data_BaAsOs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.77
_cell_length_b   4.77
_cell_length_c   4.77
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaAsOs
_chemical_formula_sum   'Ba1 As1 Os1'
_cell_volume   76.55
_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  0.37  0.37  0.37  1.0
  As  As0  1  0.0  0.0  0.0  1.0
  Os  Os2  1  0.69  0.69  0.69  1.0

data_BaAsOs
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.77
_cell_length_b   4.77
_cell_length_c   11.67
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   BaAsOs
_chemical_formula_sum   'Ba3 As3 Os3'
_cell_volume   229.66
_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  0.63  1.0
  As  As1  3  0.0  0.0  -0.0  1.0
  Os  Os2  3  0.0  0.0  0.31  1.0

Ba As Os
Ba As Os 0 1 o o + 0 1 o + o 0 1 + o o 0 2 - o o 0 2 o - o 0 2 o o - 1 2 - - o 1 2 - o - 1 2 o - - 
BaOsAs is half-Heusler structured and crystallizes in the trigonal R3m space group. Ba(1) is bonded to four equivalent Os(1) and three equivalent As(1) atoms to form BaAs3Os4 hexagonal pyramids that share corners with three equivalent Os(1)Ba4As3 hexagonal pyramids, corners with six equivalent Ba(1)As3Os4 hexagonal pyramids, edges with three equivalent Os(1)Ba4As3 hexagonal pyramids, and edges with six equivalent Ba(1)As3Os4 hexagonal pyramids. There are three shorter (2.76 Å) and one longer (3.68 Å) Ba(1)-Os(1) bond length. All Ba(1)-As(1) bond lengths are 2.79 Å. Os(1) is bonded to four equivalent Ba(1) and three equivalent As(1) atoms to form distorted OsBa4As3 hexagonal pyramids that share corners with three equivalent Ba(1)As3Os4 hexagonal pyramids, corners with six equivalent Os(1)Ba4As3 hexagonal pyramids, edges with three equivalent Ba(1)As3Os4 hexagonal pyramids, and edges with six equivalent Os(1)Ba4As3 hexagonal pyramids. All Os(1)-As(1) bond lengths are 2.76 Å. As(1) is bonded in a distorted hexagonal planar geometry to three equivalent Ba(1) and three equivalent Os(1) atoms.