The compound described by Yb(ErS2)2 crystallizes in the orthorhombic Pnma space group. Yb(1) is bonded to two equivalent S(2), two equivalent S(4), and three equivalent S(1) atoms to form distorted YbS7 pentagonal bipyramids that share corners with four equivalent Er(1)S6 octahedra, corners with four equivalent Er(2)S6 octahedra,  an edgeedge with one Er(1)S6 octahedra, edges with four equivalent Er(2)S6 octahedra, edges with two equivalent Yb(1)S7 pentagonal bipyramids, and faces with two equivalent Yb(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 13-67°. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to one S(2), two equivalent S(4), and three equivalent S(3) atoms to form ErS6 octahedra that share corners with three equivalent Er(2)S6 octahedra, corners with four equivalent Yb(1)S7 pentagonal bipyramids, edges with two equivalent Er(2)S6 octahedra, edges with four equivalent Er(1)S6 octahedra, and  an edgeedge with one Yb(1)S7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 51-60°. In the second Er site, Er(2) is bonded to one S(3), one S(4), two equivalent S(1), and two equivalent S(2) atoms to form ErS6 octahedra that share corners with three equivalent Er(1)S6 octahedra, corners with four equivalent Yb(1)S7 pentagonal bipyramids, edges with two equivalent Er(1)S6 octahedra, edges with two equivalent Er(2)S6 octahedra, and edges with four equivalent Yb(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 51-60°. There are four inequivalent S sites. In the first S site, S(1) is bonded to three equivalent Yb(1) and two equivalent Er(2) atoms to form SYb3Er2 square pyramids that share corners with two equivalent S(4)Yb2Er3 square pyramids, corners with six equivalent S(2)Yb2Er3 trigonal bipyramids, edges with three equivalent S(4)Yb2Er3 square pyramids, edges with four equivalent S(1)Yb3Er2 square pyramids, and edges with two equivalent S(2)Yb2Er3 trigonal bipyramids. In the second S site, S(2) is bonded to two equivalent Yb(1), one Er(1), and two equivalent Er(2) atoms to form distorted SYb2Er3 trigonal bipyramids that share corners with two equivalent S(4)Yb2Er3 square pyramids, corners with six equivalent S(1)Yb3Er2 square pyramids, edges with two equivalent S(1)Yb3Er2 square pyramids, edges with three equivalent S(4)Yb2Er3 square pyramids, and edges with two equivalent S(2)Yb2Er3 trigonal bipyramids. In the third S site, S(3) is bonded in a rectangular see-saw-like geometry to one Er(2) and three equivalent Er(1) atoms. In the fourth S site, S(4) is bonded to two equivalent Yb(1), one Er(2), and two equivalent Er(1) atoms to form SYb2Er3 square pyramids that share corners with two equivalent S(1)Yb3Er2 square pyramids, corners with two equivalent S(2)Yb2Er3 trigonal bipyramids, edges with two equivalent S(4)Yb2Er3 square pyramids, edges with three equivalent S(1)Yb3Er2 square pyramids, and edges with three equivalent S(2)Yb2Er3 trigonal bipyramids. is represented by the CIF card [CIF]
data_Yb(ErS2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.836
_cell_length_b   12.791
_cell_length_c   12.962
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   635.966
_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
  Yb  Yb0  1  0.750  0.869  0.417  1.0
  Yb  Yb1  1  0.250  0.631  0.917  1.0
  Yb  Yb2  1  0.750  0.369  0.083  1.0
  Yb  Yb3  1  0.250  0.131  0.583  1.0
  Er  Er4  1  0.750  0.608  0.584  1.0
  Er  Er5  1  0.250  0.892  0.084  1.0
  Er  Er6  1  0.750  0.108  0.916  1.0
  Er  Er7  1  0.250  0.392  0.416  1.0
  Er  Er8  1  0.750  0.646  0.202  1.0
  Er  Er9  1  0.250  0.854  0.702  1.0
  Er  Er10  1  0.750  0.146  0.298  1.0
  Er  Er11  1  0.250  0.354  0.798  1.0
  S  S12  1  0.750  0.971  0.616  1.0
  S  S13  1  0.250  0.529  0.116  1.0
  S  S14  1  0.750  0.471  0.884  1.0
  S  S15  1  0.250  0.029  0.384  1.0
  S  S16  1  0.750  0.717  0.764  1.0
  S  S17  1  0.250  0.783  0.264  1.0
  S  S18  1  0.750  0.217  0.736  1.0
  S  S19  1  0.250  0.283  0.236  1.0
  S  S20  1  0.750  0.534  0.382  1.0
  S  S21  1  0.250  0.966  0.882  1.0
  S  S22  1  0.750  0.034  0.118  1.0
  S  S23  1  0.250  0.466  0.618  1.0
  S  S24  1  0.750  0.756  0.025  1.0
  S  S25  1  0.250  0.744  0.525  1.0
  S  S26  1  0.750  0.256  0.475  1.0
  S  S27  1  0.250  0.244  0.975  1.0
[/CIF]
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The compound described by Yb(ErS2)2 crystallizes in the orthorhombic Pnma space group. Yb(1) is bonded to two equivalent S(2), two equivalent S(4), and three equivalent S(1) atoms to form distorted YbS7 pentagonal bipyramids that share corners with four equivalent Er(1)S6 octahedra, corners with four equivalent Er(2)S6 octahedra,  an edgeedge with one Er(1)S6 octahedra, edges with four equivalent Er(2)S6 octahedra, edges with two equivalent Yb(1)S7 pentagonal bipyramids, and faces with two equivalent Yb(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 13-67°. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to one S(2), two equivalent S(4), and three equivalent S(3) atoms to form ErS6 octahedra that share corners with three equivalent Er(2)S6 octahedra, corners with four equivalent Yb(1)S7 pentagonal bipyramids, edges with two equivalent Er(2)S6 octahedra, edges with four equivalent Er(1)S6 octahedra, and  an edgeedge with one Yb(1)S7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 51-60°. In the second Er site, Er(2) is bonded to one S(3), one S(4), two equivalent S(1), and two equivalent S(2) atoms to form ErS6 octahedra that share corners with three equivalent Er(1)S6 octahedra, corners with four equivalent Yb(1)S7 pentagonal bipyramids, edges with two equivalent Er(1)S6 octahedra, edges with two equivalent Er(2)S6 octahedra, and edges with four equivalent Yb(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 51-60°. There are four inequivalent S sites. In the first S site, S(1) is bonded to three equivalent Yb(1) and two equivalent Er(2) atoms to form SYb3Er2 square pyramids that share corners with two equivalent S(4)Yb2Er3 square pyramids, corners with six equivalent S(2)Yb2Er3 trigonal bipyramids, edges with three equivalent S(4)Yb2Er3 square pyramids, edges with four equivalent S(1)Yb3Er2 square pyramids, and edges with two equivalent S(2)Yb2Er3 trigonal bipyramids. In the second S site, S(2) is bonded to two equivalent Yb(1), one Er(1), and two equivalent Er(2) atoms to form distorted SYb2Er3 trigonal bipyramids that share corners with two equivalent S(4)Yb2Er3 square pyramids, corners with six equivalent S(1)Yb3Er2 square pyramids, edges with two equivalent S(1)Yb3Er2 square pyramids, edges with three equivalent S(4)Yb2Er3 square pyramids, and edges with two equivalent S(2)Yb2Er3 trigonal bipyramids. In the third S site, S(3) is bonded in a rectangular see-saw-like geometry to one Er(2) and three equivalent Er(1) atoms. In the fourth S site, S(4) is bonded to two equivalent Yb(1), one Er(2), and two equivalent Er(1) atoms to form SYb2Er3 square pyramids that share corners with two equivalent S(1)Yb3Er2 square pyramids, corners with two equivalent S(2)Yb2Er3 trigonal bipyramids, edges with two equivalent S(4)Yb2Er3 square pyramids, edges with three equivalent S(1)Yb3Er2 square pyramids, and edges with three equivalent S(2)Yb2Er3 trigonal bipyramids. is represented by the CIF card [CIF]
data_Yb(ErS2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.836
_cell_length_b   12.791
_cell_length_c   12.962
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   635.966
_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
  Yb  Yb0  1  0.750  0.869  0.417  1.0
  Yb  Yb1  1  0.250  0.631  0.917  1.0
  Yb  Yb2  1  0.750  0.369  0.083  1.0
  Yb  Yb3  1  0.250  0.131  0.583  1.0
  Er  Er4  1  0.750  0.608  0.584  1.0
  Er  Er5  1  0.250  0.892  0.084  1.0
  Er  Er6  1  0.750  0.108  0.916  1.0
  Er  Er7  1  0.250  0.392  0.416  1.0
  Er  Er8  1  0.750  0.646  0.202  1.0
  Er  Er9  1  0.250  0.854  0.702  1.0
  Er  Er10  1  0.750  0.146  0.298  1.0
  Er  Er11  1  0.250  0.354  0.798  1.0
  S  S12  1  0.750  0.971  0.616  1.0
  S  S13  1  0.250  0.529  0.116  1.0
  S  S14  1  0.750  0.471  0.884  1.0
  S  S15  1  0.250  0.029  0.384  1.0
  S  S16  1  0.750  0.717  0.764  1.0
  S  S17  1  0.250  0.783  0.264  1.0
  S  S18  1  0.750  0.217  0.736  1.0
  S  S19  1  0.250  0.283  0.236  1.0
  S  S20  1  0.750  0.534  0.382  1.0
  S  S21  1  0.250  0.966  0.882  1.0
  S  S22  1  0.750  0.034  0.118  1.0
  S  S23  1  0.250  0.466  0.618  1.0
  S  S24  1  0.750  0.756  0.025  1.0
  S  S25  1  0.250  0.744  0.525  1.0
  S  S26  1  0.750  0.256  0.475  1.0
  S  S27  1  0.250  0.244  0.975  1.0
[/CIF]
.