The structure described by FeSb6(Pb2Se7)2 crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to two equivalent Se(2) and four equivalent Se(3) atoms to form FeSe6 octahedra that share corners with two equivalent Pb(1)Se6 octahedra, edges with two equivalent Fe(1)Se6 octahedra, and edges with four equivalent Sb(2)Se5 square pyramids. The corner-sharing octahedral tilt angles are 36°. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Se(2), one Se(5), two equivalent Se(1), and two equivalent Se(4) atoms to form PbSe6 octahedra that share  a cornercorner with one Fe(1)Se6 octahedra, corners with two equivalent Sb(2)Se5 square pyramids, edges with two equivalent Pb(1)Se6 octahedra, edges with two equivalent Sb(1)Se5 square pyramids, and edges with two equivalent Sb(3)Se5 square pyramids. The corner-sharing octahedral tilt angles are 36°. In the second Pb site, Pb(2) is bonded in a 7-coordinate geometry to one Se(4), one Se(6), one Se(7), two equivalent Se(1), and two equivalent Se(3) atoms. There are three inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to one Se(1), two equivalent Se(5), and two equivalent Se(6) atoms to form SbSe5 square pyramids that share corners with two equivalent Sb(2)Se5 square pyramids, corners with two equivalent Sb(3)Se5 square pyramids, edges with two equivalent Pb(1)Se6 octahedra,  an edgeedge with one Sb(2)Se5 square pyramid,  an edgeedge with one Sb(3)Se5 square pyramid, and edges with two equivalent Sb(1)Se5 square pyramids. In the second Sb site, Sb(2) is bonded to one Se(3), two equivalent Se(2), and two equivalent Se(6) atoms to form distorted SbSe5 square pyramids that share corners with two equivalent Pb(1)Se6 octahedra, corners with two equivalent Sb(1)Se5 square pyramids, edges with two equivalent Fe(1)Se6 octahedra,  an edgeedge with one Sb(1)Se5 square pyramid, and edges with two equivalent Sb(2)Se5 square pyramids. The corner-sharing octahedral tilt angles range from 68-74°. In the third Sb site, Sb(3) is bonded to one Se(4), two equivalent Se(5), and two equivalent Se(7) atoms to form distorted SbSe5 square pyramids that share corners with two equivalent Sb(1)Se5 square pyramids, edges with two equivalent Pb(1)Se6 octahedra,  an edgeedge with one Sb(1)Se5 square pyramid, and edges with two equivalent Sb(3)Se5 square pyramids. There are seven inequivalent Se sites. In the first Se site, Se(4) is bonded in a 3-coordinate geometry to one Pb(2), two equivalent Pb(1), and one Sb(3) atom. In the second Se site, Se(5) is bonded to one Pb(1), two equivalent Sb(1), and two equivalent Sb(3) atoms to form distorted SeSb4Pb square pyramids that share corners with two equivalent Se(6)Sb4Pb square pyramids,  an edgeedge with one Se(6)Sb4Pb square pyramid, edges with two equivalent Se(5)Sb4Pb square pyramids, and edges with two equivalent Se(1)SbPb4 square pyramids. In the third Se site, Se(6) is bonded to one Pb(2), two equivalent Sb(1), and two equivalent Sb(2) atoms to form SeSb4Pb square pyramids that share corners with two equivalent Se(5)Sb4Pb square pyramids,  an edgeedge with one Se(5)Sb4Pb square pyramid, edges with two equivalent Se(3)Fe2SbPb2 square pyramids, edges with two equivalent Se(6)Sb4Pb square pyramids, and edges with two equivalent Se(1)SbPb4 square pyramids. In the fourth Se site, Se(7) is bonded in a distorted water-like geometry to one Pb(2) and two equivalent Sb(3) atoms. In the fifth Se site, Se(1) is bonded to two equivalent Pb(1), two equivalent Pb(2), and one Sb(1) atom to form distorted SeSbPb4 square pyramids that share corners with two equivalent Se(3)Fe2SbPb2 square pyramids,  an edgeedge with one Se(3)Fe2SbPb2 square pyramid, edges with two equivalent Se(5)Sb4Pb square pyramids, edges with two equivalent Se(6)Sb4Pb square pyramids, and edges with two equivalent Se(1)SbPb4 square pyramids. In the sixth Se site, Se(2) is bonded in a 4-coordinate geometry to one Fe(1), one Pb(1), and two equivalent Sb(2) atoms. In the seventh Se site, Se(3) is bonded to two equivalent Fe(1), two equivalent Pb(2), and one Sb(2) atom to form distorted SeFe2SbPb2 square pyramids that share corners with two equivalent Se(3)Fe2SbPb2 square pyramids, corners with two equivalent Se(1)SbPb4 square pyramids,  an edgeedge with one Se(1)SbPb4 square pyramid, edges with two equivalent Se(6)Sb4Pb square pyramids, and edges with three equivalent Se(3)Fe2SbPb2 square pyramids. is represented by the CIF card [CIF]
data_FeSb6(Pb2Se7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   20.155
_cell_length_b   4.146
_cell_length_c   16.842
_cell_angle_alpha   88.045
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1406.511
_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
  Fe  Fe0  1  0.000  0.500  0.000  1.0
  Fe  Fe1  1  0.500  0.500  0.500  1.0
  Sb  Sb2  1  0.549  0.095  0.103  1.0
  Sb  Sb3  1  0.049  0.905  0.397  1.0
  Sb  Sb4  1  0.451  0.905  0.897  1.0
  Sb  Sb5  1  0.951  0.095  0.603  1.0
  Sb  Sb6  1  0.934  0.935  0.181  1.0
  Sb  Sb7  1  0.434  0.065  0.319  1.0
  Sb  Sb8  1  0.066  0.065  0.819  1.0
  Sb  Sb9  1  0.566  0.935  0.681  1.0
  Sb  Sb10  1  0.660  0.091  0.867  1.0
  Sb  Sb11  1  0.160  0.909  0.633  1.0
  Sb  Sb12  1  0.340  0.909  0.133  1.0
  Sb  Sb13  1  0.840  0.091  0.367  1.0
  Pb  Pb14  1  0.737  0.548  0.064  1.0
  Pb  Pb15  1  0.237  0.452  0.436  1.0
  Pb  Pb16  1  0.263  0.452  0.936  1.0
  Pb  Pb17  1  0.763  0.548  0.564  1.0
  Pb  Pb18  1  0.635  0.528  0.310  1.0
  Pb  Pb19  1  0.135  0.472  0.190  1.0
  Pb  Pb20  1  0.365  0.472  0.690  1.0
  Pb  Pb21  1  0.865  0.528  0.810  1.0
  Se  Se22  1  0.663  0.044  0.181  1.0
  Se  Se23  1  0.163  0.956  0.319  1.0
  Se  Se24  1  0.337  0.956  0.819  1.0
  Se  Se25  1  0.837  0.044  0.681  1.0
  Se  Se26  1  0.895  0.487  0.078  1.0
  Se  Se27  1  0.395  0.513  0.422  1.0
  Se  Se28  1  0.105  0.513  0.922  1.0
  Se  Se29  1  0.605  0.487  0.578  1.0
  Se  Se30  1  0.543  0.021  0.407  1.0
  Se  Se31  1  0.043  0.979  0.093  1.0
  Se  Se32  1  0.457  0.979  0.593  1.0
  Se  Se33  1  0.957  0.021  0.907  1.0
  Se  Se34  1  0.773  0.063  0.944  1.0
  Se  Se35  1  0.273  0.937  0.556  1.0
  Se  Se36  1  0.227  0.937  0.056  1.0
  Se  Se37  1  0.727  0.063  0.444  1.0
  Se  Se38  1  0.599  0.554  0.994  1.0
  Se  Se39  1  0.099  0.446  0.506  1.0
  Se  Se40  1  0.401  0.446  0.006  1.0
  Se  Se41  1  0.901  0.554  0.494  1.0
  Se  Se42  1  0.503  0.529  0.215  1.0
  Se  Se43  1  0.003  0.471  0.285  1.0
  Se  Se44  1  0.497  0.471  0.785  1.0
  Se  Se45  1  0.997  0.529  0.715  1.0
  Se  Se46  1  0.797  0.587  0.272  1.0
  Se  Se47  1  0.297  0.413  0.228  1.0
  Se  Se48  1  0.203  0.413  0.728  1.0
  Se  Se49  1  0.703  0.587  0.772  1.0
[/CIF]
.
The structure described by FeSb6(Pb2Se7)2 crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to two equivalent Se(2) and four equivalent Se(3) atoms to form FeSe6 octahedra that share corners with two equivalent Pb(1)Se6 octahedra, edges with two equivalent Fe(1)Se6 octahedra, and edges with four equivalent Sb(2)Se5 square pyramids. The corner-sharing octahedral tilt angles are 36°. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Se(2), one Se(5), two equivalent Se(1), and two equivalent Se(4) atoms to form PbSe6 octahedra that share  a cornercorner with one Fe(1)Se6 octahedra, corners with two equivalent Sb(2)Se5 square pyramids, edges with two equivalent Pb(1)Se6 octahedra, edges with two equivalent Sb(1)Se5 square pyramids, and edges with two equivalent Sb(3)Se5 square pyramids. The corner-sharing octahedral tilt angles are 36°. In the second Pb site, Pb(2) is bonded in a 7-coordinate geometry to one Se(4), one Se(6), one Se(7), two equivalent Se(1), and two equivalent Se(3) atoms. There are three inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to one Se(1), two equivalent Se(5), and two equivalent Se(6) atoms to form SbSe5 square pyramids that share corners with two equivalent Sb(2)Se5 square pyramids, corners with two equivalent Sb(3)Se5 square pyramids, edges with two equivalent Pb(1)Se6 octahedra,  an edgeedge with one Sb(2)Se5 square pyramid,  an edgeedge with one Sb(3)Se5 square pyramid, and edges with two equivalent Sb(1)Se5 square pyramids. In the second Sb site, Sb(2) is bonded to one Se(3), two equivalent Se(2), and two equivalent Se(6) atoms to form distorted SbSe5 square pyramids that share corners with two equivalent Pb(1)Se6 octahedra, corners with two equivalent Sb(1)Se5 square pyramids, edges with two equivalent Fe(1)Se6 octahedra,  an edgeedge with one Sb(1)Se5 square pyramid, and edges with two equivalent Sb(2)Se5 square pyramids. The corner-sharing octahedral tilt angles range from 68-74°. In the third Sb site, Sb(3) is bonded to one Se(4), two equivalent Se(5), and two equivalent Se(7) atoms to form distorted SbSe5 square pyramids that share corners with two equivalent Sb(1)Se5 square pyramids, edges with two equivalent Pb(1)Se6 octahedra,  an edgeedge with one Sb(1)Se5 square pyramid, and edges with two equivalent Sb(3)Se5 square pyramids. There are seven inequivalent Se sites. In the first Se site, Se(4) is bonded in a 3-coordinate geometry to one Pb(2), two equivalent Pb(1), and one Sb(3) atom. In the second Se site, Se(5) is bonded to one Pb(1), two equivalent Sb(1), and two equivalent Sb(3) atoms to form distorted SeSb4Pb square pyramids that share corners with two equivalent Se(6)Sb4Pb square pyramids,  an edgeedge with one Se(6)Sb4Pb square pyramid, edges with two equivalent Se(5)Sb4Pb square pyramids, and edges with two equivalent Se(1)SbPb4 square pyramids. In the third Se site, Se(6) is bonded to one Pb(2), two equivalent Sb(1), and two equivalent Sb(2) atoms to form SeSb4Pb square pyramids that share corners with two equivalent Se(5)Sb4Pb square pyramids,  an edgeedge with one Se(5)Sb4Pb square pyramid, edges with two equivalent Se(3)Fe2SbPb2 square pyramids, edges with two equivalent Se(6)Sb4Pb square pyramids, and edges with two equivalent Se(1)SbPb4 square pyramids. In the fourth Se site, Se(7) is bonded in a distorted water-like geometry to one Pb(2) and two equivalent Sb(3) atoms. In the fifth Se site, Se(1) is bonded to two equivalent Pb(1), two equivalent Pb(2), and one Sb(1) atom to form distorted SeSbPb4 square pyramids that share corners with two equivalent Se(3)Fe2SbPb2 square pyramids,  an edgeedge with one Se(3)Fe2SbPb2 square pyramid, edges with two equivalent Se(5)Sb4Pb square pyramids, edges with two equivalent Se(6)Sb4Pb square pyramids, and edges with two equivalent Se(1)SbPb4 square pyramids. In the sixth Se site, Se(2) is bonded in a 4-coordinate geometry to one Fe(1), one Pb(1), and two equivalent Sb(2) atoms. In the seventh Se site, Se(3) is bonded to two equivalent Fe(1), two equivalent Pb(2), and one Sb(2) atom to form distorted SeFe2SbPb2 square pyramids that share corners with two equivalent Se(3)Fe2SbPb2 square pyramids, corners with two equivalent Se(1)SbPb4 square pyramids,  an edgeedge with one Se(1)SbPb4 square pyramid, edges with two equivalent Se(6)Sb4Pb square pyramids, and edges with three equivalent Se(3)Fe2SbPb2 square pyramids. is represented by the CIF card [CIF]
data_FeSb6(Pb2Se7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   20.155
_cell_length_b   4.146
_cell_length_c   16.842
_cell_angle_alpha   88.045
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1406.511
_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
  Fe  Fe0  1  0.000  0.500  0.000  1.0
  Fe  Fe1  1  0.500  0.500  0.500  1.0
  Sb  Sb2  1  0.549  0.095  0.103  1.0
  Sb  Sb3  1  0.049  0.905  0.397  1.0
  Sb  Sb4  1  0.451  0.905  0.897  1.0
  Sb  Sb5  1  0.951  0.095  0.603  1.0
  Sb  Sb6  1  0.934  0.935  0.181  1.0
  Sb  Sb7  1  0.434  0.065  0.319  1.0
  Sb  Sb8  1  0.066  0.065  0.819  1.0
  Sb  Sb9  1  0.566  0.935  0.681  1.0
  Sb  Sb10  1  0.660  0.091  0.867  1.0
  Sb  Sb11  1  0.160  0.909  0.633  1.0
  Sb  Sb12  1  0.340  0.909  0.133  1.0
  Sb  Sb13  1  0.840  0.091  0.367  1.0
  Pb  Pb14  1  0.737  0.548  0.064  1.0
  Pb  Pb15  1  0.237  0.452  0.436  1.0
  Pb  Pb16  1  0.263  0.452  0.936  1.0
  Pb  Pb17  1  0.763  0.548  0.564  1.0
  Pb  Pb18  1  0.635  0.528  0.310  1.0
  Pb  Pb19  1  0.135  0.472  0.190  1.0
  Pb  Pb20  1  0.365  0.472  0.690  1.0
  Pb  Pb21  1  0.865  0.528  0.810  1.0
  Se  Se22  1  0.663  0.044  0.181  1.0
  Se  Se23  1  0.163  0.956  0.319  1.0
  Se  Se24  1  0.337  0.956  0.819  1.0
  Se  Se25  1  0.837  0.044  0.681  1.0
  Se  Se26  1  0.895  0.487  0.078  1.0
  Se  Se27  1  0.395  0.513  0.422  1.0
  Se  Se28  1  0.105  0.513  0.922  1.0
  Se  Se29  1  0.605  0.487  0.578  1.0
  Se  Se30  1  0.543  0.021  0.407  1.0
  Se  Se31  1  0.043  0.979  0.093  1.0
  Se  Se32  1  0.457  0.979  0.593  1.0
  Se  Se33  1  0.957  0.021  0.907  1.0
  Se  Se34  1  0.773  0.063  0.944  1.0
  Se  Se35  1  0.273  0.937  0.556  1.0
  Se  Se36  1  0.227  0.937  0.056  1.0
  Se  Se37  1  0.727  0.063  0.444  1.0
  Se  Se38  1  0.599  0.554  0.994  1.0
  Se  Se39  1  0.099  0.446  0.506  1.0
  Se  Se40  1  0.401  0.446  0.006  1.0
  Se  Se41  1  0.901  0.554  0.494  1.0
  Se  Se42  1  0.503  0.529  0.215  1.0
  Se  Se43  1  0.003  0.471  0.285  1.0
  Se  Se44  1  0.497  0.471  0.785  1.0
  Se  Se45  1  0.997  0.529  0.715  1.0
  Se  Se46  1  0.797  0.587  0.272  1.0
  Se  Se47  1  0.297  0.413  0.228  1.0
  Se  Se48  1  0.203  0.413  0.728  1.0
  Se  Se49  1  0.703  0.587  0.772  1.0
[/CIF]
.