The material structure described by Er4YAl15 crystallizes in the trigonal R-3m space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to three equivalent Al(2) and nine equivalent Al(1) atoms to form ErAl12 cuboctahedra that share corners with three equivalent Er(2)Al12 cuboctahedra, corners with six equivalent Er(1)Al12 cuboctahedra, corners with six equivalent Al(3)Y2Er2Al8 cuboctahedra, edges with twelve equivalent Al(1)Er4Al8 cuboctahedra,  a faceface with one Y(1)Al12 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, faces with three equivalent Er(2)Al12 cuboctahedra, and faces with nine equivalent Al(1)Er4Al8 cuboctahedra. In the second Er site, Er(2) is bonded to three equivalent Al(1), three equivalent Al(3), and six equivalent Al(2) atoms to form ErAl12 cuboctahedra that share corners with three equivalent Er(1)Al12 cuboctahedra, corners with nine equivalent Er(2)Al12 cuboctahedra, edges with six equivalent Al(3)Y2Er2Al8 cuboctahedra, edges with nine equivalent Al(1)Er4Al8 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, faces with three equivalent Y(1)Al12 cuboctahedra, faces with three equivalent Al(1)Er4Al8 cuboctahedra, and faces with three equivalent Al(3)Y2Er2Al8 cuboctahedra. Y(1) is bonded to six equivalent Al(2) and six equivalent Al(3) atoms to form YAl12 cuboctahedra that share corners with six equivalent Y(1)Al12 cuboctahedra, corners with twelve equivalent Al(1)Er4Al8 cuboctahedra, edges with six equivalent Al(3)Y2Er2Al8 cuboctahedra, faces with two equivalent Er(1)Al12 cuboctahedra, faces with six equivalent Er(2)Al12 cuboctahedra, and faces with six equivalent Al(3)Y2Er2Al8 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one Er(2), three equivalent Er(1), two equivalent Al(2), and six equivalent Al(1) atoms to form distorted AlEr4Al8 cuboctahedra that share corners with two equivalent Y(1)Al12 cuboctahedra, corners with four equivalent Al(3)Y2Er2Al8 cuboctahedra, corners with six equivalent Al(1)Er4Al8 cuboctahedra, edges with three equivalent Er(2)Al12 cuboctahedra, edges with four equivalent Er(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Er4Al8 cuboctahedra,  a faceface with one Er(2)Al12 cuboctahedra,  a faceface with one Al(3)Y2Er2Al8 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, and faces with nine equivalent Al(1)Er4Al8 cuboctahedra. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to one Er(1), two equivalent Er(2), one Y(1), two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the third Al site, Al(3) is bonded to two equivalent Er(2), two equivalent Y(1), four equivalent Al(2), and four equivalent Al(3) atoms to form distorted AlY2Er2Al8 cuboctahedra that share corners with four equivalent Er(1)Al12 cuboctahedra, corners with six equivalent Al(3)Y2Er2Al8 cuboctahedra, corners with eight equivalent Al(1)Er4Al8 cuboctahedra, edges with two equivalent Y(1)Al12 cuboctahedra, edges with four equivalent Er(2)Al12 cuboctahedra, edges with four equivalent Al(3)Y2Er2Al8 cuboctahedra, faces with two equivalent Er(2)Al12 cuboctahedra, faces with two equivalent Y(1)Al12 cuboctahedra, faces with two equivalent Al(1)Er4Al8 cuboctahedra, and faces with four equivalent Al(3)Y2Er2Al8 cuboctahedra. is represented by the CIF file [CIF]
data_YEr4Al15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.489
_cell_length_b   12.489
_cell_length_c   12.489
_cell_angle_alpha   28.151
_cell_angle_beta   28.151
_cell_angle_gamma   28.151
_symmetry_Int_Tables_number   1
_cell_volume   383.062
_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
  Y  Y0  1  0.000  0.000  0.000  1.0
  Er  Er1  1  0.131  0.131  0.131  1.0
  Er  Er2  1  0.869  0.869  0.869  1.0
  Er  Er3  1  0.400  0.400  0.400  1.0
  Er  Er4  1  0.600  0.600  0.600  1.0
  Al  Al5  1  0.131  0.635  0.635  1.0
  Al  Al6  1  0.635  0.635  0.131  1.0
  Al  Al7  1  0.635  0.131  0.635  1.0
  Al  Al8  1  0.365  0.869  0.365  1.0
  Al  Al9  1  0.365  0.365  0.869  1.0
  Al  Al10  1  0.869  0.365  0.365  1.0
  Al  Al11  1  0.434  0.883  0.883  1.0
  Al  Al12  1  0.883  0.883  0.434  1.0
  Al  Al13  1  0.883  0.434  0.883  1.0
  Al  Al14  1  0.117  0.566  0.117  1.0
  Al  Al15  1  0.117  0.117  0.566  1.0
  Al  Al16  1  0.566  0.117  0.117  1.0
  Al  Al17  1  0.500  0.500  0.000  1.0
  Al  Al18  1  0.500  0.000  0.500  1.0
  Al  Al19  1  0.000  0.500  0.500  1.0
[/CIF]
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The material structure described by Er4YAl15 crystallizes in the trigonal R-3m space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to three equivalent Al(2) and nine equivalent Al(1) atoms to form ErAl12 cuboctahedra that share corners with three equivalent Er(2)Al12 cuboctahedra, corners with six equivalent Er(1)Al12 cuboctahedra, corners with six equivalent Al(3)Y2Er2Al8 cuboctahedra, edges with twelve equivalent Al(1)Er4Al8 cuboctahedra,  a faceface with one Y(1)Al12 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, faces with three equivalent Er(2)Al12 cuboctahedra, and faces with nine equivalent Al(1)Er4Al8 cuboctahedra. In the second Er site, Er(2) is bonded to three equivalent Al(1), three equivalent Al(3), and six equivalent Al(2) atoms to form ErAl12 cuboctahedra that share corners with three equivalent Er(1)Al12 cuboctahedra, corners with nine equivalent Er(2)Al12 cuboctahedra, edges with six equivalent Al(3)Y2Er2Al8 cuboctahedra, edges with nine equivalent Al(1)Er4Al8 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, faces with three equivalent Y(1)Al12 cuboctahedra, faces with three equivalent Al(1)Er4Al8 cuboctahedra, and faces with three equivalent Al(3)Y2Er2Al8 cuboctahedra. Y(1) is bonded to six equivalent Al(2) and six equivalent Al(3) atoms to form YAl12 cuboctahedra that share corners with six equivalent Y(1)Al12 cuboctahedra, corners with twelve equivalent Al(1)Er4Al8 cuboctahedra, edges with six equivalent Al(3)Y2Er2Al8 cuboctahedra, faces with two equivalent Er(1)Al12 cuboctahedra, faces with six equivalent Er(2)Al12 cuboctahedra, and faces with six equivalent Al(3)Y2Er2Al8 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one Er(2), three equivalent Er(1), two equivalent Al(2), and six equivalent Al(1) atoms to form distorted AlEr4Al8 cuboctahedra that share corners with two equivalent Y(1)Al12 cuboctahedra, corners with four equivalent Al(3)Y2Er2Al8 cuboctahedra, corners with six equivalent Al(1)Er4Al8 cuboctahedra, edges with three equivalent Er(2)Al12 cuboctahedra, edges with four equivalent Er(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Er4Al8 cuboctahedra,  a faceface with one Er(2)Al12 cuboctahedra,  a faceface with one Al(3)Y2Er2Al8 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, and faces with nine equivalent Al(1)Er4Al8 cuboctahedra. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to one Er(1), two equivalent Er(2), one Y(1), two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the third Al site, Al(3) is bonded to two equivalent Er(2), two equivalent Y(1), four equivalent Al(2), and four equivalent Al(3) atoms to form distorted AlY2Er2Al8 cuboctahedra that share corners with four equivalent Er(1)Al12 cuboctahedra, corners with six equivalent Al(3)Y2Er2Al8 cuboctahedra, corners with eight equivalent Al(1)Er4Al8 cuboctahedra, edges with two equivalent Y(1)Al12 cuboctahedra, edges with four equivalent Er(2)Al12 cuboctahedra, edges with four equivalent Al(3)Y2Er2Al8 cuboctahedra, faces with two equivalent Er(2)Al12 cuboctahedra, faces with two equivalent Y(1)Al12 cuboctahedra, faces with two equivalent Al(1)Er4Al8 cuboctahedra, and faces with four equivalent Al(3)Y2Er2Al8 cuboctahedra. is represented by the CIF file [CIF]
data_YEr4Al15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.489
_cell_length_b   12.489
_cell_length_c   12.489
_cell_angle_alpha   28.151
_cell_angle_beta   28.151
_cell_angle_gamma   28.151
_symmetry_Int_Tables_number   1
_cell_volume   383.062
_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
  Y  Y0  1  0.000  0.000  0.000  1.0
  Er  Er1  1  0.131  0.131  0.131  1.0
  Er  Er2  1  0.869  0.869  0.869  1.0
  Er  Er3  1  0.400  0.400  0.400  1.0
  Er  Er4  1  0.600  0.600  0.600  1.0
  Al  Al5  1  0.131  0.635  0.635  1.0
  Al  Al6  1  0.635  0.635  0.131  1.0
  Al  Al7  1  0.635  0.131  0.635  1.0
  Al  Al8  1  0.365  0.869  0.365  1.0
  Al  Al9  1  0.365  0.365  0.869  1.0
  Al  Al10  1  0.869  0.365  0.365  1.0
  Al  Al11  1  0.434  0.883  0.883  1.0
  Al  Al12  1  0.883  0.883  0.434  1.0
  Al  Al13  1  0.883  0.434  0.883  1.0
  Al  Al14  1  0.117  0.566  0.117  1.0
  Al  Al15  1  0.117  0.117  0.566  1.0
  Al  Al16  1  0.566  0.117  0.117  1.0
  Al  Al17  1  0.500  0.500  0.000  1.0
  Al  Al18  1  0.500  0.000  0.500  1.0
  Al  Al19  1  0.000  0.500  0.500  1.0
[/CIF]
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