trigonal pyramid. The Cs(1)-Li(1) bond length is 2.29 Å. The Cs(1)-Li(2) bond length is 2.29 Å. All Cs(1)-As(1) bond lengths are 2.99 Å. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a single-bond geometry to one Cs(1) atom. In the second Li site, Li(2) is bonded in a distorted linear geometry to one Cs(1) and one As(1) atom. The Li(2)-As(1) bond length is 2.29 Å. As(1) is bonded to three equivalent Cs(1) and one Li(2) atom to form distorted AsCs3Li trigonal pyramids that share  a cornercorner with one Cs(1)Li2As3 trigonal bipyramid and corners with six equivalent As(1)Cs3Li trigonal pyramids.