The crystal structure described by Er2CoAl3 crystallizes in the trigonal R-3m space group. Er(1) is bonded in a 16-coordinate geometry to four equivalent Er(1), three equivalent Co(1), and nine equivalent Al(1) atoms. Co(1) is bonded to six equivalent Er(1) and six equivalent Al(1) atoms to form CoEr6Al6 cuboctahedra that share corners with six equivalent Co(1)Er6Al6 cuboctahedra, corners with twelve equivalent Al(1)Er6Al4Co2 cuboctahedra, edges with six equivalent Co(1)Er6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Er6Al4Co2 cuboctahedra. Al(1) is bonded to six equivalent Er(1), two equivalent Co(1), and four equivalent Al(1) atoms to form distorted AlEr6Al4Co2 cuboctahedra that share corners with four equivalent Co(1)Er6Al6 cuboctahedra, corners with fourteen equivalent Al(1)Er6Al4Co2 cuboctahedra, edges with six equivalent Al(1)Er6Al4Co2 cuboctahedra, faces with six equivalent Co(1)Er6Al6 cuboctahedra, and faces with twelve equivalent Al(1)Er6Al4Co2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2Al3Co
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.308
_cell_length_b   5.308
_cell_length_c   5.308
_cell_angle_alpha   61.661
_cell_angle_beta   61.661
_cell_angle_gamma   61.661
_symmetry_Int_Tables_number   1
_cell_volume   109.715
_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  0.627  0.627  0.627  1.0
  Er  Er1  1  0.373  0.373  0.373  1.0
  Al  Al2  1  0.000  0.500  0.000  1.0
  Al  Al3  1  0.500  0.000  0.000  1.0
  Al  Al4  1  0.000  0.000  0.500  1.0
  Co  Co5  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Er2CoAl3 crystallizes in the trigonal R-3m space group. Er(1) is bonded in a 16-coordinate geometry to four equivalent Er(1), three equivalent Co(1), and nine equivalent Al(1) atoms. Co(1) is bonded to six equivalent Er(1) and six equivalent Al(1) atoms to form CoEr6Al6 cuboctahedra that share corners with six equivalent Co(1)Er6Al6 cuboctahedra, corners with twelve equivalent Al(1)Er6Al4Co2 cuboctahedra, edges with six equivalent Co(1)Er6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Er6Al4Co2 cuboctahedra. Al(1) is bonded to six equivalent Er(1), two equivalent Co(1), and four equivalent Al(1) atoms to form distorted AlEr6Al4Co2 cuboctahedra that share corners with four equivalent Co(1)Er6Al6 cuboctahedra, corners with fourteen equivalent Al(1)Er6Al4Co2 cuboctahedra, edges with six equivalent Al(1)Er6Al4Co2 cuboctahedra, faces with six equivalent Co(1)Er6Al6 cuboctahedra, and faces with twelve equivalent Al(1)Er6Al4Co2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2Al3Co
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.308
_cell_length_b   5.308
_cell_length_c   5.308
_cell_angle_alpha   61.661
_cell_angle_beta   61.661
_cell_angle_gamma   61.661
_symmetry_Int_Tables_number   1
_cell_volume   109.715
_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  0.627  0.627  0.627  1.0
  Er  Er1  1  0.373  0.373  0.373  1.0
  Al  Al2  1  0.000  0.500  0.000  1.0
  Al  Al3  1  0.500  0.000  0.000  1.0
  Al  Al4  1  0.000  0.000  0.500  1.0
  Co  Co5  1  0.000  0.000  0.000  1.0
[/CIF]
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