The structure described by Sr4Bi6Se13 crystallizes in the monoclinic P2_1/m space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one Se(10), one Se(12), two equivalent Se(1), and two equivalent Se(7) atoms to form SrSe6 octahedra that share  a cornercorner with one Bi(3)Se6 octahedra, corners with three equivalent Bi(6)Se6 octahedra, edges with two equivalent Sr(1)Se6 octahedra, edges with two equivalent Bi(2)Se6 octahedra, and edges with two equivalent Bi(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 4-59°. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one Se(13), one Se(6), two equivalent Se(5), two equivalent Se(7), and two equivalent Se(9) atoms. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one Se(13), one Se(8), two equivalent Se(2), two equivalent Se(5), and three equivalent Se(3) atoms. In the fourth Sr site, Sr(4) is bonded in a 8-coordinate geometry to one Se(11), one Se(8), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(4) atoms. There are six inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one Se(13), one Se(2), two equivalent Se(11), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 5°. In the second Bi site, Bi(2) is bonded to one Se(11), one Se(7), two equivalent Se(12), and two equivalent Se(13) atoms to form BiSe6 octahedra that share corners with two equivalent Bi(3)Se6 octahedra, edges with two equivalent Sr(1)Se6 octahedra, edges with two equivalent Bi(1)Se6 octahedra, edges with two equivalent Bi(2)Se6 octahedra, and edges with three equivalent Bi(3)Se6 octahedra. The corner-sharing octahedral tilt angles are 6°. In the third Bi site, Bi(3) is bonded to one Se(1), two equivalent Se(11), and three equivalent Se(12) atoms to form BiSe6 octahedra that share  a cornercorner with one Sr(1)Se6 octahedra, corners with two equivalent Bi(1)Se6 octahedra, corners with two equivalent Bi(2)Se6 octahedra,  an edgeedge with one Bi(1)Se6 octahedra, edges with two equivalent Sr(1)Se6 octahedra, edges with three equivalent Bi(2)Se6 octahedra, and edges with four equivalent Bi(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 4-6°. In the fourth Bi site, Bi(4) is bonded to one Se(8), one Se(9), two equivalent Se(4), and two equivalent Se(6) atoms to form BiSe6 octahedra that share corners with four equivalent Bi(5)Se5 square pyramids, edges with two equivalent Bi(4)Se6 octahedra, edges with two equivalent Bi(6)Se6 octahedra, and  an edgeedge with one Bi(5)Se5 square pyramid. In the fifth Bi site, Bi(5) is bonded to one Se(5), two equivalent Se(6), and two equivalent Se(8) atoms to form BiSe5 square pyramids that share corners with four equivalent Bi(4)Se6 octahedra,  an edgeedge with one Bi(4)Se6 octahedra, and edges with two equivalent Bi(5)Se5 square pyramids. The corner-sharing octahedral tilt angles range from 4-89°. In the sixth Bi site, Bi(6) is bonded to one Se(4), two equivalent Se(9), and three equivalent Se(10) atoms to form BiSe6 octahedra that share corners with three equivalent Sr(1)Se6 octahedra, edges with two equivalent Bi(4)Se6 octahedra, and edges with four equivalent Bi(6)Se6 octahedra. The corner-sharing octahedral tilt angles range from 58-59°. There are thirteen inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Sr(1), two equivalent Sr(4), and one Bi(3) atom to form SeSr4Bi square pyramids that share  a cornercorner with one Se(12)SrBi5 octahedra, corners with two equivalent Se(2)Sr4Bi square pyramids, corners with two equivalent Se(7)Sr4Bi square pyramids, corners with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, corners with two equivalent Se(8)Sr2Bi3 trigonal bipyramids, corners with two equivalent Se(10)SrBi3 trigonal pyramids, edges with two equivalent Se(11)SrBi5 octahedra, edges with two equivalent Se(12)SrBi5 octahedra,  an edgeedge with one Se(2)Sr4Bi square pyramid,  an edgeedge with one Se(7)Sr4Bi square pyramid, edges with two equivalent Se(1)Sr4Bi square pyramids, and  an edgeedge with one Se(4)Sr2Bi3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 1°. In the second Se site, Se(2) is bonded to two equivalent Sr(3), two equivalent Sr(4), and one Bi(1) atom to form SeSr4Bi square pyramids that share corners with two equivalent Se(1)Sr4Bi square pyramids, corners with two equivalent Se(5)Sr4Bi square pyramids, corners with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, corners with three equivalent Se(13)Sr2Bi3 trigonal bipyramids, edges with two equivalent Se(11)SrBi5 octahedra,  an edgeedge with one Se(1)Sr4Bi square pyramid,  an edgeedge with one Se(5)Sr4Bi square pyramid, edges with two equivalent Se(2)Sr4Bi square pyramids,  an edgeedge with one Se(4)Sr2Bi3 trigonal bipyramid, and edges with two equivalent Se(8)Sr2Bi3 trigonal bipyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to three equivalent Sr(3) and two equivalent Bi(1) atoms. In the fourth Se site, Se(4) is bonded to two equivalent Sr(4), one Bi(6), and two equivalent Bi(4) atoms to form distorted SeSr2Bi3 trigonal bipyramids that share corners with two equivalent Se(11)SrBi5 octahedra, corners with two equivalent Se(1)Sr4Bi square pyramids, corners with two equivalent Se(2)Sr4Bi square pyramids, corners with two equivalent Se(6)SrBi4 square pyramids, corners with three equivalent Se(10)SrBi3 trigonal pyramids,  an edgeedge with one Se(1)Sr4Bi square pyramid,  an edgeedge with one Se(2)Sr4Bi square pyramid,  an edgeedge with one Se(6)SrBi4 square pyramid, edges with two equivalent Se(9)Sr2Bi3 square pyramids, edges with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, and edges with two equivalent Se(8)Sr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 44°. In the fifth Se site, Se(5) is bonded to two equivalent Sr(2), two equivalent Sr(3), and one Bi(5) atom to form SeSr4Bi square pyramids that share corners with two equivalent Se(9)Sr2Bi3 square pyramids, corners with two equivalent Se(2)Sr4Bi square pyramids, corners with two equivalent Se(7)Sr4Bi square pyramids,  an edgeedge with one Se(9)Sr2Bi3 square pyramid,  an edgeedge with one Se(2)Sr4Bi square pyramid,  an edgeedge with one Se(7)Sr4Bi square pyramid, edges with two equivalent Se(5)Sr4Bi square pyramids, edges with two equivalent Se(6)SrBi4 square pyramids, edges with two equivalent Se(13)Sr2Bi3 trigonal bipyramids, and edges with two equivalent Se(8)Sr2Bi3 trigonal bipyramids. In the sixth Se site, Se(6) is bonded to one Sr(2), two equivalent Bi(4), and two equivalent Bi(5) atoms to form SeSrBi4 square pyramids that share corners with two equivalent Se(7)Sr4Bi square pyramids,  a cornercorner with one Se(13)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, corners with four equivalent Se(8)Sr2Bi3 trigonal bipyramids, edges with two equivalent Se(9)Sr2Bi3 square pyramids, edges with two equivalent Se(5)Sr4Bi square pyramids, edges with two equivalent Se(6)SrBi4 square pyramids,  an edgeedge with one Se(4)Sr2Bi3 trigonal bipyramid, and  an edgeedge with one Se(8)Sr2Bi3 trigonal bipyramid. In the seventh Se site, Se(7) is bonded to two equivalent Sr(1), two equivalent Sr(2), and one Bi(2) atom to form SeSr4Bi square pyramids that share  a cornercorner with one Se(11)SrBi5 octahedra, corners with two equivalent Se(9)Sr2Bi3 square pyramids, corners with two equivalent Se(1)Sr4Bi square pyramids, corners with two equivalent Se(5)Sr4Bi square pyramids, corners with two equivalent Se(6)SrBi4 square pyramids, corners with two equivalent Se(10)SrBi3 trigonal pyramids, edges with two equivalent Se(12)SrBi5 octahedra,  an edgeedge with one Se(9)Sr2Bi3 square pyramid,  an edgeedge with one Se(1)Sr4Bi square pyramid,  an edgeedge with one Se(5)Sr4Bi square pyramid, edges with two equivalent Se(7)Sr4Bi square pyramids, and edges with two equivalent Se(13)Sr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 4°. In the eighth Se site, Se(8) is bonded to one Sr(3), one Sr(4), one Bi(4), and two equivalent Bi(5) atoms to form SeSr2Bi3 trigonal bipyramids that share  a cornercorner with one Se(11)SrBi5 octahedra,  a cornercorner with one Se(9)Sr2Bi3 square pyramid, corners with two equivalent Se(1)Sr4Bi square pyramids, corners with four equivalent Se(6)SrBi4 square pyramids,  a cornercorner with one Se(13)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(8)Sr2Bi3 trigonal bipyramids,  an edgeedge with one Se(6)SrBi4 square pyramid, edges with two equivalent Se(2)Sr4Bi square pyramids, edges with two equivalent Se(5)Sr4Bi square pyramids, and edges with two equivalent Se(4)Sr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 41°. In the ninth Se site, Se(9) is bonded to two equivalent Sr(2), one Bi(4), and two equivalent Bi(6) atoms to form SeSr2Bi3 square pyramids that share corners with two equivalent Se(5)Sr4Bi square pyramids, corners with two equivalent Se(7)Sr4Bi square pyramids,  a cornercorner with one Se(8)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(13)Sr2Bi3 trigonal bipyramids, corners with four equivalent Se(10)SrBi3 trigonal pyramids,  an edgeedge with one Se(5)Sr4Bi square pyramid,  an edgeedge with one Se(7)Sr4Bi square pyramid, edges with two equivalent Se(9)Sr2Bi3 square pyramids, edges with two equivalent Se(6)SrBi4 square pyramids, edges with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, and  an edgeedge with one Se(10)SrBi3 trigonal pyramid. In the tenth Se site, Se(10) is bonded to one Sr(1) and three equivalent Bi(6) atoms to form distorted SeSrBi3 trigonal pyramids that share  a cornercorner with one Se(12)SrBi5 octahedra, corners with two equivalent Se(1)Sr4Bi square pyramids, corners with two equivalent Se(7)Sr4Bi square pyramids, corners with four equivalent Se(9)Sr2Bi3 square pyramids, corners with three equivalent Se(4)Sr2Bi3 trigonal bipyramids, corners with two equivalent Se(10)SrBi3 trigonal pyramids,  an edgeedge with one Se(9)Sr2Bi3 square pyramid, and edges with two equivalent Se(10)SrBi3 trigonal pyramids. The corner-sharing octahedral tilt angles are 2°. In the eleventh Se site, Se(11) is bonded to one Sr(4), one Bi(2), two equivalent Bi(1), and two equivalent Bi(3) atoms to form SeSrBi5 octahedra that share corners with two equivalent Se(12)SrBi5 octahedra,  a cornercorner with one Se(7)Sr4Bi square pyramid,  a cornercorner with one Se(8)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, edges with two equivalent Se(11)SrBi5 octahedra, edges with three equivalent Se(12)SrBi5 octahedra, edges with two equivalent Se(1)Sr4Bi square pyramids, edges with two equivalent Se(2)Sr4Bi square pyramids, and edges with two equivalent Se(13)Sr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 5°. In the twelfth Se site, Se(12) is bonded to one Sr(1), two equivalent Bi(2), and three equivalent Bi(3) atoms to form SeSrBi5 octahedra that share corners with two equivalent Se(11)SrBi5 octahedra,  a cornercorner with one Se(1)Sr4Bi square pyramid, corners with two equivalent Se(13)Sr2Bi3 trigonal bipyramids,  a cornercorner with one Se(10)SrBi3 trigonal pyramid, edges with three equivalent Se(11)SrBi5 octahedra, edges with four equivalent Se(12)SrBi5 octahedra, edges with two equivalent Se(1)Sr4Bi square pyramids, edges with two equivalent Se(7)Sr4Bi square pyramids, and  an edgeedge with one Se(13)Sr2Bi3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 5°. In the thirteenth Se site, Se(13) is bonded to one Sr(2), one Sr(3), one Bi(1), and two equivalent Bi(2) atoms to form SeSr2Bi3 trigonal bipyramids that share corners with two equivalent Se(12)SrBi5 octahedra,  a cornercorner with one Se(6)SrBi4 square pyramid, corners with two equivalent Se(9)Sr2Bi3 square pyramids, corners with three equivalent Se(2)Sr4Bi square pyramids,  a cornercorner with one Se(8)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(13)Sr2Bi3 trigonal bipyramids,  an edgeedge with one Se(12)SrBi5 octahedra, edges with two equivalent Se(11)SrBi5 octahedra, edges with two equivalent Se(5)Sr4Bi square pyramids, and edges with two equivalent Se(7)Sr4Bi square pyramids. The corner-sharing octahedral tilt angles are 7°. is represented by the CIF file [CIF]
data_Sr4Bi6Se13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.275
_cell_length_b   17.272
_cell_length_c   18.733
_cell_angle_alpha   89.585
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1383.137
_cell_formula_units_Z   2
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
  Sr  Sr0  1  0.250  0.512  0.246  1.0
  Sr  Sr1  1  0.750  0.488  0.754  1.0
  Sr  Sr2  1  0.250  0.771  0.180  1.0
  Sr  Sr3  1  0.750  0.229  0.820  1.0
  Sr  Sr4  1  0.250  0.987  0.340  1.0
  Sr  Sr5  1  0.750  0.013  0.660  1.0
  Sr  Sr6  1  0.250  0.243  0.271  1.0
  Sr  Sr7  1  0.750  0.757  0.729  1.0
  Bi  Bi8  1  0.750  0.171  0.478  1.0
  Bi  Bi9  1  0.250  0.829  0.522  1.0
  Bi  Bi10  1  0.250  0.327  0.620  1.0
  Bi  Bi11  1  0.750  0.673  0.380  1.0
  Bi  Bi12  1  0.250  0.583  0.578  1.0
  Bi  Bi13  1  0.750  0.417  0.422  1.0
  Bi  Bi14  1  0.750  0.813  0.956  1.0
  Bi  Bi15  1  0.250  0.187  0.044  1.0
  Bi  Bi16  1  0.250  0.010  0.880  1.0
  Bi  Bi17  1  0.750  0.990  0.120  1.0
  Bi  Bi18  1  0.250  0.607  0.981  1.0
  Bi  Bi19  1  0.750  0.393  0.019  1.0
  Se  Se20  1  0.750  0.383  0.277  1.0
  Se  Se21  1  0.250  0.617  0.723  1.0
  Se  Se22  1  0.750  0.124  0.335  1.0
  Se  Se23  1  0.250  0.876  0.665  1.0
  Se  Se24  1  0.750  0.930  0.485  1.0
  Se  Se25  1  0.250  0.070  0.515  1.0
  Se  Se26  1  0.750  0.265  0.126  1.0
  Se  Se27  1  0.250  0.735  0.874  1.0
  Se  Se28  1  0.750  0.894  0.238  1.0
  Se  Se29  1  0.250  0.106  0.762  1.0
  Se  Se30  1  0.250  0.894  0.039  1.0
  Se  Se31  1  0.750  0.106  0.961  1.0
  Se  Se32  1  0.750  0.642  0.236  1.0
  Se  Se33  1  0.250  0.358  0.764  1.0
  Se  Se34  1  0.750  0.920  0.822  1.0
  Se  Se35  1  0.250  0.080  0.178  1.0
  Se  Se36  1  0.750  0.695  0.061  1.0
  Se  Se37  1  0.250  0.305  0.939  1.0
  Se  Se38  1  0.750  0.521  0.913  1.0
  Se  Se39  1  0.250  0.479  0.087  1.0
  Se  Se40  1  0.250  0.302  0.444  1.0
  Se  Se41  1  0.750  0.698  0.556  1.0
  Se  Se42  1  0.250  0.540  0.410  1.0
  Se  Se43  1  0.750  0.460  0.590  1.0
  Se  Se44  1  0.250  0.780  0.361  1.0
  Se  Se45  1  0.750  0.220  0.639  1.0
[/CIF]
.
The structure described by Sr4Bi6Se13 crystallizes in the monoclinic P2_1/m space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one Se(10), one Se(12), two equivalent Se(1), and two equivalent Se(7) atoms to form SrSe6 octahedra that share  a cornercorner with one Bi(3)Se6 octahedra, corners with three equivalent Bi(6)Se6 octahedra, edges with two equivalent Sr(1)Se6 octahedra, edges with two equivalent Bi(2)Se6 octahedra, and edges with two equivalent Bi(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 4-59°. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one Se(13), one Se(6), two equivalent Se(5), two equivalent Se(7), and two equivalent Se(9) atoms. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one Se(13), one Se(8), two equivalent Se(2), two equivalent Se(5), and three equivalent Se(3) atoms. In the fourth Sr site, Sr(4) is bonded in a 8-coordinate geometry to one Se(11), one Se(8), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(4) atoms. There are six inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one Se(13), one Se(2), two equivalent Se(11), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 5°. In the second Bi site, Bi(2) is bonded to one Se(11), one Se(7), two equivalent Se(12), and two equivalent Se(13) atoms to form BiSe6 octahedra that share corners with two equivalent Bi(3)Se6 octahedra, edges with two equivalent Sr(1)Se6 octahedra, edges with two equivalent Bi(1)Se6 octahedra, edges with two equivalent Bi(2)Se6 octahedra, and edges with three equivalent Bi(3)Se6 octahedra. The corner-sharing octahedral tilt angles are 6°. In the third Bi site, Bi(3) is bonded to one Se(1), two equivalent Se(11), and three equivalent Se(12) atoms to form BiSe6 octahedra that share  a cornercorner with one Sr(1)Se6 octahedra, corners with two equivalent Bi(1)Se6 octahedra, corners with two equivalent Bi(2)Se6 octahedra,  an edgeedge with one Bi(1)Se6 octahedra, edges with two equivalent Sr(1)Se6 octahedra, edges with three equivalent Bi(2)Se6 octahedra, and edges with four equivalent Bi(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 4-6°. In the fourth Bi site, Bi(4) is bonded to one Se(8), one Se(9), two equivalent Se(4), and two equivalent Se(6) atoms to form BiSe6 octahedra that share corners with four equivalent Bi(5)Se5 square pyramids, edges with two equivalent Bi(4)Se6 octahedra, edges with two equivalent Bi(6)Se6 octahedra, and  an edgeedge with one Bi(5)Se5 square pyramid. In the fifth Bi site, Bi(5) is bonded to one Se(5), two equivalent Se(6), and two equivalent Se(8) atoms to form BiSe5 square pyramids that share corners with four equivalent Bi(4)Se6 octahedra,  an edgeedge with one Bi(4)Se6 octahedra, and edges with two equivalent Bi(5)Se5 square pyramids. The corner-sharing octahedral tilt angles range from 4-89°. In the sixth Bi site, Bi(6) is bonded to one Se(4), two equivalent Se(9), and three equivalent Se(10) atoms to form BiSe6 octahedra that share corners with three equivalent Sr(1)Se6 octahedra, edges with two equivalent Bi(4)Se6 octahedra, and edges with four equivalent Bi(6)Se6 octahedra. The corner-sharing octahedral tilt angles range from 58-59°. There are thirteen inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Sr(1), two equivalent Sr(4), and one Bi(3) atom to form SeSr4Bi square pyramids that share  a cornercorner with one Se(12)SrBi5 octahedra, corners with two equivalent Se(2)Sr4Bi square pyramids, corners with two equivalent Se(7)Sr4Bi square pyramids, corners with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, corners with two equivalent Se(8)Sr2Bi3 trigonal bipyramids, corners with two equivalent Se(10)SrBi3 trigonal pyramids, edges with two equivalent Se(11)SrBi5 octahedra, edges with two equivalent Se(12)SrBi5 octahedra,  an edgeedge with one Se(2)Sr4Bi square pyramid,  an edgeedge with one Se(7)Sr4Bi square pyramid, edges with two equivalent Se(1)Sr4Bi square pyramids, and  an edgeedge with one Se(4)Sr2Bi3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 1°. In the second Se site, Se(2) is bonded to two equivalent Sr(3), two equivalent Sr(4), and one Bi(1) atom to form SeSr4Bi square pyramids that share corners with two equivalent Se(1)Sr4Bi square pyramids, corners with two equivalent Se(5)Sr4Bi square pyramids, corners with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, corners with three equivalent Se(13)Sr2Bi3 trigonal bipyramids, edges with two equivalent Se(11)SrBi5 octahedra,  an edgeedge with one Se(1)Sr4Bi square pyramid,  an edgeedge with one Se(5)Sr4Bi square pyramid, edges with two equivalent Se(2)Sr4Bi square pyramids,  an edgeedge with one Se(4)Sr2Bi3 trigonal bipyramid, and edges with two equivalent Se(8)Sr2Bi3 trigonal bipyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to three equivalent Sr(3) and two equivalent Bi(1) atoms. In the fourth Se site, Se(4) is bonded to two equivalent Sr(4), one Bi(6), and two equivalent Bi(4) atoms to form distorted SeSr2Bi3 trigonal bipyramids that share corners with two equivalent Se(11)SrBi5 octahedra, corners with two equivalent Se(1)Sr4Bi square pyramids, corners with two equivalent Se(2)Sr4Bi square pyramids, corners with two equivalent Se(6)SrBi4 square pyramids, corners with three equivalent Se(10)SrBi3 trigonal pyramids,  an edgeedge with one Se(1)Sr4Bi square pyramid,  an edgeedge with one Se(2)Sr4Bi square pyramid,  an edgeedge with one Se(6)SrBi4 square pyramid, edges with two equivalent Se(9)Sr2Bi3 square pyramids, edges with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, and edges with two equivalent Se(8)Sr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 44°. In the fifth Se site, Se(5) is bonded to two equivalent Sr(2), two equivalent Sr(3), and one Bi(5) atom to form SeSr4Bi square pyramids that share corners with two equivalent Se(9)Sr2Bi3 square pyramids, corners with two equivalent Se(2)Sr4Bi square pyramids, corners with two equivalent Se(7)Sr4Bi square pyramids,  an edgeedge with one Se(9)Sr2Bi3 square pyramid,  an edgeedge with one Se(2)Sr4Bi square pyramid,  an edgeedge with one Se(7)Sr4Bi square pyramid, edges with two equivalent Se(5)Sr4Bi square pyramids, edges with two equivalent Se(6)SrBi4 square pyramids, edges with two equivalent Se(13)Sr2Bi3 trigonal bipyramids, and edges with two equivalent Se(8)Sr2Bi3 trigonal bipyramids. In the sixth Se site, Se(6) is bonded to one Sr(2), two equivalent Bi(4), and two equivalent Bi(5) atoms to form SeSrBi4 square pyramids that share corners with two equivalent Se(7)Sr4Bi square pyramids,  a cornercorner with one Se(13)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, corners with four equivalent Se(8)Sr2Bi3 trigonal bipyramids, edges with two equivalent Se(9)Sr2Bi3 square pyramids, edges with two equivalent Se(5)Sr4Bi square pyramids, edges with two equivalent Se(6)SrBi4 square pyramids,  an edgeedge with one Se(4)Sr2Bi3 trigonal bipyramid, and  an edgeedge with one Se(8)Sr2Bi3 trigonal bipyramid. In the seventh Se site, Se(7) is bonded to two equivalent Sr(1), two equivalent Sr(2), and one Bi(2) atom to form SeSr4Bi square pyramids that share  a cornercorner with one Se(11)SrBi5 octahedra, corners with two equivalent Se(9)Sr2Bi3 square pyramids, corners with two equivalent Se(1)Sr4Bi square pyramids, corners with two equivalent Se(5)Sr4Bi square pyramids, corners with two equivalent Se(6)SrBi4 square pyramids, corners with two equivalent Se(10)SrBi3 trigonal pyramids, edges with two equivalent Se(12)SrBi5 octahedra,  an edgeedge with one Se(9)Sr2Bi3 square pyramid,  an edgeedge with one Se(1)Sr4Bi square pyramid,  an edgeedge with one Se(5)Sr4Bi square pyramid, edges with two equivalent Se(7)Sr4Bi square pyramids, and edges with two equivalent Se(13)Sr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 4°. In the eighth Se site, Se(8) is bonded to one Sr(3), one Sr(4), one Bi(4), and two equivalent Bi(5) atoms to form SeSr2Bi3 trigonal bipyramids that share  a cornercorner with one Se(11)SrBi5 octahedra,  a cornercorner with one Se(9)Sr2Bi3 square pyramid, corners with two equivalent Se(1)Sr4Bi square pyramids, corners with four equivalent Se(6)SrBi4 square pyramids,  a cornercorner with one Se(13)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(8)Sr2Bi3 trigonal bipyramids,  an edgeedge with one Se(6)SrBi4 square pyramid, edges with two equivalent Se(2)Sr4Bi square pyramids, edges with two equivalent Se(5)Sr4Bi square pyramids, and edges with two equivalent Se(4)Sr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 41°. In the ninth Se site, Se(9) is bonded to two equivalent Sr(2), one Bi(4), and two equivalent Bi(6) atoms to form SeSr2Bi3 square pyramids that share corners with two equivalent Se(5)Sr4Bi square pyramids, corners with two equivalent Se(7)Sr4Bi square pyramids,  a cornercorner with one Se(8)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(13)Sr2Bi3 trigonal bipyramids, corners with four equivalent Se(10)SrBi3 trigonal pyramids,  an edgeedge with one Se(5)Sr4Bi square pyramid,  an edgeedge with one Se(7)Sr4Bi square pyramid, edges with two equivalent Se(9)Sr2Bi3 square pyramids, edges with two equivalent Se(6)SrBi4 square pyramids, edges with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, and  an edgeedge with one Se(10)SrBi3 trigonal pyramid. In the tenth Se site, Se(10) is bonded to one Sr(1) and three equivalent Bi(6) atoms to form distorted SeSrBi3 trigonal pyramids that share  a cornercorner with one Se(12)SrBi5 octahedra, corners with two equivalent Se(1)Sr4Bi square pyramids, corners with two equivalent Se(7)Sr4Bi square pyramids, corners with four equivalent Se(9)Sr2Bi3 square pyramids, corners with three equivalent Se(4)Sr2Bi3 trigonal bipyramids, corners with two equivalent Se(10)SrBi3 trigonal pyramids,  an edgeedge with one Se(9)Sr2Bi3 square pyramid, and edges with two equivalent Se(10)SrBi3 trigonal pyramids. The corner-sharing octahedral tilt angles are 2°. In the eleventh Se site, Se(11) is bonded to one Sr(4), one Bi(2), two equivalent Bi(1), and two equivalent Bi(3) atoms to form SeSrBi5 octahedra that share corners with two equivalent Se(12)SrBi5 octahedra,  a cornercorner with one Se(7)Sr4Bi square pyramid,  a cornercorner with one Se(8)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(4)Sr2Bi3 trigonal bipyramids, edges with two equivalent Se(11)SrBi5 octahedra, edges with three equivalent Se(12)SrBi5 octahedra, edges with two equivalent Se(1)Sr4Bi square pyramids, edges with two equivalent Se(2)Sr4Bi square pyramids, and edges with two equivalent Se(13)Sr2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 5°. In the twelfth Se site, Se(12) is bonded to one Sr(1), two equivalent Bi(2), and three equivalent Bi(3) atoms to form SeSrBi5 octahedra that share corners with two equivalent Se(11)SrBi5 octahedra,  a cornercorner with one Se(1)Sr4Bi square pyramid, corners with two equivalent Se(13)Sr2Bi3 trigonal bipyramids,  a cornercorner with one Se(10)SrBi3 trigonal pyramid, edges with three equivalent Se(11)SrBi5 octahedra, edges with four equivalent Se(12)SrBi5 octahedra, edges with two equivalent Se(1)Sr4Bi square pyramids, edges with two equivalent Se(7)Sr4Bi square pyramids, and  an edgeedge with one Se(13)Sr2Bi3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 5°. In the thirteenth Se site, Se(13) is bonded to one Sr(2), one Sr(3), one Bi(1), and two equivalent Bi(2) atoms to form SeSr2Bi3 trigonal bipyramids that share corners with two equivalent Se(12)SrBi5 octahedra,  a cornercorner with one Se(6)SrBi4 square pyramid, corners with two equivalent Se(9)Sr2Bi3 square pyramids, corners with three equivalent Se(2)Sr4Bi square pyramids,  a cornercorner with one Se(8)Sr2Bi3 trigonal bipyramid, corners with two equivalent Se(13)Sr2Bi3 trigonal bipyramids,  an edgeedge with one Se(12)SrBi5 octahedra, edges with two equivalent Se(11)SrBi5 octahedra, edges with two equivalent Se(5)Sr4Bi square pyramids, and edges with two equivalent Se(7)Sr4Bi square pyramids. The corner-sharing octahedral tilt angles are 7°. is represented by the CIF file [CIF]
data_Sr4Bi6Se13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.275
_cell_length_b   17.272
_cell_length_c   18.733
_cell_angle_alpha   89.585
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1383.137
_cell_formula_units_Z   2
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
  Sr  Sr0  1  0.250  0.512  0.246  1.0
  Sr  Sr1  1  0.750  0.488  0.754  1.0
  Sr  Sr2  1  0.250  0.771  0.180  1.0
  Sr  Sr3  1  0.750  0.229  0.820  1.0
  Sr  Sr4  1  0.250  0.987  0.340  1.0
  Sr  Sr5  1  0.750  0.013  0.660  1.0
  Sr  Sr6  1  0.250  0.243  0.271  1.0
  Sr  Sr7  1  0.750  0.757  0.729  1.0
  Bi  Bi8  1  0.750  0.171  0.478  1.0
  Bi  Bi9  1  0.250  0.829  0.522  1.0
  Bi  Bi10  1  0.250  0.327  0.620  1.0
  Bi  Bi11  1  0.750  0.673  0.380  1.0
  Bi  Bi12  1  0.250  0.583  0.578  1.0
  Bi  Bi13  1  0.750  0.417  0.422  1.0
  Bi  Bi14  1  0.750  0.813  0.956  1.0
  Bi  Bi15  1  0.250  0.187  0.044  1.0
  Bi  Bi16  1  0.250  0.010  0.880  1.0
  Bi  Bi17  1  0.750  0.990  0.120  1.0
  Bi  Bi18  1  0.250  0.607  0.981  1.0
  Bi  Bi19  1  0.750  0.393  0.019  1.0
  Se  Se20  1  0.750  0.383  0.277  1.0
  Se  Se21  1  0.250  0.617  0.723  1.0
  Se  Se22  1  0.750  0.124  0.335  1.0
  Se  Se23  1  0.250  0.876  0.665  1.0
  Se  Se24  1  0.750  0.930  0.485  1.0
  Se  Se25  1  0.250  0.070  0.515  1.0
  Se  Se26  1  0.750  0.265  0.126  1.0
  Se  Se27  1  0.250  0.735  0.874  1.0
  Se  Se28  1  0.750  0.894  0.238  1.0
  Se  Se29  1  0.250  0.106  0.762  1.0
  Se  Se30  1  0.250  0.894  0.039  1.0
  Se  Se31  1  0.750  0.106  0.961  1.0
  Se  Se32  1  0.750  0.642  0.236  1.0
  Se  Se33  1  0.250  0.358  0.764  1.0
  Se  Se34  1  0.750  0.920  0.822  1.0
  Se  Se35  1  0.250  0.080  0.178  1.0
  Se  Se36  1  0.750  0.695  0.061  1.0
  Se  Se37  1  0.250  0.305  0.939  1.0
  Se  Se38  1  0.750  0.521  0.913  1.0
  Se  Se39  1  0.250  0.479  0.087  1.0
  Se  Se40  1  0.250  0.302  0.444  1.0
  Se  Se41  1  0.750  0.698  0.556  1.0
  Se  Se42  1  0.250  0.540  0.410  1.0
  Se  Se43  1  0.750  0.460  0.590  1.0
  Se  Se44  1  0.250  0.780  0.361  1.0
  Se  Se45  1  0.750  0.220  0.639  1.0
[/CIF]
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