The material described by Er3Sc2S7 crystallizes in the monoclinic C2/m 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), two equivalent S(3), and three equivalent S(1) atoms. In the second Er site, Er(2) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form ErS6 octahedra that share corners with two equivalent Sc(1)S6 octahedra and edges with two equivalent Er(2)S6 octahedra. The corner-sharing octahedral tilt angles are 52°. Sc(1) is bonded to one S(3), two equivalent S(4), and three equivalent S(2) atoms to form ScS6 octahedra that share  a cornercorner with one Er(2)S6 octahedra, corners with two equivalent Sc(1)S6 octahedra, and edges with five equivalent Sc(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-52°. There are four inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Er(2) and three equivalent Er(1) atoms to form distorted SEr5 trigonal bipyramids that share corners with four equivalent S(3)Er3Sc tetrahedra, corners with two equivalent S(1)Er5 trigonal bipyramids, corners with four equivalent S(2)Er2Sc3 trigonal bipyramids, edges with three equivalent S(3)Er3Sc tetrahedra,  an edgeedge with one S(2)Er2Sc3 trigonal bipyramid, and edges with five equivalent S(1)Er5 trigonal bipyramids. In the second S site, S(2) is bonded to two equivalent Er(1) and three equivalent Sc(1) atoms to form SEr2Sc3 trigonal bipyramids that share corners with five equivalent S(3)Er3Sc tetrahedra, corners with four equivalent S(1)Er5 trigonal bipyramids,  an edgeedge with one S(3)Er3Sc tetrahedra,  an edgeedge with one S(1)Er5 trigonal bipyramid, and edges with four equivalent S(2)Er2Sc3 trigonal bipyramids. In the third S site, S(3) is bonded to one Er(2), two equivalent Er(1), and one Sc(1) atom to form distorted SEr3Sc tetrahedra that share corners with three equivalent S(3)Er3Sc tetrahedra, corners with four equivalent S(1)Er5 trigonal bipyramids, corners with five equivalent S(2)Er2Sc3 trigonal bipyramids,  an edgeedge with one S(2)Er2Sc3 trigonal bipyramid, and edges with three equivalent S(1)Er5 trigonal bipyramids. In the fourth S site, S(4) is bonded in a square co-planar geometry to four equivalent Sc(1) atoms. is represented by the CIF file [CIF]
data_Er3Sc2S7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.701
_cell_length_b   6.448
_cell_length_c   11.302
_cell_angle_alpha   104.220
_cell_angle_beta   89.993
_cell_angle_gamma   73.344
_symmetry_Int_Tables_number   1
_cell_volume   249.769
_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
  Er  Er0  1  0.698  0.605  0.198  1.0
  Er  Er1  1  0.302  0.395  0.802  1.0
  Er  Er2  1  1.000  1.000  0.000  1.0
  Sc  Sc3  1  0.889  0.222  0.428  1.0
  Sc  Sc4  1  0.111  0.778  0.572  1.0
  S  S5  1  0.661  0.678  0.947  1.0
  S  S6  1  0.339  0.322  0.053  1.0
  S  S7  1  0.737  0.525  0.640  1.0
  S  S8  1  0.263  0.475  0.360  1.0
  S  S9  1  0.965  0.070  0.779  1.0
  S  S10  1  0.035  0.930  0.221  1.0
  S  S11  1  0.500  1.000  0.500  1.0
[/CIF]
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The material described by Er3Sc2S7 crystallizes in the monoclinic C2/m 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), two equivalent S(3), and three equivalent S(1) atoms. In the second Er site, Er(2) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form ErS6 octahedra that share corners with two equivalent Sc(1)S6 octahedra and edges with two equivalent Er(2)S6 octahedra. The corner-sharing octahedral tilt angles are 52°. Sc(1) is bonded to one S(3), two equivalent S(4), and three equivalent S(2) atoms to form ScS6 octahedra that share  a cornercorner with one Er(2)S6 octahedra, corners with two equivalent Sc(1)S6 octahedra, and edges with five equivalent Sc(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-52°. There are four inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Er(2) and three equivalent Er(1) atoms to form distorted SEr5 trigonal bipyramids that share corners with four equivalent S(3)Er3Sc tetrahedra, corners with two equivalent S(1)Er5 trigonal bipyramids, corners with four equivalent S(2)Er2Sc3 trigonal bipyramids, edges with three equivalent S(3)Er3Sc tetrahedra,  an edgeedge with one S(2)Er2Sc3 trigonal bipyramid, and edges with five equivalent S(1)Er5 trigonal bipyramids. In the second S site, S(2) is bonded to two equivalent Er(1) and three equivalent Sc(1) atoms to form SEr2Sc3 trigonal bipyramids that share corners with five equivalent S(3)Er3Sc tetrahedra, corners with four equivalent S(1)Er5 trigonal bipyramids,  an edgeedge with one S(3)Er3Sc tetrahedra,  an edgeedge with one S(1)Er5 trigonal bipyramid, and edges with four equivalent S(2)Er2Sc3 trigonal bipyramids. In the third S site, S(3) is bonded to one Er(2), two equivalent Er(1), and one Sc(1) atom to form distorted SEr3Sc tetrahedra that share corners with three equivalent S(3)Er3Sc tetrahedra, corners with four equivalent S(1)Er5 trigonal bipyramids, corners with five equivalent S(2)Er2Sc3 trigonal bipyramids,  an edgeedge with one S(2)Er2Sc3 trigonal bipyramid, and edges with three equivalent S(1)Er5 trigonal bipyramids. In the fourth S site, S(4) is bonded in a square co-planar geometry to four equivalent Sc(1) atoms. is represented by the CIF file [CIF]
data_Er3Sc2S7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.701
_cell_length_b   6.448
_cell_length_c   11.302
_cell_angle_alpha   104.220
_cell_angle_beta   89.993
_cell_angle_gamma   73.344
_symmetry_Int_Tables_number   1
_cell_volume   249.769
_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
  Er  Er0  1  0.698  0.605  0.198  1.0
  Er  Er1  1  0.302  0.395  0.802  1.0
  Er  Er2  1  1.000  1.000  0.000  1.0
  Sc  Sc3  1  0.889  0.222  0.428  1.0
  Sc  Sc4  1  0.111  0.778  0.572  1.0
  S  S5  1  0.661  0.678  0.947  1.0
  S  S6  1  0.339  0.322  0.053  1.0
  S  S7  1  0.737  0.525  0.640  1.0
  S  S8  1  0.263  0.475  0.360  1.0
  S  S9  1  0.965  0.070  0.779  1.0
  S  S10  1  0.035  0.930  0.221  1.0
  S  S11  1  0.500  1.000  0.500  1.0
[/CIF]
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