The crystal structure described by Gd4Yb11Se22 crystallizes in the monoclinic C2/m space group. There are six inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to one Se(2), one Se(9), two equivalent Se(8), and three equivalent Se(11) atoms. In the second Yb site, Yb(2) is bonded in a 6-coordinate geometry to one Se(4), one Se(7), two equivalent Se(1), and two equivalent Se(10) atoms. In the third Yb site, Yb(3) is bonded in a 5-coordinate geometry to one Se(3), one Se(6), two equivalent Se(5), and two equivalent Se(9) atoms. In the fourth Yb site, Yb(4) is bonded to one Se(11), two equivalent Se(2), and three equivalent Se(3) atoms to form edge-sharing YbSe6 octahedra. In the fifth Yb site, Yb(5) is bonded to one Se(10), two equivalent Se(4), and two equivalent Se(6) atoms to form distorted YbSe5 trigonal bipyramids that share  a cornercorner with one Yb(6)Se6 octahedra, corners with two equivalent Se(7)Yb3Gd2Se octahedra, and edges with two equivalent Yb(5)Se5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 72-73°. In the sixth Yb site, Yb(6) is bonded to two equivalent Se(10) and four equivalent Se(7) atoms to form YbSe6 octahedra that share corners with two equivalent Yb(5)Se5 trigonal bipyramids and edges with two equivalent Yb(6)Se6 octahedra. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(9), two equivalent Se(6), two equivalent Se(7), and two equivalent Se(8) atoms. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to one Se(4), one Se(8), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(5) atoms. There are eleven inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Yb(2), one Gd(1), and two equivalent Gd(2) atoms to form distorted SeYb2Gd3 trigonal bipyramids that share  a cornercorner with one Se(9)Yb3Gd tetrahedra, corners with two equivalent Se(10)Yb4 tetrahedra, edges with two equivalent Se(7)Yb3Gd2Se octahedra,  an edgeedge with one Se(10)Yb4 tetrahedra, edges with two equivalent Se(1)Yb2Gd3 trigonal bipyramids, and edges with two equivalent Se(8)Yb2Gd3 trigonal bipyramids. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Yb(1), two equivalent Yb(4), two equivalent Gd(2), and one Se(5) atom. In the third Se site, Se(3) is bonded to one Yb(3) and three equivalent Yb(4) atoms to form distorted SeYb4 trigonal pyramids that share corners with two equivalent Se(9)Yb3Gd tetrahedra, corners with three equivalent Se(11)Yb4 tetrahedra, corners with two equivalent Se(3)Yb4 trigonal pyramids, and edges with two equivalent Se(3)Yb4 trigonal pyramids. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to one Yb(2), two equivalent Yb(5), and one Gd(2) atom. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to two equivalent Yb(3), two equivalent Gd(2), and one Se(2) atom. In the sixth Se site, Se(6) is bonded in a 6-coordinate geometry to one Yb(3), two equivalent Yb(5), two equivalent Gd(1), and one Se(7) atom. In the seventh Se site, Se(7) is bonded to one Yb(2), two equivalent Yb(6), two equivalent Gd(1), and one Se(6) atom to form distorted SeYb3Gd2Se octahedra that share corners with two equivalent Se(7)Yb3Gd2Se octahedra, corners with two equivalent Se(9)Yb3Gd tetrahedra, corners with two equivalent Se(10)Yb4 tetrahedra, corners with two equivalent Yb(5)Se5 trigonal bipyramids, corners with two equivalent Se(8)Yb2Gd3 trigonal bipyramids, edges with three equivalent Se(7)Yb3Gd2Se octahedra, edges with two equivalent Se(10)Yb4 tetrahedra,  an edgeedge with one Se(8)Yb2Gd3 trigonal bipyramid, and edges with two equivalent Se(1)Yb2Gd3 trigonal bipyramids. The corner-sharing octahedra are not tilted. In the eighth Se site, Se(8) is bonded to two equivalent Yb(1), one Gd(2), and two equivalent Gd(1) atoms to form distorted SeYb2Gd3 trigonal bipyramids that share corners with two equivalent Se(7)Yb3Gd2Se octahedra, corners with four equivalent Se(11)Yb4 tetrahedra,  an edgeedge with one Se(7)Yb3Gd2Se octahedra,  an edgeedge with one Se(11)Yb4 tetrahedra, edges with two equivalent Se(9)Yb3Gd tetrahedra, edges with two equivalent Se(1)Yb2Gd3 trigonal bipyramids, and edges with two equivalent Se(8)Yb2Gd3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 24°. In the ninth Se site, Se(9) is bonded to one Yb(1), two equivalent Yb(3), and one Gd(1) atom to form distorted SeYb3Gd tetrahedra that share corners with two equivalent Se(7)Yb3Gd2Se octahedra, corners with two equivalent Se(9)Yb3Gd tetrahedra, corners with three equivalent Se(11)Yb4 tetrahedra,  a cornercorner with one Se(1)Yb2Gd3 trigonal bipyramid, corners with two equivalent Se(3)Yb4 trigonal pyramids, and edges with two equivalent Se(8)Yb2Gd3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 56°. In the tenth Se site, Se(10) is bonded to one Yb(5), one Yb(6), and two equivalent Yb(2) atoms to form SeYb4 tetrahedra that share corners with two equivalent Se(7)Yb3Gd2Se octahedra, corners with three equivalent Se(10)Yb4 tetrahedra, corners with two equivalent Se(1)Yb2Gd3 trigonal bipyramids, edges with two equivalent Se(7)Yb3Gd2Se octahedra, and  an edgeedge with one Se(1)Yb2Gd3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 84°. In the eleventh Se site, Se(11) is bonded to one Yb(4) and three equivalent Yb(1) atoms to form SeYb4 tetrahedra that share corners with two equivalent Se(11)Yb4 tetrahedra, corners with three equivalent Se(9)Yb3Gd tetrahedra, corners with four equivalent Se(8)Yb2Gd3 trigonal bipyramids, corners with three equivalent Se(3)Yb4 trigonal pyramids, edges with two equivalent Se(11)Yb4 tetrahedra, and  an edgeedge with one Se(8)Yb2Gd3 trigonal bipyramid. is represented by the CIF file [CIF]
data_Yb11(Gd2Se11)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.199
_cell_length_b   11.735
_cell_length_c   21.597
_cell_angle_alpha   94.345
_cell_angle_beta   95.579
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1056.177
_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
  Yb  Yb0  1  0.801  0.518  0.603  1.0
  Yb  Yb1  1  0.199  0.482  0.397  1.0
  Yb  Yb2  1  0.459  0.800  0.918  1.0
  Yb  Yb3  1  0.541  0.200  0.082  1.0
  Yb  Yb4  1  0.663  0.830  0.326  1.0
  Yb  Yb5  1  0.337  0.170  0.674  1.0
  Yb  Yb6  1  0.267  0.861  0.535  1.0
  Yb  Yb7  1  0.733  0.139  0.465  1.0
  Yb  Yb8  1  0.062  0.829  0.123  1.0
  Yb  Yb9  1  0.938  0.171  0.877  1.0
  Yb  Yb10  1  0.000  0.500  0.000  1.0
  Gd  Gd11  1  0.892  0.502  0.783  1.0
  Gd  Gd12  1  0.108  0.498  0.217  1.0
  Gd  Gd13  1  0.373  0.832  0.746  1.0
  Gd  Gd14  1  0.627  0.168  0.254  1.0
  Se  Se15  1  0.911  0.746  0.822  1.0
  Se  Se16  1  0.089  0.254  0.178  1.0
  Se  Se17  1  0.819  0.834  0.639  1.0
  Se  Se18  1  0.181  0.166  0.361  1.0
  Se  Se19  1  0.725  0.894  0.450  1.0
  Se  Se20  1  0.275  0.106  0.550  1.0
  Se  Se21  1  0.428  0.011  0.857  1.0
  Se  Se22  1  0.572  0.989  0.143  1.0
  Se  Se23  1  0.143  0.001  0.285  1.0
  Se  Se24  1  0.857  0.999  0.715  1.0
  Se  Se25  1  0.586  0.661  0.172  1.0
  Se  Se26  1  0.414  0.339  0.828  1.0
  Se  Se27  1  0.449  0.511  0.899  1.0
  Se  Se28  1  0.551  0.489  0.101  1.0
  Se  Se29  1  0.352  0.586  0.705  1.0
  Se  Se30  1  0.648  0.414  0.295  1.0
  Se  Se31  1  0.160  0.672  0.319  1.0
  Se  Se32  1  0.840  0.328  0.681  1.0
  Se  Se33  1  1.000  0.741  0.999  1.0
  Se  Se34  1  0.000  0.259  0.001  1.0
  Se  Se35  1  0.262  0.609  0.525  1.0
  Se  Se36  1  0.738  0.391  0.475  1.0
[/CIF]
.
The crystal structure described by Gd4Yb11Se22 crystallizes in the monoclinic C2/m space group. There are six inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to one Se(2), one Se(9), two equivalent Se(8), and three equivalent Se(11) atoms. In the second Yb site, Yb(2) is bonded in a 6-coordinate geometry to one Se(4), one Se(7), two equivalent Se(1), and two equivalent Se(10) atoms. In the third Yb site, Yb(3) is bonded in a 5-coordinate geometry to one Se(3), one Se(6), two equivalent Se(5), and two equivalent Se(9) atoms. In the fourth Yb site, Yb(4) is bonded to one Se(11), two equivalent Se(2), and three equivalent Se(3) atoms to form edge-sharing YbSe6 octahedra. In the fifth Yb site, Yb(5) is bonded to one Se(10), two equivalent Se(4), and two equivalent Se(6) atoms to form distorted YbSe5 trigonal bipyramids that share  a cornercorner with one Yb(6)Se6 octahedra, corners with two equivalent Se(7)Yb3Gd2Se octahedra, and edges with two equivalent Yb(5)Se5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 72-73°. In the sixth Yb site, Yb(6) is bonded to two equivalent Se(10) and four equivalent Se(7) atoms to form YbSe6 octahedra that share corners with two equivalent Yb(5)Se5 trigonal bipyramids and edges with two equivalent Yb(6)Se6 octahedra. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(9), two equivalent Se(6), two equivalent Se(7), and two equivalent Se(8) atoms. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to one Se(4), one Se(8), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(5) atoms. There are eleven inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Yb(2), one Gd(1), and two equivalent Gd(2) atoms to form distorted SeYb2Gd3 trigonal bipyramids that share  a cornercorner with one Se(9)Yb3Gd tetrahedra, corners with two equivalent Se(10)Yb4 tetrahedra, edges with two equivalent Se(7)Yb3Gd2Se octahedra,  an edgeedge with one Se(10)Yb4 tetrahedra, edges with two equivalent Se(1)Yb2Gd3 trigonal bipyramids, and edges with two equivalent Se(8)Yb2Gd3 trigonal bipyramids. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Yb(1), two equivalent Yb(4), two equivalent Gd(2), and one Se(5) atom. In the third Se site, Se(3) is bonded to one Yb(3) and three equivalent Yb(4) atoms to form distorted SeYb4 trigonal pyramids that share corners with two equivalent Se(9)Yb3Gd tetrahedra, corners with three equivalent Se(11)Yb4 tetrahedra, corners with two equivalent Se(3)Yb4 trigonal pyramids, and edges with two equivalent Se(3)Yb4 trigonal pyramids. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to one Yb(2), two equivalent Yb(5), and one Gd(2) atom. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to two equivalent Yb(3), two equivalent Gd(2), and one Se(2) atom. In the sixth Se site, Se(6) is bonded in a 6-coordinate geometry to one Yb(3), two equivalent Yb(5), two equivalent Gd(1), and one Se(7) atom. In the seventh Se site, Se(7) is bonded to one Yb(2), two equivalent Yb(6), two equivalent Gd(1), and one Se(6) atom to form distorted SeYb3Gd2Se octahedra that share corners with two equivalent Se(7)Yb3Gd2Se octahedra, corners with two equivalent Se(9)Yb3Gd tetrahedra, corners with two equivalent Se(10)Yb4 tetrahedra, corners with two equivalent Yb(5)Se5 trigonal bipyramids, corners with two equivalent Se(8)Yb2Gd3 trigonal bipyramids, edges with three equivalent Se(7)Yb3Gd2Se octahedra, edges with two equivalent Se(10)Yb4 tetrahedra,  an edgeedge with one Se(8)Yb2Gd3 trigonal bipyramid, and edges with two equivalent Se(1)Yb2Gd3 trigonal bipyramids. The corner-sharing octahedra are not tilted. In the eighth Se site, Se(8) is bonded to two equivalent Yb(1), one Gd(2), and two equivalent Gd(1) atoms to form distorted SeYb2Gd3 trigonal bipyramids that share corners with two equivalent Se(7)Yb3Gd2Se octahedra, corners with four equivalent Se(11)Yb4 tetrahedra,  an edgeedge with one Se(7)Yb3Gd2Se octahedra,  an edgeedge with one Se(11)Yb4 tetrahedra, edges with two equivalent Se(9)Yb3Gd tetrahedra, edges with two equivalent Se(1)Yb2Gd3 trigonal bipyramids, and edges with two equivalent Se(8)Yb2Gd3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 24°. In the ninth Se site, Se(9) is bonded to one Yb(1), two equivalent Yb(3), and one Gd(1) atom to form distorted SeYb3Gd tetrahedra that share corners with two equivalent Se(7)Yb3Gd2Se octahedra, corners with two equivalent Se(9)Yb3Gd tetrahedra, corners with three equivalent Se(11)Yb4 tetrahedra,  a cornercorner with one Se(1)Yb2Gd3 trigonal bipyramid, corners with two equivalent Se(3)Yb4 trigonal pyramids, and edges with two equivalent Se(8)Yb2Gd3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 56°. In the tenth Se site, Se(10) is bonded to one Yb(5), one Yb(6), and two equivalent Yb(2) atoms to form SeYb4 tetrahedra that share corners with two equivalent Se(7)Yb3Gd2Se octahedra, corners with three equivalent Se(10)Yb4 tetrahedra, corners with two equivalent Se(1)Yb2Gd3 trigonal bipyramids, edges with two equivalent Se(7)Yb3Gd2Se octahedra, and  an edgeedge with one Se(1)Yb2Gd3 trigonal bipyramid. The corner-sharing octahedral tilt angles are 84°. In the eleventh Se site, Se(11) is bonded to one Yb(4) and three equivalent Yb(1) atoms to form SeYb4 tetrahedra that share corners with two equivalent Se(11)Yb4 tetrahedra, corners with three equivalent Se(9)Yb3Gd tetrahedra, corners with four equivalent Se(8)Yb2Gd3 trigonal bipyramids, corners with three equivalent Se(3)Yb4 trigonal pyramids, edges with two equivalent Se(11)Yb4 tetrahedra, and  an edgeedge with one Se(8)Yb2Gd3 trigonal bipyramid. is represented by the CIF file [CIF]
data_Yb11(Gd2Se11)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.199
_cell_length_b   11.735
_cell_length_c   21.597
_cell_angle_alpha   94.345
_cell_angle_beta   95.579
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1056.177
_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
  Yb  Yb0  1  0.801  0.518  0.603  1.0
  Yb  Yb1  1  0.199  0.482  0.397  1.0
  Yb  Yb2  1  0.459  0.800  0.918  1.0
  Yb  Yb3  1  0.541  0.200  0.082  1.0
  Yb  Yb4  1  0.663  0.830  0.326  1.0
  Yb  Yb5  1  0.337  0.170  0.674  1.0
  Yb  Yb6  1  0.267  0.861  0.535  1.0
  Yb  Yb7  1  0.733  0.139  0.465  1.0
  Yb  Yb8  1  0.062  0.829  0.123  1.0
  Yb  Yb9  1  0.938  0.171  0.877  1.0
  Yb  Yb10  1  0.000  0.500  0.000  1.0
  Gd  Gd11  1  0.892  0.502  0.783  1.0
  Gd  Gd12  1  0.108  0.498  0.217  1.0
  Gd  Gd13  1  0.373  0.832  0.746  1.0
  Gd  Gd14  1  0.627  0.168  0.254  1.0
  Se  Se15  1  0.911  0.746  0.822  1.0
  Se  Se16  1  0.089  0.254  0.178  1.0
  Se  Se17  1  0.819  0.834  0.639  1.0
  Se  Se18  1  0.181  0.166  0.361  1.0
  Se  Se19  1  0.725  0.894  0.450  1.0
  Se  Se20  1  0.275  0.106  0.550  1.0
  Se  Se21  1  0.428  0.011  0.857  1.0
  Se  Se22  1  0.572  0.989  0.143  1.0
  Se  Se23  1  0.143  0.001  0.285  1.0
  Se  Se24  1  0.857  0.999  0.715  1.0
  Se  Se25  1  0.586  0.661  0.172  1.0
  Se  Se26  1  0.414  0.339  0.828  1.0
  Se  Se27  1  0.449  0.511  0.899  1.0
  Se  Se28  1  0.551  0.489  0.101  1.0
  Se  Se29  1  0.352  0.586  0.705  1.0
  Se  Se30  1  0.648  0.414  0.295  1.0
  Se  Se31  1  0.160  0.672  0.319  1.0
  Se  Se32  1  0.840  0.328  0.681  1.0
  Se  Se33  1  1.000  0.741  0.999  1.0
  Se  Se34  1  0.000  0.259  0.001  1.0
  Se  Se35  1  0.262  0.609  0.525  1.0
  Se  Se36  1  0.738  0.391  0.475  1.0
[/CIF]
.