The material described by Er3CuSnS7 crystallizes in the monoclinic P2_1 space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one S(1), one S(2), one S(3), one S(4), one S(7), and two equivalent S(5) atoms. In the second Er site, Er(2) is bonded in a 7-coordinate geometry to one S(1), one S(2), one S(3), one S(5), one S(7), and two equivalent S(6) atoms. In the third Er site, Er(3) is bonded in a 7-coordinate geometry to one S(1), one S(2), one S(3), one S(6), one S(7), and two equivalent S(4) atoms. Cu(1) is bonded in a trigonal planar geometry to one S(1), one S(2), and one S(3) atom. Sn(1) is bonded in a tetrahedral geometry to one S(4), one S(5), one S(6), and one S(7) atom. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(3), and one Cu(1) atom. In the second S site, S(2) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(3), and one Cu(1) atom. In the third S site, S(3) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(3), and one Cu(1) atom. In the fourth S site, S(4) is bonded in a rectangular see-saw-like geometry to one Er(1), two equivalent Er(3), and one Sn(1) atom. In the fifth S site, S(5) is bonded in a rectangular see-saw-like geometry to one Er(2), two equivalent Er(1), and one Sn(1) atom. In the sixth S site, S(6) is bonded in a rectangular see-saw-like geometry to one Er(3), two equivalent Er(2), and one Sn(1) atom. In the seventh S site, S(7) is bonded in a tetrahedral geometry to one Er(1), one Er(2), one Er(3), and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er3CuSnS7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.160
_cell_length_b   9.722
_cell_length_c   9.721
_cell_angle_alpha   119.997
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   504.145
_cell_formula_units_Z   2
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  0.267  0.217  0.359  1.0
  Er  Er1  1  0.267  0.642  0.858  1.0
  Er  Er2  1  0.267  0.142  0.783  1.0
  Er  Er3  1  0.767  0.783  0.641  1.0
  Er  Er4  1  0.767  0.358  0.142  1.0
  Er  Er5  1  0.767  0.858  0.217  1.0
  Cu  Cu6  1  0.168  0.001  0.001  1.0
  Cu  Cu7  1  0.668  0.999  0.999  1.0
  Sn  Sn8  1  0.829  0.333  0.667  1.0
  Sn  Sn9  1  0.329  0.667  0.333  1.0
  S  S10  1  0.693  0.152  0.262  1.0
  S  S11  1  0.693  0.737  0.889  1.0
  S  S12  1  0.693  0.110  0.848  1.0
  S  S13  1  0.193  0.848  0.738  1.0
  S  S14  1  0.193  0.263  0.111  1.0
  S  S15  1  0.193  0.890  0.152  1.0
  S  S16  1  0.016  0.083  0.515  1.0
  S  S17  1  0.016  0.485  0.568  1.0
  S  S18  1  0.016  0.432  0.917  1.0
  S  S19  1  0.516  0.917  0.485  1.0
  S  S20  1  0.516  0.515  0.432  1.0
  S  S21  1  0.516  0.568  0.083  1.0
  S  S22  1  0.441  0.333  0.667  1.0
  S  S23  1  0.941  0.667  0.333  1.0
[/CIF]
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The material described by Er3CuSnS7 crystallizes in the monoclinic P2_1 space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one S(1), one S(2), one S(3), one S(4), one S(7), and two equivalent S(5) atoms. In the second Er site, Er(2) is bonded in a 7-coordinate geometry to one S(1), one S(2), one S(3), one S(5), one S(7), and two equivalent S(6) atoms. In the third Er site, Er(3) is bonded in a 7-coordinate geometry to one S(1), one S(2), one S(3), one S(6), one S(7), and two equivalent S(4) atoms. Cu(1) is bonded in a trigonal planar geometry to one S(1), one S(2), and one S(3) atom. Sn(1) is bonded in a tetrahedral geometry to one S(4), one S(5), one S(6), and one S(7) atom. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(3), and one Cu(1) atom. In the second S site, S(2) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(3), and one Cu(1) atom. In the third S site, S(3) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(3), and one Cu(1) atom. In the fourth S site, S(4) is bonded in a rectangular see-saw-like geometry to one Er(1), two equivalent Er(3), and one Sn(1) atom. In the fifth S site, S(5) is bonded in a rectangular see-saw-like geometry to one Er(2), two equivalent Er(1), and one Sn(1) atom. In the sixth S site, S(6) is bonded in a rectangular see-saw-like geometry to one Er(3), two equivalent Er(2), and one Sn(1) atom. In the seventh S site, S(7) is bonded in a tetrahedral geometry to one Er(1), one Er(2), one Er(3), and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er3CuSnS7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.160
_cell_length_b   9.722
_cell_length_c   9.721
_cell_angle_alpha   119.997
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   504.145
_cell_formula_units_Z   2
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  0.267  0.217  0.359  1.0
  Er  Er1  1  0.267  0.642  0.858  1.0
  Er  Er2  1  0.267  0.142  0.783  1.0
  Er  Er3  1  0.767  0.783  0.641  1.0
  Er  Er4  1  0.767  0.358  0.142  1.0
  Er  Er5  1  0.767  0.858  0.217  1.0
  Cu  Cu6  1  0.168  0.001  0.001  1.0
  Cu  Cu7  1  0.668  0.999  0.999  1.0
  Sn  Sn8  1  0.829  0.333  0.667  1.0
  Sn  Sn9  1  0.329  0.667  0.333  1.0
  S  S10  1  0.693  0.152  0.262  1.0
  S  S11  1  0.693  0.737  0.889  1.0
  S  S12  1  0.693  0.110  0.848  1.0
  S  S13  1  0.193  0.848  0.738  1.0
  S  S14  1  0.193  0.263  0.111  1.0
  S  S15  1  0.193  0.890  0.152  1.0
  S  S16  1  0.016  0.083  0.515  1.0
  S  S17  1  0.016  0.485  0.568  1.0
  S  S18  1  0.016  0.432  0.917  1.0
  S  S19  1  0.516  0.917  0.485  1.0
  S  S20  1  0.516  0.515  0.432  1.0
  S  S21  1  0.516  0.568  0.083  1.0
  S  S22  1  0.441  0.333  0.667  1.0
  S  S23  1  0.941  0.667  0.333  1.0
[/CIF]
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