The compound described by Er3Cu4Sn4 crystallizes in the orthorhombic Immm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to two equivalent Sn(1) and four equivalent Sn(2) atoms to form distorted edge-sharing ErSn6 octahedra. In the second Er site, Er(2) is bonded in a 12-coordinate geometry to six equivalent Cu(1), two equivalent Sn(1), and four equivalent Sn(2) atoms. Cu(1) is bonded in a 8-coordinate geometry to three equivalent Er(2), one Cu(1), one Sn(2), and three equivalent Sn(1) atoms. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 9-coordinate geometry to one Er(1), two equivalent Er(2), and six equivalent Cu(1) atoms. In the second Sn site, Sn(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), two equivalent Cu(1), and one Sn(2) atom. is represented by the CIF file [CIF]
data_Er3(CuSn)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.395
_cell_length_b   8.395
_cell_length_c   8.395
_cell_angle_alpha   149.185
_cell_angle_beta   131.218
_cell_angle_gamma   58.818
_symmetry_Int_Tables_number   1
_cell_volume   226.210
_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  0.369  0.869  0.500  1.0
  Er  Er2  1  0.631  0.131  0.500  1.0
  Cu  Cu3  1  0.017  0.328  0.689  1.0
  Cu  Cu4  1  0.639  0.328  0.311  1.0
  Cu  Cu5  1  0.983  0.672  0.311  1.0
  Cu  Cu6  1  0.361  0.672  0.689  1.0
  Sn  Sn7  1  0.216  0.216  0.000  1.0
  Sn  Sn8  1  0.784  0.784  0.000  1.0
  Sn  Sn9  1  0.296  0.500  0.796  1.0
  Sn  Sn10  1  0.704  0.500  0.204  1.0
[/CIF]
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The compound described by Er3Cu4Sn4 crystallizes in the orthorhombic Immm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to two equivalent Sn(1) and four equivalent Sn(2) atoms to form distorted edge-sharing ErSn6 octahedra. In the second Er site, Er(2) is bonded in a 12-coordinate geometry to six equivalent Cu(1), two equivalent Sn(1), and four equivalent Sn(2) atoms. Cu(1) is bonded in a 8-coordinate geometry to three equivalent Er(2), one Cu(1), one Sn(2), and three equivalent Sn(1) atoms. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 9-coordinate geometry to one Er(1), two equivalent Er(2), and six equivalent Cu(1) atoms. In the second Sn site, Sn(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), two equivalent Cu(1), and one Sn(2) atom. is represented by the CIF file [CIF]
data_Er3(CuSn)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.395
_cell_length_b   8.395
_cell_length_c   8.395
_cell_angle_alpha   149.185
_cell_angle_beta   131.218
_cell_angle_gamma   58.818
_symmetry_Int_Tables_number   1
_cell_volume   226.210
_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  0.369  0.869  0.500  1.0
  Er  Er2  1  0.631  0.131  0.500  1.0
  Cu  Cu3  1  0.017  0.328  0.689  1.0
  Cu  Cu4  1  0.639  0.328  0.311  1.0
  Cu  Cu5  1  0.983  0.672  0.311  1.0
  Cu  Cu6  1  0.361  0.672  0.689  1.0
  Sn  Sn7  1  0.216  0.216  0.000  1.0
  Sn  Sn8  1  0.784  0.784  0.000  1.0
  Sn  Sn9  1  0.296  0.500  0.796  1.0
  Sn  Sn10  1  0.704  0.500  0.204  1.0
[/CIF]
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