The material described by SmCu4Al crystallizes in the hexagonal P-6m2 space group. Sm(1) is bonded in a 18-coordinate geometry to three equivalent Cu(1), twelve equivalent Cu(2), and three equivalent Al(1) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to three equivalent Sm(1), six equivalent Cu(2), and three equivalent Al(1) atoms to form CuSm3Al3Cu6 cuboctahedra that share corners with nine equivalent Al(1)Sm3Cu9 cuboctahedra, corners with twelve equivalent Cu(2)Sm4Al2Cu6 cuboctahedra, edges with six equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, faces with two equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, faces with three equivalent Al(1)Sm3Cu9 cuboctahedra, and faces with eighteen equivalent Cu(2)Sm4Al2Cu6 cuboctahedra. In the second Cu site, Cu(2) is bonded to four equivalent Sm(1), two equivalent Cu(1), four equivalent Cu(2), and two equivalent Al(1) atoms to form distorted CuSm4Al2Cu6 cuboctahedra that share corners with four equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, corners with four equivalent Al(1)Sm3Cu9 cuboctahedra, corners with sixteen equivalent Cu(2)Sm4Al2Cu6 cuboctahedra, edges with ten equivalent Cu(2)Sm4Al2Cu6 cuboctahedra, faces with six equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, faces with six equivalent Al(1)Sm3Cu9 cuboctahedra, and faces with ten equivalent Cu(2)Sm4Al2Cu6 cuboctahedra. Al(1) is bonded to three equivalent Sm(1), three equivalent Cu(1), and six equivalent Cu(2) atoms to form distorted AlSm3Cu9 cuboctahedra that share corners with nine equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, corners with twelve equivalent Cu(2)Sm4Al2Cu6 cuboctahedra, edges with six equivalent Al(1)Sm3Cu9 cuboctahedra, faces with two equivalent Al(1)Sm3Cu9 cuboctahedra, faces with three equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, and faces with eighteen equivalent Cu(2)Sm4Al2Cu6 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_SmAlCu4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.273
_cell_length_b   5.273
_cell_length_c   3.996
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   96.224
_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
  Sm  Sm0  1  0.667  0.333  0.000  1.0
  Al  Al1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.333  0.667  0.000  1.0
  Cu  Cu3  1  0.664  0.832  0.500  1.0
  Cu  Cu4  1  0.168  0.832  0.500  1.0
  Cu  Cu5  1  0.168  0.336  0.500  1.0
[/CIF]
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The material described by SmCu4Al crystallizes in the hexagonal P-6m2 space group. Sm(1) is bonded in a 18-coordinate geometry to three equivalent Cu(1), twelve equivalent Cu(2), and three equivalent Al(1) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to three equivalent Sm(1), six equivalent Cu(2), and three equivalent Al(1) atoms to form CuSm3Al3Cu6 cuboctahedra that share corners with nine equivalent Al(1)Sm3Cu9 cuboctahedra, corners with twelve equivalent Cu(2)Sm4Al2Cu6 cuboctahedra, edges with six equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, faces with two equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, faces with three equivalent Al(1)Sm3Cu9 cuboctahedra, and faces with eighteen equivalent Cu(2)Sm4Al2Cu6 cuboctahedra. In the second Cu site, Cu(2) is bonded to four equivalent Sm(1), two equivalent Cu(1), four equivalent Cu(2), and two equivalent Al(1) atoms to form distorted CuSm4Al2Cu6 cuboctahedra that share corners with four equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, corners with four equivalent Al(1)Sm3Cu9 cuboctahedra, corners with sixteen equivalent Cu(2)Sm4Al2Cu6 cuboctahedra, edges with ten equivalent Cu(2)Sm4Al2Cu6 cuboctahedra, faces with six equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, faces with six equivalent Al(1)Sm3Cu9 cuboctahedra, and faces with ten equivalent Cu(2)Sm4Al2Cu6 cuboctahedra. Al(1) is bonded to three equivalent Sm(1), three equivalent Cu(1), and six equivalent Cu(2) atoms to form distorted AlSm3Cu9 cuboctahedra that share corners with nine equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, corners with twelve equivalent Cu(2)Sm4Al2Cu6 cuboctahedra, edges with six equivalent Al(1)Sm3Cu9 cuboctahedra, faces with two equivalent Al(1)Sm3Cu9 cuboctahedra, faces with three equivalent Cu(1)Sm3Al3Cu6 cuboctahedra, and faces with eighteen equivalent Cu(2)Sm4Al2Cu6 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_SmAlCu4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.273
_cell_length_b   5.273
_cell_length_c   3.996
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   96.224
_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
  Sm  Sm0  1  0.667  0.333  0.000  1.0
  Al  Al1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.333  0.667  0.000  1.0
  Cu  Cu3  1  0.664  0.832  0.500  1.0
  Cu  Cu4  1  0.168  0.832  0.500  1.0
  Cu  Cu5  1  0.168  0.336  0.500  1.0
[/CIF]
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