data_La2As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.09
_cell_length_b   5.09
_cell_length_c   5.09
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   La2As
_chemical_formula_sum   'La2 As1'
_cell_volume   93.47
_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
  La  La1  1  0.4  0.4  0.4  1.0
  La  La2  1  0.8  0.8  0.8  1.0
  As  As0  1  0.0  0.0  0.0  1.0

data_La2As
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.09
_cell_length_b   5.09
_cell_length_c   12.48
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   La2As
_chemical_formula_sum   'La6 As3'
_cell_volume   280.4
_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
  La  La0  3  0.0  0.0  0.2  1.0
  La  La1  3  0.0  0.0  0.6  1.0
  As  As2  3  0.0  0.0  0.0  1.0

La La As
La La As 0 2 o o + 0 2 o + o 0 2 + o o 0 1 - o o 0 1 o - o 0 1 o o - 1 2 + + + 
La2As crystallizes in the trigonal R3m space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a distorted trigonal non-coplanar geometry to three equivalent As(1) atoms. All La(1)-As(1) bond lengths are 3.07 Å. In the second La site, La(2) is bonded in a distorted single-bond geometry to four equivalent As(1) atoms. There is one shorter (2.48 Å) and three longer (3.39 Å) La(2)-As(1) bond lengths. As(1) is bonded in a 7-coordinate geometry to three equivalent La(1) and four equivalent La(2) atoms.