data_CaLaSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.2
_cell_length_b   5.2
_cell_length_c   5.2
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaLaSe2
_chemical_formula_sum   'Ca1 La1 Se2'
_cell_volume   99.67
_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
  Ca  Ca0  1  0.0  0.0  0.0  1.0
  La  La1  1  0.84  0.84  0.84  1.0
  Se  Se2  1  0.68  0.68  0.68  1.0
  Se  Se3  1  0.52  0.52  0.52  1.0

data_CaLaSe2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.2
_cell_length_b   5.2
_cell_length_c   12.75
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CaLaSe2
_chemical_formula_sum   'Ca3 La3 Se6'
_cell_volume   299.0
_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
  Ca  Ca0  3  0.0  0.0  0.0  1.0
  La  La1  3  0.0  0.0  0.16  1.0
  Se  Se2  3  0.0  0.0  0.32  1.0
  Se  Se3  3  0.0  0.0  0.48  1.0

Ca La Se Se
CaLaSe2 crystallizes in the trigonal R3m space group. Ca(1) is bonded to one La(1) and three equivalent Se(1) atoms to form CaLaSe3 trigonal pyramids that share corners with six equivalent Ca(1)LaSe3 trigonal pyramids and edges with three equivalent Se(2)La3Se trigonal pyramids. The Ca(1)-La(1) bond length is 2.04 Å. All Ca(1)-Se(1) bond lengths are 3.01 Å. La(1) is bonded in a distorted single-bond geometry to one Ca(1), one Se(1), and three equivalent Se(2) atoms. The La(1)-Se(1) bond length is 2.04 Å. All La(1)-Se(2) bond lengths are 3.01 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted single-bond geometry to three equivalent Ca(1), one La(1), and one Se(2) atom. The Se(1)-Se(2) bond length is 2.04 Å. In the second Se site, Se(2) is bonded to three equivalent La(1) and one Se(1) atom to form SeLa3Se trigonal pyramids that share corners with six equivalent Se(2)La3Se trigonal pyramids and edges with three equivalent Ca(1)LaSe3 trigonal pyramids.