The compound described by ErCe3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded to four equivalent Ce(2) and eight equivalent Ce(1) atoms to form ErCe12 cuboctahedra that share corners with four equivalent Er(1)Ce12 cuboctahedra, corners with eight equivalent Ce(2)Ce8Er4 cuboctahedra, edges with eight equivalent Er(1)Ce12 cuboctahedra, edges with sixteen equivalent Ce(1)Ce8Er4 cuboctahedra, faces with four equivalent Er(1)Ce12 cuboctahedra, faces with six equivalent Ce(2)Ce8Er4 cuboctahedra, and faces with eight equivalent Ce(1)Ce8Er4 cuboctahedra. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to four equivalent Er(1), four equivalent Ce(1), and four equivalent Ce(2) atoms to form CeCe8Er4 cuboctahedra that share corners with twelve equivalent Ce(1)Ce8Er4 cuboctahedra, edges with eight equivalent Er(1)Ce12 cuboctahedra, edges with eight equivalent Ce(1)Ce8Er4 cuboctahedra, edges with eight equivalent Ce(2)Ce8Er4 cuboctahedra, faces with four equivalent Er(1)Ce12 cuboctahedra, faces with four equivalent Ce(2)Ce8Er4 cuboctahedra, and faces with ten equivalent Ce(1)Ce8Er4 cuboctahedra. In the second Ce site, Ce(2) is bonded to four equivalent Er(1) and eight equivalent Ce(1) atoms to form CeCe8Er4 cuboctahedra that share corners with four equivalent Ce(2)Ce8Er4 cuboctahedra, corners with eight equivalent Er(1)Ce12 cuboctahedra, edges with eight equivalent Ce(2)Ce8Er4 cuboctahedra, edges with sixteen equivalent Ce(1)Ce8Er4 cuboctahedra, faces with four equivalent Ce(2)Ce8Er4 cuboctahedra, faces with six equivalent Er(1)Ce12 cuboctahedra, and faces with eight equivalent Ce(1)Ce8Er4 cuboctahedra. is represented by the CIF file [CIF]
data_Ce3Er
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.992
_cell_length_b   5.992
_cell_length_c   5.992
_cell_angle_alpha   132.480
_cell_angle_beta   132.480
_cell_angle_gamma   69.473
_symmetry_Int_Tables_number   1
_cell_volume   114.801
_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
  Ce  Ce0  1  0.250  0.750  0.500  1.0
  Ce  Ce1  1  0.750  0.250  0.500  1.0
  Ce  Ce2  1  0.500  0.500  0.000  1.0
  Er  Er3  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by ErCe3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded to four equivalent Ce(2) and eight equivalent Ce(1) atoms to form ErCe12 cuboctahedra that share corners with four equivalent Er(1)Ce12 cuboctahedra, corners with eight equivalent Ce(2)Ce8Er4 cuboctahedra, edges with eight equivalent Er(1)Ce12 cuboctahedra, edges with sixteen equivalent Ce(1)Ce8Er4 cuboctahedra, faces with four equivalent Er(1)Ce12 cuboctahedra, faces with six equivalent Ce(2)Ce8Er4 cuboctahedra, and faces with eight equivalent Ce(1)Ce8Er4 cuboctahedra. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to four equivalent Er(1), four equivalent Ce(1), and four equivalent Ce(2) atoms to form CeCe8Er4 cuboctahedra that share corners with twelve equivalent Ce(1)Ce8Er4 cuboctahedra, edges with eight equivalent Er(1)Ce12 cuboctahedra, edges with eight equivalent Ce(1)Ce8Er4 cuboctahedra, edges with eight equivalent Ce(2)Ce8Er4 cuboctahedra, faces with four equivalent Er(1)Ce12 cuboctahedra, faces with four equivalent Ce(2)Ce8Er4 cuboctahedra, and faces with ten equivalent Ce(1)Ce8Er4 cuboctahedra. In the second Ce site, Ce(2) is bonded to four equivalent Er(1) and eight equivalent Ce(1) atoms to form CeCe8Er4 cuboctahedra that share corners with four equivalent Ce(2)Ce8Er4 cuboctahedra, corners with eight equivalent Er(1)Ce12 cuboctahedra, edges with eight equivalent Ce(2)Ce8Er4 cuboctahedra, edges with sixteen equivalent Ce(1)Ce8Er4 cuboctahedra, faces with four equivalent Ce(2)Ce8Er4 cuboctahedra, faces with six equivalent Er(1)Ce12 cuboctahedra, and faces with eight equivalent Ce(1)Ce8Er4 cuboctahedra. is represented by the CIF file [CIF]
data_Ce3Er
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.992
_cell_length_b   5.992
_cell_length_c   5.992
_cell_angle_alpha   132.480
_cell_angle_beta   132.480
_cell_angle_gamma   69.473
_symmetry_Int_Tables_number   1
_cell_volume   114.801
_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
  Ce  Ce0  1  0.250  0.750  0.500  1.0
  Ce  Ce1  1  0.750  0.250  0.500  1.0
  Ce  Ce2  1  0.500  0.500  0.000  1.0
  Er  Er3  1  0.000  0.000  0.000  1.0
[/CIF]
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