data_K3BiSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.97
_cell_length_b   9.97
_cell_length_c   9.97
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   K3BiSe3
_chemical_formula_sum   'K12 Bi4 Se12'
_cell_volume   990.61
_cell_formula_units_Z   4
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
  K  K0  1  0.2  0.2  0.2  1.0
  K  K1  1  0.78  0.77  0.18  1.0
  K  K2  1  0.18  0.78  0.77  1.0
  K  K3  1  0.77  0.18  0.78  1.0
  K  K4  1  0.72  0.72  0.72  1.0
  K  K5  1  0.23  0.25  0.73  1.0
  K  K6  1  0.73  0.23  0.25  1.0
  K  K7  1  0.25  0.73  0.23  1.0
  K  K8  1  0.1  0.1  0.1  1.0
  K  K9  1  0.85  0.87  0.12  1.0
  K  K10  1  0.12  0.85  0.87  1.0
  K  K11  1  0.87  0.12  0.85  1.0
  Bi  Bi12  1  0.33  0.33  0.33  1.0
  Bi  Bi13  1  0.66  0.64  0.31  1.0
  Bi  Bi14  1  0.31  0.66  0.64  1.0
  Bi  Bi15  1  0.64  0.31  0.66  1.0
  Se  Se16  1  0.24  0.08  0.98  1.0
  Se  Se17  1  0.98  0.24  0.08  1.0
  Se  Se18  1  0.08  0.98  0.24  1.0
  Se  Se19  1  0.87  0.99  0.23  1.0
  Se  Se20  1  0.96  0.74  0.89  1.0
  Se  Se21  1  0.89  0.96  0.74  1.0
  Se  Se22  1  0.01  0.73  0.09  1.0
  Se  Se23  1  0.99  0.23  0.87  1.0
  Se  Se24  1  0.09  0.01  0.73  1.0
  Se  Se25  1  0.23  0.87  0.99  1.0
  Se  Se26  1  0.73  0.09  0.01  1.0
  Se  Se27  1  0.74  0.89  0.96  1.0

data_K3BiSe3
_symmetry_space_group_name_H-M   R3
_cell_length_a   14.1
_cell_length_b   14.1
_cell_length_c   17.27
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   146
_chemical_formula_structural   K3BiSe3
_chemical_formula_sum   'K36 Bi12 Se36'
_cell_volume   2971.83
_cell_formula_units_Z   12
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  'x+1/3, y+2/3, z+2/3'
  5  '-y+1/3, x-y+2/3, z+2/3'
  6  '-x+y+1/3, -x+2/3, z+2/3'
  7  'x+2/3, y+1/3, z+1/3'
  8  '-y+2/3, x-y+1/3, z+1/3'
  9  '-x+y+2/3, -x+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
  K  K0  9  0.16  0.34  0.07  1.0
  K  K1  9  0.17  0.08  0.95  1.0
  K  K2  9  0.19  0.79  0.58  1.0
  K  K3  3  0.0  0.0  0.1  1.0
  K  K4  3  0.0  0.0  0.2  1.0
  K  K5  3  0.0  0.0  0.72  1.0
  Bi  Bi6  9  0.1  0.88  0.54  1.0
  Bi  Bi7  3  0.0  0.0  0.33  1.0
  Se  Se8  9  0.03  0.12  0.86  1.0
  Se  Se9  9  0.07  0.85  0.94  1.0
  Se  Se10  9  0.14  0.12  0.1  1.0
  Se  Se11  9  0.18  0.47  0.7  1.0

K K K K K K K K K K K K Bi Bi Bi Bi Se Se Se Se Se Se Se Se Se Se Se Se
K3BiSe3 crystallizes in the trigonal R3 space group. There are six inequivalent K sites. In the first K site, K(1) is bonded in a 5-coordinate geometry to one K(5), one Bi(1), and three equivalent Se(1) atoms. The K(1)-K(5) bond length is 1.69 Å. The K(1)-Bi(1) bond length is 2.19 Å. All K(1)-Se(1) bond lengths are 2.58 Å. In the second K site, K(2) is bonded in a 2-coordinate geometry to one K(6) and one Bi(2) atom. The K(2)-K(6) bond length is 1.36 Å. The K(2)-Bi(2) bond length is 2.19 Å. In the third K site, K(3) is bonded in a 6-coordinate geometry to three equivalent Bi(2) and three equivalent Se(3) atoms. All K(3)-Bi(2) bond lengths are 4.17 Å. All K(3)-Se(3) bond lengths are 2.96 Å. In the fourth K site, K(4) is bonded in a 3-coordinate geometry to one Se(1), one Se(2), and one Se(4) atom. The K(4)-Se(1) bond length is 2.95 Å. The K(4)-Se(2) bond length is 2.79 Å. The K(4)-Se(4) bond length is 2.78 Å. In the fifth K site, K(5) is bonded in a distorted trigonal planar geometry to one K(1) and three equivalent Se(1) atoms. All K(5)-Se(1) bond lengths are 1.90 Å. In the sixth K site, K(6) is bonded in a 4-coordinate geometry to one K(2), one Se(2), one Se(3), and one Se(4) atom. The K(6)-Se(2) bond length is 1.69 Å. The K(6)-Se(3) bond length is 1.93 Å. The K(6)-Se(4) bond length is 2.12 Å. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a single-bond geometry to one K(1) atom. In the second Bi site, Bi(2) is bonded in a single-bond geometry to one K(2) and one K(3) atom. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a single-bond geometry to one K(1), one K(4), and one K(5) atom. In the second Se site, Se(2) is bonded in a single-bond geometry to one K(4) and one K(6) atom. In the third Se site, Se(3) is bonded in a single-bond geometry to one K(3) and one K(6) atom. In the fourth Se site, Se(4) is bonded in a distorted single-bond geometry to one K(4) and one K(6) atom.