The compound described by ErCoAl crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 12-coordinate geometry to three equivalent Er(2), one Co(3), two equivalent Co(1), two equivalent Co(2), three equivalent Al(1), and four equivalent Al(2) atoms. In the second Er site, Er(2) is bonded in a 16-coordinate geometry to one Er(2), three equivalent Er(1), one Co(1), two equivalent Co(3), four equivalent Co(2), two equivalent Al(2), and three equivalent Al(1) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Er(2), four equivalent Er(1), two equivalent Al(1), and four equivalent Al(2) atoms to form CoEr6Al6 cuboctahedra that share corners with four equivalent Co(1)Er6Al6 cuboctahedra, corners with four equivalent Al(1)Er6Al2Co4 cuboctahedra, edges with two equivalent Co(1)Er6Al6 cuboctahedra, faces with six equivalent Al(1)Er6Al2Co4 cuboctahedra, and faces with eight equivalent Al(2)Er6Al4Co2 cuboctahedra. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to two equivalent Er(1), four equivalent Er(2), two equivalent Co(2), two equivalent Co(3), and two equivalent Al(1) atoms. In the third Co site, Co(3) is bonded in a 12-coordinate geometry to two equivalent Er(1), four equivalent Er(2), four equivalent Co(2), and two equivalent Al(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Er(1), three equivalent Er(2), one Co(1), one Co(3), two equivalent Co(2), and two equivalent Al(2) atoms to form distorted AlEr6Al2Co4 cuboctahedra that share corners with two equivalent Co(1)Er6Al6 cuboctahedra, corners with four equivalent Al(2)Er6Al4Co2 cuboctahedra, edges with six equivalent Al(1)Er6Al2Co4 cuboctahedra, faces with two equivalent Al(1)Er6Al2Co4 cuboctahedra, faces with three equivalent Co(1)Er6Al6 cuboctahedra, and faces with six equivalent Al(2)Er6Al4Co2 cuboctahedra. In the second Al site, Al(2) is bonded to two equivalent Er(2), four equivalent Er(1), two equivalent Co(1), two equivalent Al(1), and two equivalent Al(2) atoms to form distorted AlEr6Al4Co2 cuboctahedra that share corners with four equivalent Al(1)Er6Al2Co4 cuboctahedra, corners with four equivalent Al(2)Er6Al4Co2 cuboctahedra, edges with two equivalent Al(2)Er6Al4Co2 cuboctahedra, faces with four equivalent Co(1)Er6Al6 cuboctahedra, faces with four equivalent Al(2)Er6Al4Co2 cuboctahedra, and faces with six equivalent Al(1)Er6Al2Co4 cuboctahedra. is represented by the CIF file [CIF]
data_ErAlCo
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.289
_cell_length_b   5.289
_cell_length_c   8.356
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.109
_symmetry_Int_Tables_number   1
_cell_volume   204.256
_cell_formula_units_Z   4
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  0.334  0.666  0.203  1.0
  Er  Er1  1  0.671  0.329  0.325  1.0
  Er  Er2  1  0.671  0.329  0.675  1.0
  Er  Er3  1  0.334  0.666  0.797  1.0
  Al  Al4  1  0.997  0.003  0.272  1.0
  Al  Al5  1  0.997  0.003  0.728  1.0
  Al  Al6  1  0.835  0.661  0.000  1.0
  Al  Al7  1  0.339  0.165  0.000  1.0
  Co  Co8  1  0.834  0.166  0.000  1.0
  Co  Co9  1  0.174  0.357  0.500  1.0
  Co  Co10  1  0.643  0.826  0.500  1.0
  Co  Co11  1  0.174  0.826  0.500  1.0
[/CIF]
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The compound described by ErCoAl crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 12-coordinate geometry to three equivalent Er(2), one Co(3), two equivalent Co(1), two equivalent Co(2), three equivalent Al(1), and four equivalent Al(2) atoms. In the second Er site, Er(2) is bonded in a 16-coordinate geometry to one Er(2), three equivalent Er(1), one Co(1), two equivalent Co(3), four equivalent Co(2), two equivalent Al(2), and three equivalent Al(1) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Er(2), four equivalent Er(1), two equivalent Al(1), and four equivalent Al(2) atoms to form CoEr6Al6 cuboctahedra that share corners with four equivalent Co(1)Er6Al6 cuboctahedra, corners with four equivalent Al(1)Er6Al2Co4 cuboctahedra, edges with two equivalent Co(1)Er6Al6 cuboctahedra, faces with six equivalent Al(1)Er6Al2Co4 cuboctahedra, and faces with eight equivalent Al(2)Er6Al4Co2 cuboctahedra. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to two equivalent Er(1), four equivalent Er(2), two equivalent Co(2), two equivalent Co(3), and two equivalent Al(1) atoms. In the third Co site, Co(3) is bonded in a 12-coordinate geometry to two equivalent Er(1), four equivalent Er(2), four equivalent Co(2), and two equivalent Al(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Er(1), three equivalent Er(2), one Co(1), one Co(3), two equivalent Co(2), and two equivalent Al(2) atoms to form distorted AlEr6Al2Co4 cuboctahedra that share corners with two equivalent Co(1)Er6Al6 cuboctahedra, corners with four equivalent Al(2)Er6Al4Co2 cuboctahedra, edges with six equivalent Al(1)Er6Al2Co4 cuboctahedra, faces with two equivalent Al(1)Er6Al2Co4 cuboctahedra, faces with three equivalent Co(1)Er6Al6 cuboctahedra, and faces with six equivalent Al(2)Er6Al4Co2 cuboctahedra. In the second Al site, Al(2) is bonded to two equivalent Er(2), four equivalent Er(1), two equivalent Co(1), two equivalent Al(1), and two equivalent Al(2) atoms to form distorted AlEr6Al4Co2 cuboctahedra that share corners with four equivalent Al(1)Er6Al2Co4 cuboctahedra, corners with four equivalent Al(2)Er6Al4Co2 cuboctahedra, edges with two equivalent Al(2)Er6Al4Co2 cuboctahedra, faces with four equivalent Co(1)Er6Al6 cuboctahedra, faces with four equivalent Al(2)Er6Al4Co2 cuboctahedra, and faces with six equivalent Al(1)Er6Al2Co4 cuboctahedra. is represented by the CIF file [CIF]
data_ErAlCo
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.289
_cell_length_b   5.289
_cell_length_c   8.356
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.109
_symmetry_Int_Tables_number   1
_cell_volume   204.256
_cell_formula_units_Z   4
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  0.334  0.666  0.203  1.0
  Er  Er1  1  0.671  0.329  0.325  1.0
  Er  Er2  1  0.671  0.329  0.675  1.0
  Er  Er3  1  0.334  0.666  0.797  1.0
  Al  Al4  1  0.997  0.003  0.272  1.0
  Al  Al5  1  0.997  0.003  0.728  1.0
  Al  Al6  1  0.835  0.661  0.000  1.0
  Al  Al7  1  0.339  0.165  0.000  1.0
  Co  Co8  1  0.834  0.166  0.000  1.0
  Co  Co9  1  0.174  0.357  0.500  1.0
  Co  Co10  1  0.643  0.826  0.500  1.0
  Co  Co11  1  0.174  0.826  0.500  1.0
[/CIF]
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