The crystal structure described by Er3Cu4Sn4 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 6-coordinate geometry to four equivalent Cu(1), two equivalent Sn(1), and four equivalent Sn(2) atoms. In the second Er site, Er(2) is bonded in a 13-coordinate geometry to three equivalent Cu(1), three equivalent Cu(2), three equivalent Sn(1), and four equivalent Sn(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 10-coordinate geometry to two equivalent Er(1), three equivalent Er(2), one Cu(2), one Sn(2), and three equivalent Sn(1) atoms. In the second Cu site, Cu(2) 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), three equivalent Er(2), three equivalent Cu(1), and three equivalent Cu(2) atoms. In the second Sn site, Sn(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one Cu(1), one Cu(2), and one Sn(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er3(CuSn)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.403
_cell_length_b   6.898
_cell_length_c   8.307
_cell_angle_alpha   113.743
_cell_angle_beta   105.367
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   221.023
_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  0.869  0.355  0.738  1.0
  Er  Er2  1  0.131  0.645  0.262  1.0
  Cu  Cu3  1  0.658  0.978  0.316  1.0
  Cu  Cu4  1  0.342  0.022  0.684  1.0
  Cu  Cu5  1  0.684  0.377  0.368  1.0
  Cu  Cu6  1  0.316  0.623  0.632  1.0
  Sn  Sn7  1  0.782  0.801  0.565  1.0
  Sn  Sn8  1  0.218  0.199  0.435  1.0
  Sn  Sn9  1  0.490  0.693  0.979  1.0
  Sn  Sn10  1  0.510  0.307  0.021  1.0
[/CIF]
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The crystal structure described by Er3Cu4Sn4 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 6-coordinate geometry to four equivalent Cu(1), two equivalent Sn(1), and four equivalent Sn(2) atoms. In the second Er site, Er(2) is bonded in a 13-coordinate geometry to three equivalent Cu(1), three equivalent Cu(2), three equivalent Sn(1), and four equivalent Sn(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 10-coordinate geometry to two equivalent Er(1), three equivalent Er(2), one Cu(2), one Sn(2), and three equivalent Sn(1) atoms. In the second Cu site, Cu(2) 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), three equivalent Er(2), three equivalent Cu(1), and three equivalent Cu(2) atoms. In the second Sn site, Sn(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one Cu(1), one Cu(2), and one Sn(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er3(CuSn)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.403
_cell_length_b   6.898
_cell_length_c   8.307
_cell_angle_alpha   113.743
_cell_angle_beta   105.367
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   221.023
_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  0.869  0.355  0.738  1.0
  Er  Er2  1  0.131  0.645  0.262  1.0
  Cu  Cu3  1  0.658  0.978  0.316  1.0
  Cu  Cu4  1  0.342  0.022  0.684  1.0
  Cu  Cu5  1  0.684  0.377  0.368  1.0
  Cu  Cu6  1  0.316  0.623  0.632  1.0
  Sn  Sn7  1  0.782  0.801  0.565  1.0
  Sn  Sn8  1  0.218  0.199  0.435  1.0
  Sn  Sn9  1  0.490  0.693  0.979  1.0
  Sn  Sn10  1  0.510  0.307  0.021  1.0
[/CIF]
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