data_BaAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.37
_cell_length_b   10.37
_cell_length_c   10.37
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaAs2
_chemical_formula_sum   'Ba8 As16'
_cell_volume   787.86
_cell_formula_units_Z   8
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
  Ba  Ba16  1  0.58  0.41  0.41  1.0
  Ba  Ba17  1  0.41  0.58  0.41  1.0
  Ba  Ba18  1  0.41  0.41  0.58  1.0
  Ba  Ba19  1  0.58  0.58  0.58  1.0
  Ba  Ba20  1  0.74  0.92  0.92  1.0
  Ba  Ba21  1  0.92  0.74  0.92  1.0
  Ba  Ba22  1  0.92  0.92  0.74  1.0
  Ba  Ba23  1  0.74  0.74  0.74  1.0
  As  As0  1  0.83  0.83  0.83  1.0
  As  As1  1  0.5  0.5  0.83  1.0
  As  As2  1  0.5  0.83  0.5  1.0
  As  As3  1  0.83  0.5  0.5  1.0
  As  As4  1  0.33  0.33  0.16  1.0
  As  As5  1  0.33  0.16  0.33  1.0
  As  As6  1  0.5  0.33  0.33  1.0
  As  As7  1  0.16  0.33  0.33  1.0
  As  As8  1  0.33  0.5  0.33  1.0
  As  As9  1  0.33  0.33  0.5  1.0
  As  As10  1  0.67  0.67  0.5  1.0
  As  As11  1  0.67  0.5  0.67  1.0
  As  As12  1  0.83  0.67  0.67  1.0
  As  As13  1  0.5  0.67  0.67  1.0
  As  As14  1  0.67  0.83  0.67  1.0
  As  As15  1  0.67  0.67  0.83  1.0

data_BaAs2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   10.37
_cell_length_b   10.37
_cell_length_c   25.39
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   BaAs2
_chemical_formula_sum   'Ba24 As48'
_cell_volume   2363.57
_cell_formula_units_Z   24
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
  Ba  Ba0  9  0.06  0.12  0.53  1.0
  Ba  Ba1  9  0.12  0.06  0.14  1.0
  Ba  Ba2  3  0.0  0.0  0.26  1.0
  Ba  Ba3  3  0.0  0.0  0.42  1.0
  As  As4  9  0.05  0.11  0.28  1.0
  As  As5  9  0.06  0.11  0.61  1.0
  As  As6  9  0.11  0.05  0.39  1.0
  As  As7  9  0.11  0.56  0.06  1.0
  As  As8  9  0.11  0.06  0.72  1.0
  As  As9  3  0.0  0.0  0.17  1.0

Ba Ba Ba Ba Ba Ba Ba Ba As As As As As As As As As As As As As As As As
Ba Ba Ba Ba Ba Ba Ba Ba As As As As As As As As As As As As As As As As 0 14 o o o 0 2 o o o 0 1 o o o 1 16 o o o 1 2 o o o 2 17 o o o 3 21 o o o 3 19 o o o 3 18 o o o 4 8 o o o 5 8 o o o 6 8 o o o 7 23 o o o 7 22 o o o 7 20 o o o 9 21 o o o 9 19 o o o 10 21 o o o 10 18 o o o 11 19 o o o 11 18 o o o 12 13 o o o 12 15 o o o 13 15 o o o 14 17 o o o 14 16 o o o 16 17 o o o 
BaAs2 crystallizes in the trigonal R3m space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 1-coordinate geometry to one As(2) and one As(4) atom. The Ba(1)-As(2) bond length is 3.76 Å. The Ba(1)-As(4) bond length is 2.04 Å. In the second Ba site, Ba(2) is bonded in a distorted T-shaped geometry to three equivalent As(2) and three equivalent As(5) atoms. All Ba(2)-As(2) bond lengths are 2.10 Å. All Ba(2)-As(5) bond lengths are 1.18 Å. In the third Ba site, Ba(3) is bonded in a single-bond geometry to one As(1) atom. The Ba(3)-As(1) bond length is 1.27 Å. In the fourth Ba site, Ba(4) is bonded in a 4-coordinate geometry to one As(1) and three equivalent As(6) atoms. The Ba(4)-As(1) bond length is 2.30 Å. All Ba(4)-As(6) bond lengths are 1.13 Å. There are six inequivalent As sites. In the first As site, As(5) is bonded in a single-bond geometry to one Ba(2) and two equivalent As(2) atoms. Both As(5)-As(2) bond lengths are 1.74 Å. In the second As site, As(6) is bonded in a single-bond geometry to one Ba(4) and one As(2) atom. The As(6)-As(2) bond length is 2.98 Å. In the third As site, As(1) is bonded in a 4-coordinate geometry to one Ba(4) and three equivalent Ba(3) atoms. In the fourth As site, As(2) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one As(3), one As(6), and two equivalent As(5) atoms. The As(2)-As(3) bond length is 2.98 Å. In the fifth As site, As(3) is bonded in a 5-coordinate geometry to one As(2), two equivalent As(3), and two equivalent As(4) atoms. Both As(3)-As(3) bond lengths are 1.73 Å. Both As(3)-As(4) bond lengths are 2.99 Å. In the sixth As site, As(4) is bonded in a 3-coordinate geometry to one Ba(1), two equivalent As(3), and two equivalent As(4) atoms. Both As(4)-As(4) bond lengths are 1.73 Å.