The material described by Er2S2O crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to two equivalent S(2), four equivalent S(1), and one O(1) atom. In the second Er site, Er(2) is bonded in a 3-coordinate geometry to one S(1), three equivalent S(2), and three equivalent O(1) atoms. There are two inequivalent S sites. In the first S site, S(1) is bonded to one Er(2) and four equivalent Er(1) atoms to form distorted SEr5 trigonal bipyramids that share corners with three equivalent O(1)Er4 tetrahedra, corners with four equivalent S(1)Er5 trigonal bipyramids, edges with two equivalent O(1)Er4 tetrahedra, and edges with four equivalent S(1)Er5 trigonal bipyramids. In the second S site, S(2) is bonded in a 5-coordinate geometry to two equivalent Er(1) and three equivalent Er(2) atoms. O(1) is bonded to one Er(1) and three equivalent Er(2) atoms to form OEr4 tetrahedra that share corners with four equivalent O(1)Er4 tetrahedra, corners with three equivalent S(1)Er5 trigonal bipyramids,  an edgeedge with one O(1)Er4 tetrahedra, and edges with two equivalent S(1)Er5 trigonal bipyramids. is represented by the CIF card [CIF]
data_Er2S2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.797
_cell_length_b   6.788
_cell_length_c   8.183
_cell_angle_alpha   80.454
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   372.332
_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
  Er  Er0  1  0.053  0.250  0.861  1.0
  Er  Er1  1  0.553  0.250  0.139  1.0
  Er  Er2  1  0.947  0.750  0.139  1.0
  Er  Er3  1  0.447  0.750  0.861  1.0
  Er  Er4  1  0.145  0.324  0.425  1.0
  Er  Er5  1  0.645  0.176  0.575  1.0
  Er  Er6  1  0.855  0.676  0.575  1.0
  Er  Er7  1  0.355  0.824  0.425  1.0
  S  S8  1  0.777  0.531  0.924  1.0
  S  S9  1  0.277  0.969  0.076  1.0
  S  S10  1  0.223  0.469  0.076  1.0
  S  S11  1  0.723  0.031  0.924  1.0
  S  S12  1  0.868  0.079  0.319  1.0
  S  S13  1  0.368  0.421  0.681  1.0
  S  S14  1  0.132  0.921  0.681  1.0
  S  S15  1  0.632  0.579  0.319  1.0
  O  O16  1  0.587  0.850  0.616  1.0
  O  O17  1  0.087  0.650  0.384  1.0
  O  O18  1  0.413  0.150  0.384  1.0
  O  O19  1  0.913  0.350  0.616  1.0
[/CIF]
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The material described by Er2S2O crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to two equivalent S(2), four equivalent S(1), and one O(1) atom. In the second Er site, Er(2) is bonded in a 3-coordinate geometry to one S(1), three equivalent S(2), and three equivalent O(1) atoms. There are two inequivalent S sites. In the first S site, S(1) is bonded to one Er(2) and four equivalent Er(1) atoms to form distorted SEr5 trigonal bipyramids that share corners with three equivalent O(1)Er4 tetrahedra, corners with four equivalent S(1)Er5 trigonal bipyramids, edges with two equivalent O(1)Er4 tetrahedra, and edges with four equivalent S(1)Er5 trigonal bipyramids. In the second S site, S(2) is bonded in a 5-coordinate geometry to two equivalent Er(1) and three equivalent Er(2) atoms. O(1) is bonded to one Er(1) and three equivalent Er(2) atoms to form OEr4 tetrahedra that share corners with four equivalent O(1)Er4 tetrahedra, corners with three equivalent S(1)Er5 trigonal bipyramids,  an edgeedge with one O(1)Er4 tetrahedra, and edges with two equivalent S(1)Er5 trigonal bipyramids. is represented by the CIF card [CIF]
data_Er2S2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.797
_cell_length_b   6.788
_cell_length_c   8.183
_cell_angle_alpha   80.454
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   372.332
_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
  Er  Er0  1  0.053  0.250  0.861  1.0
  Er  Er1  1  0.553  0.250  0.139  1.0
  Er  Er2  1  0.947  0.750  0.139  1.0
  Er  Er3  1  0.447  0.750  0.861  1.0
  Er  Er4  1  0.145  0.324  0.425  1.0
  Er  Er5  1  0.645  0.176  0.575  1.0
  Er  Er6  1  0.855  0.676  0.575  1.0
  Er  Er7  1  0.355  0.824  0.425  1.0
  S  S8  1  0.777  0.531  0.924  1.0
  S  S9  1  0.277  0.969  0.076  1.0
  S  S10  1  0.223  0.469  0.076  1.0
  S  S11  1  0.723  0.031  0.924  1.0
  S  S12  1  0.868  0.079  0.319  1.0
  S  S13  1  0.368  0.421  0.681  1.0
  S  S14  1  0.132  0.921  0.681  1.0
  S  S15  1  0.632  0.579  0.319  1.0
  O  O16  1  0.587  0.850  0.616  1.0
  O  O17  1  0.087  0.650  0.384  1.0
  O  O18  1  0.413  0.150  0.384  1.0
  O  O19  1  0.913  0.350  0.616  1.0
[/CIF]
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