The material described by Er3Cu4Si4 crystallizes in the orthorhombic Immm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 12-coordinate geometry to six equivalent Cu(1), two equivalent Si(2), and four equivalent Si(1) atoms. In the second Er site, Er(2) is bonded to two equivalent Si(2) and four equivalent Si(1) atoms to form distorted edge-sharing ErSi6 octahedra. Cu(1) is bonded in a 8-coordinate geometry to three equivalent Er(1), one Cu(1), one Si(1), and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Er(2), four equivalent Er(1), two equivalent Cu(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Er(2), two equivalent Er(1), and six equivalent Cu(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er3(CuSi)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.762
_cell_length_b   7.763
_cell_length_c   7.763
_cell_angle_alpha   149.520
_cell_angle_beta   130.641
_cell_angle_gamma   59.124
_symmetry_Int_Tables_number   1
_cell_volume   178.635
_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  0.870  0.870  0.000  1.0
  Er  Er1  1  0.130  0.130  1.000  1.0
  Er  Er2  1  0.500  1.000  0.500  1.0
  Cu  Cu3  1  0.521  0.330  0.191  1.0
  Cu  Cu4  1  0.860  0.669  0.190  1.0
  Cu  Cu5  1  0.140  0.331  0.810  1.0
  Cu  Cu6  1  0.479  0.670  0.809  1.0
  Si  Si7  1  0.815  0.500  0.315  1.0
  Si  Si8  1  0.185  0.500  0.685  1.0
  Si  Si9  1  0.284  0.784  0.500  1.0
  Si  Si10  1  0.716  0.216  0.500  1.0
[/CIF]
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The material described by Er3Cu4Si4 crystallizes in the orthorhombic Immm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 12-coordinate geometry to six equivalent Cu(1), two equivalent Si(2), and four equivalent Si(1) atoms. In the second Er site, Er(2) is bonded to two equivalent Si(2) and four equivalent Si(1) atoms to form distorted edge-sharing ErSi6 octahedra. Cu(1) is bonded in a 8-coordinate geometry to three equivalent Er(1), one Cu(1), one Si(1), and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Er(2), four equivalent Er(1), two equivalent Cu(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Er(2), two equivalent Er(1), and six equivalent Cu(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er3(CuSi)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.762
_cell_length_b   7.763
_cell_length_c   7.763
_cell_angle_alpha   149.520
_cell_angle_beta   130.641
_cell_angle_gamma   59.124
_symmetry_Int_Tables_number   1
_cell_volume   178.635
_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  0.870  0.870  0.000  1.0
  Er  Er1  1  0.130  0.130  1.000  1.0
  Er  Er2  1  0.500  1.000  0.500  1.0
  Cu  Cu3  1  0.521  0.330  0.191  1.0
  Cu  Cu4  1  0.860  0.669  0.190  1.0
  Cu  Cu5  1  0.140  0.331  0.810  1.0
  Cu  Cu6  1  0.479  0.670  0.809  1.0
  Si  Si7  1  0.815  0.500  0.315  1.0
  Si  Si8  1  0.185  0.500  0.685  1.0
  Si  Si9  1  0.284  0.784  0.500  1.0
  Si  Si10  1  0.716  0.216  0.500  1.0
[/CIF]
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