The material described by Er(AlC)3 crystallizes in the hexagonal P6_3/mmc space group. Er(1) is bonded to six equivalent C(1) atoms to form ErC6 octahedra that share corners with six equivalent Al(1)C4 tetrahedra, edges with six equivalent Er(1)C6 octahedra, and edges with six equivalent Al(1)C4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one C(2) and three equivalent C(1) atoms to form AlC4 tetrahedra that share corners with three equivalent Er(1)C6 octahedra, corners with seven equivalent Al(1)C4 tetrahedra, and edges with three equivalent Er(1)C6 octahedra. The corner-sharing octahedral tilt angles are 19°. In the second Al site, Al(2) is bonded in a trigonal planar geometry to three equivalent C(2) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to three equivalent Er(1) and three equivalent Al(1) atoms. In the second C site, C(2) is bonded to two equivalent Al(1) and three equivalent Al(2) atoms to form corner-sharing CAl5 trigonal bipyramids. is represented by the CIF card [CIF]
data_Er(AlC)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.402
_cell_length_b   3.402
_cell_length_c   17.153
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   171.955
_cell_formula_units_Z   2
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  0.000  0.000  0.500  1.0
  Er  Er1  1  0.000  0.000  0.000  1.0
  Al  Al2  1  0.333  0.667  0.367  1.0
  Al  Al3  1  0.667  0.333  0.633  1.0
  Al  Al4  1  0.667  0.333  0.867  1.0
  Al  Al5  1  0.333  0.667  0.133  1.0
  Al  Al6  1  0.333  0.667  0.750  1.0
  Al  Al7  1  0.667  0.333  0.250  1.0
  C  C8  1  0.333  0.667  0.908  1.0
  C  C9  1  0.667  0.333  0.092  1.0
  C  C10  1  0.667  0.333  0.408  1.0
  C  C11  1  0.333  0.667  0.592  1.0
  C  C12  1  0.333  0.667  0.250  1.0
  C  C13  1  0.667  0.333  0.750  1.0
[/CIF]
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The material described by Er(AlC)3 crystallizes in the hexagonal P6_3/mmc space group. Er(1) is bonded to six equivalent C(1) atoms to form ErC6 octahedra that share corners with six equivalent Al(1)C4 tetrahedra, edges with six equivalent Er(1)C6 octahedra, and edges with six equivalent Al(1)C4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one C(2) and three equivalent C(1) atoms to form AlC4 tetrahedra that share corners with three equivalent Er(1)C6 octahedra, corners with seven equivalent Al(1)C4 tetrahedra, and edges with three equivalent Er(1)C6 octahedra. The corner-sharing octahedral tilt angles are 19°. In the second Al site, Al(2) is bonded in a trigonal planar geometry to three equivalent C(2) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to three equivalent Er(1) and three equivalent Al(1) atoms. In the second C site, C(2) is bonded to two equivalent Al(1) and three equivalent Al(2) atoms to form corner-sharing CAl5 trigonal bipyramids. is represented by the CIF card [CIF]
data_Er(AlC)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.402
_cell_length_b   3.402
_cell_length_c   17.153
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   171.955
_cell_formula_units_Z   2
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  0.000  0.000  0.500  1.0
  Er  Er1  1  0.000  0.000  0.000  1.0
  Al  Al2  1  0.333  0.667  0.367  1.0
  Al  Al3  1  0.667  0.333  0.633  1.0
  Al  Al4  1  0.667  0.333  0.867  1.0
  Al  Al5  1  0.333  0.667  0.133  1.0
  Al  Al6  1  0.333  0.667  0.750  1.0
  Al  Al7  1  0.667  0.333  0.250  1.0
  C  C8  1  0.333  0.667  0.908  1.0
  C  C9  1  0.667  0.333  0.092  1.0
  C  C10  1  0.667  0.333  0.408  1.0
  C  C11  1  0.333  0.667  0.592  1.0
  C  C12  1  0.333  0.667  0.250  1.0
  C  C13  1  0.667  0.333  0.750  1.0
[/CIF]
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