The material described by Er3Sn7 crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 10-coordinate geometry to two equivalent Er(1), four equivalent Sn(1), and four equivalent Sn(2) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to two equivalent Sn(3) and four equivalent Sn(4) atoms. There are four inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 10-coordinate geometry to four equivalent Er(1), two equivalent Sn(1), and four equivalent Sn(3) atoms. In the second Sn site, Sn(2) is bonded in a 2-coordinate geometry to two equivalent Er(1), two equivalent Sn(4), and four equivalent Sn(3) atoms. In the third Sn site, Sn(3) is bonded in a 10-coordinate geometry to two equivalent Er(2), two equivalent Sn(1), two equivalent Sn(3), and four equivalent Sn(2) atoms. In the fourth Sn site, Sn(4) is bonded in a 10-coordinate geometry to four equivalent Er(2), two equivalent Sn(2), and four equivalent Sn(4) atoms. is represented by the CIF file [CIF]
data_Er3Sn7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.826
_cell_length_b   14.826
_cell_length_c   5.861
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   12.065
_symmetry_Int_Tables_number   1
_cell_volume   269.271
_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  0.500  1.0
  Er  Er1  1  0.697  0.697  0.000  1.0
  Er  Er2  1  0.303  0.303  0.000  1.0
  Sn  Sn3  1  0.500  0.500  0.000  1.0
  Sn  Sn4  1  0.598  0.598  0.500  1.0
  Sn  Sn5  1  0.402  0.402  0.500  1.0
  Sn  Sn6  1  0.900  0.900  0.000  1.0
  Sn  Sn7  1  0.100  0.100  0.000  1.0
  Sn  Sn8  1  0.799  0.799  0.500  1.0
  Sn  Sn9  1  0.201  0.201  0.500  1.0
[/CIF]
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The material described by Er3Sn7 crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 10-coordinate geometry to two equivalent Er(1), four equivalent Sn(1), and four equivalent Sn(2) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to two equivalent Sn(3) and four equivalent Sn(4) atoms. There are four inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 10-coordinate geometry to four equivalent Er(1), two equivalent Sn(1), and four equivalent Sn(3) atoms. In the second Sn site, Sn(2) is bonded in a 2-coordinate geometry to two equivalent Er(1), two equivalent Sn(4), and four equivalent Sn(3) atoms. In the third Sn site, Sn(3) is bonded in a 10-coordinate geometry to two equivalent Er(2), two equivalent Sn(1), two equivalent Sn(3), and four equivalent Sn(2) atoms. In the fourth Sn site, Sn(4) is bonded in a 10-coordinate geometry to four equivalent Er(2), two equivalent Sn(2), and four equivalent Sn(4) atoms. is represented by the CIF file [CIF]
data_Er3Sn7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.826
_cell_length_b   14.826
_cell_length_c   5.861
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   12.065
_symmetry_Int_Tables_number   1
_cell_volume   269.271
_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  0.500  1.0
  Er  Er1  1  0.697  0.697  0.000  1.0
  Er  Er2  1  0.303  0.303  0.000  1.0
  Sn  Sn3  1  0.500  0.500  0.000  1.0
  Sn  Sn4  1  0.598  0.598  0.500  1.0
  Sn  Sn5  1  0.402  0.402  0.500  1.0
  Sn  Sn6  1  0.900  0.900  0.000  1.0
  Sn  Sn7  1  0.100  0.100  0.000  1.0
  Sn  Sn8  1  0.799  0.799  0.500  1.0
  Sn  Sn9  1  0.201  0.201  0.500  1.0
[/CIF]
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