The material structure described by Ba4SiSb2Se11 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one Se(1), one Se(7), one Se(8), two equivalent Se(4), two equivalent Se(5), and two equivalent Se(6) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one Se(1), one Se(2), one Se(5), one Se(7), one Se(8), two equivalent Se(3), and two equivalent Se(9) atoms. Si(1) is bonded to one Se(8), one Se(9), and two equivalent Se(7) atoms to form SiSe4 tetrahedra that share  an edgeedge with one Sb(2)Se5 square pyramid. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a distorted see-saw-like geometry to one Se(3), one Se(4), and two equivalent Se(5) atoms. In the second Sb site, Sb(2) is bonded to one Se(6), two equivalent Se(5), and two equivalent Se(7) atoms to form distorted SbSe5 square pyramids that share  an edgeedge with one Si(1)Se4 tetrahedra. There are nine inequivalent Se sites. In the first Se site, Se(3) is bonded to four equivalent Ba(2), one Sb(1), and one Se(2) atom to form distorted SeBa4SbSe octahedra that share  a cornercorner with one Se(4)Ba4Sb square pyramid, corners with four equivalent Se(8)Ba4Si square pyramids, corners with four equivalent Se(9)Ba4Si square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with four equivalent Se(7)Ba2SiSb trigonal pyramids, edges with two equivalent Se(3)Ba4SbSe octahedra, edges with two equivalent Se(9)Ba4Si square pyramids,  an edgeedge with one Se(1)Ba4Se trigonal bipyramid, edges with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, and  a faceface with one Se(1)Ba4Se trigonal bipyramid. In the second Se site, Se(4) is bonded to four equivalent Ba(1) and one Sb(1) atom to form SeBa4Sb square pyramids that share  a cornercorner with one Se(3)Ba4SbSe octahedra, corners with two equivalent Se(8)Ba4Si square pyramids, corners with four equivalent Se(4)Ba4Sb square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with two equivalent Se(1)Ba4Se trigonal bipyramids, corners with four equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(8)Ba4Si square pyramid, edges with four equivalent Se(6)Ba4Sb square pyramids,  an edgeedge with one Se(1)Ba4Se trigonal bipyramid, and edges with four equivalent Se(5)Ba3Sb2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 25°. In the third Se site, Se(5) is bonded to one Ba(2), two equivalent Ba(1), one Sb(1), and one Sb(2) atom to form distorted SeBa3Sb2 trigonal bipyramids that share  a cornercorner with one Se(3)Ba4SbSe octahedra,  a cornercorner with one Se(4)Ba4Sb square pyramid,  a cornercorner with one Se(6)Ba4Sb square pyramid,  a cornercorner with one Se(8)Ba4Si square pyramid, corners with two equivalent Se(9)Ba4Si square pyramids,  a cornercorner with one Se(1)Ba4Se trigonal bipyramid, corners with four equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with five equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(3)Ba4SbSe octahedra,  an edgeedge with one Se(8)Ba4Si square pyramid, edges with two equivalent Se(4)Ba4Sb square pyramids, edges with two equivalent Se(6)Ba4Sb square pyramids, and  an edgeedge with one Se(1)Ba4Se trigonal bipyramid. The corner-sharing octahedral tilt angles are 52°. In the fourth Se site, Se(6) is bonded to four equivalent Ba(1) and one Sb(2) atom to form distorted SeBa4Sb square pyramids that share corners with two equivalent Se(8)Ba4Si square pyramids, corners with four equivalent Se(6)Ba4Sb square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with two equivalent Se(1)Ba4Se trigonal bipyramids, corners with two equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(8)Ba4Si square pyramid, edges with four equivalent Se(4)Ba4Sb square pyramids,  an edgeedge with one Se(1)Ba4Se trigonal bipyramid, edges with four equivalent Se(5)Ba3Sb2 trigonal bipyramids, and edges with two equivalent Se(7)Ba2SiSb trigonal pyramids. In the fifth Se site, Se(7) is bonded to one Ba(1), one Ba(2), one Si(1), and one Sb(2) atom to form distorted SeBa2SiSb trigonal pyramids that share corners with two equivalent Se(3)Ba4SbSe octahedra,  a cornercorner with one Se(6)Ba4Sb square pyramid,  a cornercorner with one Se(8)Ba4Si square pyramid,  a cornercorner with one Se(9)Ba4Si square pyramid, corners with two equivalent Se(4)Ba4Sb square pyramids, corners with two equivalent Se(1)Ba4Se trigonal bipyramids, corners with five equivalent Se(5)Ba3Sb2 trigonal bipyramids,  an edgeedge with one Se(6)Ba4Sb square pyramid,  an edgeedge with one Se(8)Ba4Si square pyramid,  an edgeedge with one Se(9)Ba4Si square pyramid, and  an edgeedge with one Se(7)Ba2SiSb trigonal pyramid. The corner-sharing octahedral tilt angles range from 91-111°. In the sixth Se site, Se(8) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Si(1) atom to form distorted SeBa4Si square pyramids that share corners with four equivalent Se(3)Ba4SbSe octahedra, corners with two equivalent Se(4)Ba4Sb square pyramids, corners with two equivalent Se(6)Ba4Sb square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with two equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(4)Ba4Sb square pyramid,  an edgeedge with one Se(6)Ba4Sb square pyramid,  an edgeedge with one Se(9)Ba4Si square pyramid, edges with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, edges with two equivalent Se(1)Ba4Se trigonal bipyramids, edges with two equivalent Se(7)Ba2SiSb trigonal pyramids, and  a faceface with one Se(9)Ba4Si square pyramid. The corner-sharing octahedral tilt angles range from 41-51°. In the seventh Se site, Se(9) is bonded to four equivalent Ba(2) and one Si(1) atom to form distorted SeBa4Si square pyramids that share corners with four equivalent Se(3)Ba4SbSe octahedra, corners with four equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with four equivalent Se(1)Ba4Se trigonal bipyramids, corners with two equivalent Se(7)Ba2SiSb trigonal pyramids, edges with two equivalent Se(3)Ba4SbSe octahedra,  an edgeedge with one Se(8)Ba4Si square pyramid, edges with two equivalent Se(9)Ba4Si square pyramids, edges with two equivalent Se(7)Ba2SiSb trigonal pyramids, and  a faceface with one Se(8)Ba4Si square pyramid. The corner-sharing octahedral tilt angles range from 25-46°. In the eighth Se site, Se(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Se(2) atom to form distorted SeBa4Se trigonal bipyramids that share corners with two equivalent Se(4)Ba4Sb square pyramids, corners with two equivalent Se(6)Ba4Sb square pyramids, corners with four equivalent Se(9)Ba4Si square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with four equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(3)Ba4SbSe octahedra,  an edgeedge with one Se(4)Ba4Sb square pyramid,  an edgeedge with one Se(6)Ba4Sb square pyramid, edges with two equivalent Se(8)Ba4Si square pyramids, edges with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, and  a faceface with one Se(3)Ba4SbSe octahedra. In the ninth Se site, Se(2) is bonded in a 4-coordinate geometry to two equivalent Ba(2), one Se(1), and one Se(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba4SiSb2Se11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.870
_cell_length_b   13.870
_cell_length_c   8.927
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   139.682
_symmetry_Int_Tables_number   1
_cell_volume   1111.122
_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
  Ba  Ba0  1  0.963  0.543  0.999  1.0
  Ba  Ba1  1  0.457  0.037  0.999  1.0
  Ba  Ba2  1  0.037  0.457  0.499  1.0
  Ba  Ba3  1  0.543  0.963  0.499  1.0
  Ba  Ba4  1  0.787  0.707  0.239  1.0
  Ba  Ba5  1  0.293  0.213  0.239  1.0
  Ba  Ba6  1  0.213  0.293  0.739  1.0
  Ba  Ba7  1  0.707  0.787  0.739  1.0
  Si  Si8  1  0.920  0.080  0.407  1.0
  Si  Si9  1  0.080  0.920  0.907  1.0
  Sb  Sb10  1  0.351  0.649  0.069  1.0
  Sb  Sb11  1  0.649  0.351  0.569  1.0
  Sb  Sb12  1  0.856  0.144  0.070  1.0
  Sb  Sb13  1  0.144  0.856  0.570  1.0
  Se  Se14  1  0.617  0.383  0.095  1.0
  Se  Se15  1  0.383  0.617  0.595  1.0
  Se  Se16  1  0.556  0.444  0.893  1.0
  Se  Se17  1  0.444  0.556  0.393  1.0
  Se  Se18  1  0.527  0.473  0.522  1.0
  Se  Se19  1  0.473  0.527  0.022  1.0
  Se  Se20  1  0.733  0.267  0.726  1.0
  Se  Se21  1  0.267  0.733  0.226  1.0
  Se  Se22  1  0.881  0.552  0.395  1.0
  Se  Se23  1  0.448  0.119  0.395  1.0
  Se  Se24  1  0.119  0.448  0.895  1.0
  Se  Se25  1  0.552  0.881  0.895  1.0
  Se  Se26  1  0.769  0.231  0.208  1.0
  Se  Se27  1  0.231  0.769  0.708  1.0
  Se  Se28  1  0.909  0.711  0.760  1.0
  Se  Se29  1  0.289  0.091  0.760  1.0
  Se  Se30  1  0.091  0.289  0.260  1.0
  Se  Se31  1  0.711  0.909  0.260  1.0
  Se  Se32  1  0.875  0.125  0.625  1.0
  Se  Se33  1  0.125  0.875  0.125  1.0
  Se  Se34  1  0.005  0.995  0.482  1.0
  Se  Se35  1  0.995  0.005  0.982  1.0
[/CIF]
.
The material structure described by Ba4SiSb2Se11 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one Se(1), one Se(7), one Se(8), two equivalent Se(4), two equivalent Se(5), and two equivalent Se(6) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one Se(1), one Se(2), one Se(5), one Se(7), one Se(8), two equivalent Se(3), and two equivalent Se(9) atoms. Si(1) is bonded to one Se(8), one Se(9), and two equivalent Se(7) atoms to form SiSe4 tetrahedra that share  an edgeedge with one Sb(2)Se5 square pyramid. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a distorted see-saw-like geometry to one Se(3), one Se(4), and two equivalent Se(5) atoms. In the second Sb site, Sb(2) is bonded to one Se(6), two equivalent Se(5), and two equivalent Se(7) atoms to form distorted SbSe5 square pyramids that share  an edgeedge with one Si(1)Se4 tetrahedra. There are nine inequivalent Se sites. In the first Se site, Se(3) is bonded to four equivalent Ba(2), one Sb(1), and one Se(2) atom to form distorted SeBa4SbSe octahedra that share  a cornercorner with one Se(4)Ba4Sb square pyramid, corners with four equivalent Se(8)Ba4Si square pyramids, corners with four equivalent Se(9)Ba4Si square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with four equivalent Se(7)Ba2SiSb trigonal pyramids, edges with two equivalent Se(3)Ba4SbSe octahedra, edges with two equivalent Se(9)Ba4Si square pyramids,  an edgeedge with one Se(1)Ba4Se trigonal bipyramid, edges with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, and  a faceface with one Se(1)Ba4Se trigonal bipyramid. In the second Se site, Se(4) is bonded to four equivalent Ba(1) and one Sb(1) atom to form SeBa4Sb square pyramids that share  a cornercorner with one Se(3)Ba4SbSe octahedra, corners with two equivalent Se(8)Ba4Si square pyramids, corners with four equivalent Se(4)Ba4Sb square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with two equivalent Se(1)Ba4Se trigonal bipyramids, corners with four equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(8)Ba4Si square pyramid, edges with four equivalent Se(6)Ba4Sb square pyramids,  an edgeedge with one Se(1)Ba4Se trigonal bipyramid, and edges with four equivalent Se(5)Ba3Sb2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 25°. In the third Se site, Se(5) is bonded to one Ba(2), two equivalent Ba(1), one Sb(1), and one Sb(2) atom to form distorted SeBa3Sb2 trigonal bipyramids that share  a cornercorner with one Se(3)Ba4SbSe octahedra,  a cornercorner with one Se(4)Ba4Sb square pyramid,  a cornercorner with one Se(6)Ba4Sb square pyramid,  a cornercorner with one Se(8)Ba4Si square pyramid, corners with two equivalent Se(9)Ba4Si square pyramids,  a cornercorner with one Se(1)Ba4Se trigonal bipyramid, corners with four equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with five equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(3)Ba4SbSe octahedra,  an edgeedge with one Se(8)Ba4Si square pyramid, edges with two equivalent Se(4)Ba4Sb square pyramids, edges with two equivalent Se(6)Ba4Sb square pyramids, and  an edgeedge with one Se(1)Ba4Se trigonal bipyramid. The corner-sharing octahedral tilt angles are 52°. In the fourth Se site, Se(6) is bonded to four equivalent Ba(1) and one Sb(2) atom to form distorted SeBa4Sb square pyramids that share corners with two equivalent Se(8)Ba4Si square pyramids, corners with four equivalent Se(6)Ba4Sb square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with two equivalent Se(1)Ba4Se trigonal bipyramids, corners with two equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(8)Ba4Si square pyramid, edges with four equivalent Se(4)Ba4Sb square pyramids,  an edgeedge with one Se(1)Ba4Se trigonal bipyramid, edges with four equivalent Se(5)Ba3Sb2 trigonal bipyramids, and edges with two equivalent Se(7)Ba2SiSb trigonal pyramids. In the fifth Se site, Se(7) is bonded to one Ba(1), one Ba(2), one Si(1), and one Sb(2) atom to form distorted SeBa2SiSb trigonal pyramids that share corners with two equivalent Se(3)Ba4SbSe octahedra,  a cornercorner with one Se(6)Ba4Sb square pyramid,  a cornercorner with one Se(8)Ba4Si square pyramid,  a cornercorner with one Se(9)Ba4Si square pyramid, corners with two equivalent Se(4)Ba4Sb square pyramids, corners with two equivalent Se(1)Ba4Se trigonal bipyramids, corners with five equivalent Se(5)Ba3Sb2 trigonal bipyramids,  an edgeedge with one Se(6)Ba4Sb square pyramid,  an edgeedge with one Se(8)Ba4Si square pyramid,  an edgeedge with one Se(9)Ba4Si square pyramid, and  an edgeedge with one Se(7)Ba2SiSb trigonal pyramid. The corner-sharing octahedral tilt angles range from 91-111°. In the sixth Se site, Se(8) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Si(1) atom to form distorted SeBa4Si square pyramids that share corners with four equivalent Se(3)Ba4SbSe octahedra, corners with two equivalent Se(4)Ba4Sb square pyramids, corners with two equivalent Se(6)Ba4Sb square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with two equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(4)Ba4Sb square pyramid,  an edgeedge with one Se(6)Ba4Sb square pyramid,  an edgeedge with one Se(9)Ba4Si square pyramid, edges with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, edges with two equivalent Se(1)Ba4Se trigonal bipyramids, edges with two equivalent Se(7)Ba2SiSb trigonal pyramids, and  a faceface with one Se(9)Ba4Si square pyramid. The corner-sharing octahedral tilt angles range from 41-51°. In the seventh Se site, Se(9) is bonded to four equivalent Ba(2) and one Si(1) atom to form distorted SeBa4Si square pyramids that share corners with four equivalent Se(3)Ba4SbSe octahedra, corners with four equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with four equivalent Se(1)Ba4Se trigonal bipyramids, corners with two equivalent Se(7)Ba2SiSb trigonal pyramids, edges with two equivalent Se(3)Ba4SbSe octahedra,  an edgeedge with one Se(8)Ba4Si square pyramid, edges with two equivalent Se(9)Ba4Si square pyramids, edges with two equivalent Se(7)Ba2SiSb trigonal pyramids, and  a faceface with one Se(8)Ba4Si square pyramid. The corner-sharing octahedral tilt angles range from 25-46°. In the eighth Se site, Se(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and one Se(2) atom to form distorted SeBa4Se trigonal bipyramids that share corners with two equivalent Se(4)Ba4Sb square pyramids, corners with two equivalent Se(6)Ba4Sb square pyramids, corners with four equivalent Se(9)Ba4Si square pyramids, corners with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, corners with four equivalent Se(7)Ba2SiSb trigonal pyramids,  an edgeedge with one Se(3)Ba4SbSe octahedra,  an edgeedge with one Se(4)Ba4Sb square pyramid,  an edgeedge with one Se(6)Ba4Sb square pyramid, edges with two equivalent Se(8)Ba4Si square pyramids, edges with two equivalent Se(5)Ba3Sb2 trigonal bipyramids, and  a faceface with one Se(3)Ba4SbSe octahedra. In the ninth Se site, Se(2) is bonded in a 4-coordinate geometry to two equivalent Ba(2), one Se(1), and one Se(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba4SiSb2Se11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.870
_cell_length_b   13.870
_cell_length_c   8.927
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   139.682
_symmetry_Int_Tables_number   1
_cell_volume   1111.122
_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
  Ba  Ba0  1  0.963  0.543  0.999  1.0
  Ba  Ba1  1  0.457  0.037  0.999  1.0
  Ba  Ba2  1  0.037  0.457  0.499  1.0
  Ba  Ba3  1  0.543  0.963  0.499  1.0
  Ba  Ba4  1  0.787  0.707  0.239  1.0
  Ba  Ba5  1  0.293  0.213  0.239  1.0
  Ba  Ba6  1  0.213  0.293  0.739  1.0
  Ba  Ba7  1  0.707  0.787  0.739  1.0
  Si  Si8  1  0.920  0.080  0.407  1.0
  Si  Si9  1  0.080  0.920  0.907  1.0
  Sb  Sb10  1  0.351  0.649  0.069  1.0
  Sb  Sb11  1  0.649  0.351  0.569  1.0
  Sb  Sb12  1  0.856  0.144  0.070  1.0
  Sb  Sb13  1  0.144  0.856  0.570  1.0
  Se  Se14  1  0.617  0.383  0.095  1.0
  Se  Se15  1  0.383  0.617  0.595  1.0
  Se  Se16  1  0.556  0.444  0.893  1.0
  Se  Se17  1  0.444  0.556  0.393  1.0
  Se  Se18  1  0.527  0.473  0.522  1.0
  Se  Se19  1  0.473  0.527  0.022  1.0
  Se  Se20  1  0.733  0.267  0.726  1.0
  Se  Se21  1  0.267  0.733  0.226  1.0
  Se  Se22  1  0.881  0.552  0.395  1.0
  Se  Se23  1  0.448  0.119  0.395  1.0
  Se  Se24  1  0.119  0.448  0.895  1.0
  Se  Se25  1  0.552  0.881  0.895  1.0
  Se  Se26  1  0.769  0.231  0.208  1.0
  Se  Se27  1  0.231  0.769  0.708  1.0
  Se  Se28  1  0.909  0.711  0.760  1.0
  Se  Se29  1  0.289  0.091  0.760  1.0
  Se  Se30  1  0.091  0.289  0.260  1.0
  Se  Se31  1  0.711  0.909  0.260  1.0
  Se  Se32  1  0.875  0.125  0.625  1.0
  Se  Se33  1  0.125  0.875  0.125  1.0
  Se  Se34  1  0.005  0.995  0.482  1.0
  Se  Se35  1  0.995  0.005  0.982  1.0
[/CIF]
.