data_Sc2SnSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.03
_cell_length_b   5.03
_cell_length_c   5.03
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Sc2SnSe
_chemical_formula_sum   'Sc2 Sn1 Se1'
_cell_volume   90.06
_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
  Sc  Sc0  1  0.0  0.0  0.0  1.0
  Sc  Sc1  1  0.34  0.34  0.34  1.0
  Sn  Sn3  1  0.78  0.78  0.78  1.0
  Se  Se2  1  0.56  0.56  0.56  1.0

data_Sc2SnSe
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.03
_cell_length_b   5.03
_cell_length_c   12.32
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Sc2SnSe
_chemical_formula_sum   'Sc6 Sn3 Se3'
_cell_volume   270.18
_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
  Sc  Sc0  3  0.0  0.0  0.0  1.0
  Sc  Sc1  3  0.0  0.0  0.66  1.0
  Sn  Sn2  3  0.0  0.0  0.22  1.0
  Se  Se3  3  0.0  0.0  0.44  1.0

Sc Sc Sn Se
Sc Sc Sn Se 0 2 - - - 0 2 - - o 0 2 o - - 0 2 - o - 0 3 - - o 0 3 - o - 0 3 o - - 0 1 - o o 0 1 o - o 0 1 o o - 1 3 o - o 1 3 - o o 1 3 o o - 1 3 o o o 1 2 - o o 1 2 o - o 1 2 o o - 2 3 o o o 2 3 o o + 2 3 + o o 2 3 o + o 
Sc2SnSe crystallizes in the trigonal R3m space group. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 10-coordinate geometry to three equivalent Sc(2), four equivalent Sn(1), and three equivalent Se(1) atoms. All Sc(1)-Sc(2) bond lengths are 2.91 Å. There is one shorter (2.73 Å) and three longer (3.22 Å) Sc(1)-Sn(1) bond lengths. All Sc(1)-Se(1) bond lengths are 3.20 Å. In the second Sc site, Sc(2) is bonded in a 1-coordinate geometry to three equivalent Sc(1), three equivalent Sn(1), and four equivalent Se(1) atoms. All Sc(2)-Sn(1) bond lengths are 3.20 Å. There is one shorter (2.73 Å) and three longer (3.22 Å) Sc(2)-Se(1) bond lengths. Sn(1) is bonded in a 11-coordinate geometry to three equivalent Sc(2), four equivalent Sc(1), and four equivalent Se(1) atoms. There is one shorter (2.73 Å) and three longer (3.22 Å) Sn(1)-Se(1) bond lengths. Se(1) is bonded in a 11-coordinate geometry to three equivalent Sc(1), four equivalent Sc(2), and four equivalent Sn(1) atoms.