The material described by Er2Fe3Cu is Cubic Laves-derived structured and crystallizes in the trigonal R-3m space group. Er(1) is bonded in a 12-coordinate geometry to nine equivalent Fe(1) and three equivalent Cu(1) atoms. Fe(1) is bonded to six equivalent Er(1), four equivalent Fe(1), and two equivalent Cu(1) atoms to form FeEr6Fe4Cu2 cuboctahedra that share corners with four equivalent Cu(1)Er6Fe6 cuboctahedra, corners with fourteen equivalent Fe(1)Er6Fe4Cu2 cuboctahedra, edges with six equivalent Fe(1)Er6Fe4Cu2 cuboctahedra, faces with six equivalent Cu(1)Er6Fe6 cuboctahedra, and faces with twelve equivalent Fe(1)Er6Fe4Cu2 cuboctahedra. Cu(1) is bonded to six equivalent Er(1) and six equivalent Fe(1) atoms to form CuEr6Fe6 cuboctahedra that share corners with six equivalent Cu(1)Er6Fe6 cuboctahedra, corners with twelve equivalent Fe(1)Er6Fe4Cu2 cuboctahedra, edges with six equivalent Cu(1)Er6Fe6 cuboctahedra, and faces with eighteen equivalent Fe(1)Er6Fe4Cu2 cuboctahedra. is represented by the CIF card [CIF]
data_Er2Fe3Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.167
_cell_length_b   5.167
_cell_length_c   5.167
_cell_angle_alpha   58.516
_cell_angle_beta   58.516
_cell_angle_gamma   58.516
_symmetry_Int_Tables_number   1
_cell_volume   94.253
_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  0.123  0.123  0.123  1.0
  Er  Er1  1  0.877  0.877  0.877  1.0
  Fe  Fe2  1  0.500  0.000  0.500  1.0
  Fe  Fe3  1  0.000  0.500  0.500  1.0
  Fe  Fe4  1  0.500  0.500  0.000  1.0
  Cu  Cu5  1  0.500  0.500  0.500  1.0
[/CIF]
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The material described by Er2Fe3Cu is Cubic Laves-derived structured and crystallizes in the trigonal R-3m space group. Er(1) is bonded in a 12-coordinate geometry to nine equivalent Fe(1) and three equivalent Cu(1) atoms. Fe(1) is bonded to six equivalent Er(1), four equivalent Fe(1), and two equivalent Cu(1) atoms to form FeEr6Fe4Cu2 cuboctahedra that share corners with four equivalent Cu(1)Er6Fe6 cuboctahedra, corners with fourteen equivalent Fe(1)Er6Fe4Cu2 cuboctahedra, edges with six equivalent Fe(1)Er6Fe4Cu2 cuboctahedra, faces with six equivalent Cu(1)Er6Fe6 cuboctahedra, and faces with twelve equivalent Fe(1)Er6Fe4Cu2 cuboctahedra. Cu(1) is bonded to six equivalent Er(1) and six equivalent Fe(1) atoms to form CuEr6Fe6 cuboctahedra that share corners with six equivalent Cu(1)Er6Fe6 cuboctahedra, corners with twelve equivalent Fe(1)Er6Fe4Cu2 cuboctahedra, edges with six equivalent Cu(1)Er6Fe6 cuboctahedra, and faces with eighteen equivalent Fe(1)Er6Fe4Cu2 cuboctahedra. is represented by the CIF card [CIF]
data_Er2Fe3Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.167
_cell_length_b   5.167
_cell_length_c   5.167
_cell_angle_alpha   58.516
_cell_angle_beta   58.516
_cell_angle_gamma   58.516
_symmetry_Int_Tables_number   1
_cell_volume   94.253
_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  0.123  0.123  0.123  1.0
  Er  Er1  1  0.877  0.877  0.877  1.0
  Fe  Fe2  1  0.500  0.000  0.500  1.0
  Fe  Fe3  1  0.000  0.500  0.500  1.0
  Fe  Fe4  1  0.500  0.500  0.000  1.0
  Cu  Cu5  1  0.500  0.500  0.500  1.0
[/CIF]
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