data_YAsS3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.18
_cell_length_b   5.18
_cell_length_c   5.18
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   YAsS3
_chemical_formula_sum   'Y1 As1 S3'
_cell_volume   139.16
_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
  Y  Y0  1  0.59  0.59  0.59  1.0
  As  As1  1  0.0  0.0  0.0  1.0
  S  S2  1  0.59  0.0  0.59  1.0
  S  S3  1  0.59  0.59  0.0  1.0
  S  S4  1  0.0  0.59  0.59  1.0

data_YAsS3
_symmetry_space_group_name_H-M   R3m
_cell_length_a   7.33
_cell_length_b   7.33
_cell_length_c   8.98
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   YAsS3
_chemical_formula_sum   'Y3 As3 S9'
_cell_volume   417.49
_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
  Y  Y0  3  0.0  0.0  0.59  1.0
  As  As1  3  0.0  0.0  0.0  1.0
  S  S2  9  0.2  0.39  0.39  1.0

Y As S S S
Y As S S S 0 4 + o o 0 2 o + o 0 3 o o + 0 1 + + + 1 3 - - o 1 3 - o o 1 3 o - o 1 2 - o - 1 2 - o o 1 2 o o - 1 4 o - - 1 4 o - o 1 4 o o - 
YAsS3 crystallizes in the trigonal R3m space group. Y(1) is bonded to six equivalent S(1) atoms to form distorted corner-sharing YS6 octahedra. The corner-sharing octahedra are not tilted. There are three shorter (2.12 Å) and three longer (3.06 Å) Y(1)-S(1) bond lengths. As(1) is bonded in a 3-coordinate geometry to three equivalent S(1) atoms. All As(1)-S(1) bond lengths are 3.00 Å. S(1) is bonded in a distorted single-bond geometry to two equivalent Y(1) and one As(1) atom.