data_Y2CrSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.06
_cell_length_b   5.06
_cell_length_c   5.06
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Y2CrSe
_chemical_formula_sum   'Y2 Cr1 Se1'
_cell_volume   91.72
_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  Y2  1  0.58  0.58  0.58  1.0
  Y  Y3  1  0.37  0.37  0.37  1.0
  Cr  Cr0  1  0.0  0.0  0.0  1.0
  Se  Se1  1  0.79  0.79  0.79  1.0

data_Y2CrSe
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.06
_cell_length_b   5.06
_cell_length_c   12.4
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Y2CrSe
_chemical_formula_sum   'Y6 Cr3 Se3'
_cell_volume   275.17
_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  0.42  1.0
  Y  Y1  3  0.0  0.0  0.63  1.0
  Cr  Cr2  3  0.0  0.0  0.0  1.0
  Se  Se3  3  0.0  0.0  0.21  1.0

Y Y Cr Se
Y Y Cr Se 0 1 o o o 0 1 o o + 0 1 + o o 0 1 o + o 0 3 o - o 0 3 - o o 0 3 o o - 0 3 o o o 0 2 o + + 0 2 + o + 0 2 + + o 1 2 o o + 1 2 o + o 1 2 + o o 1 3 - o o 1 3 o - o 1 3 o o - 2 3 - - - 2 3 - - o 2 3 o - - 2 3 - o - 
Y2CrSe crystallizes in the trigonal R3m space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a distorted single-bond geometry to one Y(2) and one Se(1) atom. The Y(1)-Y(2) bond length is 2.61 Å. The Y(1)-Se(1) bond length is 2.61 Å. In the second Y site, Y(2) is bonded in a 7-coordinate geometry to one Y(1), three equivalent Cr(1), and three equivalent Se(1) atoms. All Y(2)-Cr(1) bond lengths are 2.96 Å. All Y(2)-Se(1) bond lengths are 3.12 Å. Cr(1) is bonded in a 1-coordinate geometry to three equivalent Y(2) and one Se(1) atom. The Cr(1)-Se(1) bond length is 2.61 Å. Se(1) is bonded in a 2-coordinate geometry to one Y(1), three equivalent Y(2), and one Cr(1) atom.