data_BaHgAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.32
_cell_length_b   5.32
_cell_length_c   5.32
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaHgAs
_chemical_formula_sum   'Ba1 Hg1 As1'
_cell_volume   106.21
_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
  Ba  Ba1  1  0.64  0.64  0.64  1.0
  Hg  Hg2  1  0.88  0.88  0.88  1.0
  As  As0  1  0.0  0.0  0.0  1.0

data_BaHgAs
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.32
_cell_length_b   5.32
_cell_length_c   13.02
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   BaHgAs
_chemical_formula_sum   'Ba3 Hg3 As3'
_cell_volume   318.64
_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
  Ba  Ba0  3  0.0  0.0  0.36  1.0
  Hg  Hg1  3  0.0  0.0  0.12  1.0
  As  As2  3  0.0  0.0  0.0  1.0

Ba Hg As
BaHgAs crystallizes in the trigonal R3m space group. Ba(1) is bonded to four equivalent Hg(1) and three equivalent As(1) atoms to form distorted BaHg4As3 hexagonal pyramids that share corners with six equivalent Ba(1)Hg4As3 hexagonal pyramids, corners with four equivalent As(1)Ba3Hg trigonal pyramids, and edges with six equivalent Ba(1)Hg4As3 hexagonal pyramids. There is one shorter (3.14 Å) and three longer (3.30 Å) Ba(1)-Hg(1) bond lengths. All Ba(1)-As(1) bond lengths are 3.09 Å. Hg(1) is bonded in a 5-coordinate geometry to four equivalent Ba(1) and one As(1) atom. The Hg(1)-As(1) bond length is 1.57 Å. As(1) is bonded to three equivalent Ba(1) and one Hg(1) atom to form distorted AsBa3Hg trigonal pyramids that share corners with four equivalent Ba(1)Hg4As3 hexagonal pyramids and corners with six equivalent As(1)Ba3Hg trigonal pyramids.