The material structure described by Er5S7 crystallizes in the monoclinic C2/m space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded to two equivalent S(3) and four equivalent S(2) atoms to form ErS6 octahedra that share corners with two equivalent Er(2)S6 octahedra, corners with four equivalent Er(3)S7 pentagonal bipyramids, edges with two equivalent Er(1)S6 octahedra, and edges with six equivalent Er(3)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 56°. In the second Er site, Er(2) is bonded to one S(3), two equivalent S(1), and three equivalent S(4) atoms to form ErS6 octahedra that share  a cornercorner with one Er(1)S6 octahedra, corners with two equivalent Er(2)S6 octahedra, corners with six equivalent Er(3)S7 pentagonal bipyramids, edges with five equivalent Er(2)S6 octahedra, and  an edgeedge with one Er(3)S7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 0-56°. In the third Er site, Er(3) is bonded to two equivalent S(3), two equivalent S(4), and three equivalent S(2) atoms to form distorted ErS7 pentagonal bipyramids that share corners with two equivalent Er(1)S6 octahedra, corners with six equivalent Er(2)S6 octahedra,  an edgeedge with one Er(2)S6 octahedra, edges with three equivalent Er(1)S6 octahedra, edges with two equivalent Er(3)S7 pentagonal bipyramids, and faces with two equivalent Er(3)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 22-67°. There are four inequivalent S sites. In the first S site, S(1) is bonded in a square co-planar geometry to four equivalent Er(2) atoms. In the second S site, S(2) is bonded to two equivalent Er(1) and three equivalent Er(3) atoms to form distorted SEr5 trigonal bipyramids that share corners with four equivalent S(3)Er4 tetrahedra, corners with two equivalent S(2)Er5 trigonal bipyramids, corners with four equivalent S(4)Er5 trigonal bipyramids, edges with three equivalent S(3)Er4 tetrahedra,  an edgeedge with one S(4)Er5 trigonal bipyramid, and edges with five equivalent S(2)Er5 trigonal bipyramids. In the third S site, S(3) is bonded to one Er(1), one Er(2), and two equivalent Er(3) atoms to form distorted SEr4 tetrahedra that share corners with three equivalent S(3)Er4 tetrahedra, corners with four equivalent S(2)Er5 trigonal bipyramids, corners with five equivalent S(4)Er5 trigonal bipyramids,  an edgeedge with one S(4)Er5 trigonal bipyramid, and edges with three equivalent S(2)Er5 trigonal bipyramids. In the fourth S site, S(4) is bonded to two equivalent Er(3) and three equivalent Er(2) atoms to form SEr5 trigonal bipyramids that share corners with five equivalent S(3)Er4 tetrahedra, corners with four equivalent S(2)Er5 trigonal bipyramids,  an edgeedge with one S(3)Er4 tetrahedra,  an edgeedge with one S(2)Er5 trigonal bipyramid, and edges with four equivalent S(4)Er5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Er5S7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.753
_cell_length_b   6.605
_cell_length_c   11.487
_cell_angle_alpha   103.952
_cell_angle_beta   90.000
_cell_angle_gamma   106.505
_symmetry_Int_Tables_number   1
_cell_volume   264.253
_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  0.000  0.000  0.000  1.0
  Er  Er1  1  0.111  0.223  0.421  1.0
  Er  Er2  1  0.889  0.777  0.579  1.0
  Er  Er3  1  0.300  0.600  0.188  1.0
  Er  Er4  1  0.700  0.400  0.812  1.0
  S  S5  1  0.500  0.000  0.500  1.0
  S  S6  1  0.659  0.318  0.051  1.0
  S  S7  1  0.341  0.682  0.949  1.0
  S  S8  1  0.959  0.918  0.215  1.0
  S  S9  1  0.041  0.082  0.785  1.0
  S  S10  1  0.259  0.518  0.647  1.0
  S  S11  1  0.741  0.482  0.353  1.0
[/CIF]
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The material structure described by Er5S7 crystallizes in the monoclinic C2/m space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded to two equivalent S(3) and four equivalent S(2) atoms to form ErS6 octahedra that share corners with two equivalent Er(2)S6 octahedra, corners with four equivalent Er(3)S7 pentagonal bipyramids, edges with two equivalent Er(1)S6 octahedra, and edges with six equivalent Er(3)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 56°. In the second Er site, Er(2) is bonded to one S(3), two equivalent S(1), and three equivalent S(4) atoms to form ErS6 octahedra that share  a cornercorner with one Er(1)S6 octahedra, corners with two equivalent Er(2)S6 octahedra, corners with six equivalent Er(3)S7 pentagonal bipyramids, edges with five equivalent Er(2)S6 octahedra, and  an edgeedge with one Er(3)S7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 0-56°. In the third Er site, Er(3) is bonded to two equivalent S(3), two equivalent S(4), and three equivalent S(2) atoms to form distorted ErS7 pentagonal bipyramids that share corners with two equivalent Er(1)S6 octahedra, corners with six equivalent Er(2)S6 octahedra,  an edgeedge with one Er(2)S6 octahedra, edges with three equivalent Er(1)S6 octahedra, edges with two equivalent Er(3)S7 pentagonal bipyramids, and faces with two equivalent Er(3)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 22-67°. There are four inequivalent S sites. In the first S site, S(1) is bonded in a square co-planar geometry to four equivalent Er(2) atoms. In the second S site, S(2) is bonded to two equivalent Er(1) and three equivalent Er(3) atoms to form distorted SEr5 trigonal bipyramids that share corners with four equivalent S(3)Er4 tetrahedra, corners with two equivalent S(2)Er5 trigonal bipyramids, corners with four equivalent S(4)Er5 trigonal bipyramids, edges with three equivalent S(3)Er4 tetrahedra,  an edgeedge with one S(4)Er5 trigonal bipyramid, and edges with five equivalent S(2)Er5 trigonal bipyramids. In the third S site, S(3) is bonded to one Er(1), one Er(2), and two equivalent Er(3) atoms to form distorted SEr4 tetrahedra that share corners with three equivalent S(3)Er4 tetrahedra, corners with four equivalent S(2)Er5 trigonal bipyramids, corners with five equivalent S(4)Er5 trigonal bipyramids,  an edgeedge with one S(4)Er5 trigonal bipyramid, and edges with three equivalent S(2)Er5 trigonal bipyramids. In the fourth S site, S(4) is bonded to two equivalent Er(3) and three equivalent Er(2) atoms to form SEr5 trigonal bipyramids that share corners with five equivalent S(3)Er4 tetrahedra, corners with four equivalent S(2)Er5 trigonal bipyramids,  an edgeedge with one S(3)Er4 tetrahedra,  an edgeedge with one S(2)Er5 trigonal bipyramid, and edges with four equivalent S(4)Er5 trigonal bipyramids. is represented by the CIF file [CIF]
data_Er5S7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.753
_cell_length_b   6.605
_cell_length_c   11.487
_cell_angle_alpha   103.952
_cell_angle_beta   90.000
_cell_angle_gamma   106.505
_symmetry_Int_Tables_number   1
_cell_volume   264.253
_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  0.000  0.000  0.000  1.0
  Er  Er1  1  0.111  0.223  0.421  1.0
  Er  Er2  1  0.889  0.777  0.579  1.0
  Er  Er3  1  0.300  0.600  0.188  1.0
  Er  Er4  1  0.700  0.400  0.812  1.0
  S  S5  1  0.500  0.000  0.500  1.0
  S  S6  1  0.659  0.318  0.051  1.0
  S  S7  1  0.341  0.682  0.949  1.0
  S  S8  1  0.959  0.918  0.215  1.0
  S  S9  1  0.041  0.082  0.785  1.0
  S  S10  1  0.259  0.518  0.647  1.0
  S  S11  1  0.741  0.482  0.353  1.0
[/CIF]
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