The compound described by SrCo2Al9 crystallizes in the hexagonal P6/mmm space group. Sr(1) is bonded to twelve equivalent Al(2) atoms to form face-sharing SrAl12 cuboctahedra. Co(1) is bonded in a 9-coordinate geometry to three equivalent Al(1) and six equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a linear geometry to two equivalent Co(1) and eight equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to two equivalent Sr(1), two equivalent Co(1), four equivalent Al(1), and four equivalent Al(2) atoms. is represented by the CIF card [CIF]
data_SrAl9Co2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.843
_cell_length_b   7.843
_cell_length_c   3.897
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   207.621
_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
  Sr  Sr0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.500  0.000  0.000  1.0
  Al  Al2  1  0.500  0.500  0.000  1.0
  Al  Al3  1  0.000  0.500  0.000  1.0
  Al  Al4  1  0.215  0.431  0.500  1.0
  Al  Al5  1  0.785  0.215  0.500  1.0
  Al  Al6  1  0.431  0.215  0.500  1.0
  Al  Al7  1  0.569  0.785  0.500  1.0
  Al  Al8  1  0.215  0.785  0.500  1.0
  Al  Al9  1  0.785  0.569  0.500  1.0
  Co  Co10  1  0.333  0.667  0.000  1.0
  Co  Co11  1  0.667  0.333  0.000  1.0
[/CIF]
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The compound described by SrCo2Al9 crystallizes in the hexagonal P6/mmm space group. Sr(1) is bonded to twelve equivalent Al(2) atoms to form face-sharing SrAl12 cuboctahedra. Co(1) is bonded in a 9-coordinate geometry to three equivalent Al(1) and six equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a linear geometry to two equivalent Co(1) and eight equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to two equivalent Sr(1), two equivalent Co(1), four equivalent Al(1), and four equivalent Al(2) atoms. is represented by the CIF card [CIF]
data_SrAl9Co2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.843
_cell_length_b   7.843
_cell_length_c   3.897
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   207.621
_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
  Sr  Sr0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.500  0.000  0.000  1.0
  Al  Al2  1  0.500  0.500  0.000  1.0
  Al  Al3  1  0.000  0.500  0.000  1.0
  Al  Al4  1  0.215  0.431  0.500  1.0
  Al  Al5  1  0.785  0.215  0.500  1.0
  Al  Al6  1  0.431  0.215  0.500  1.0
  Al  Al7  1  0.569  0.785  0.500  1.0
  Al  Al8  1  0.215  0.785  0.500  1.0
  Al  Al9  1  0.785  0.569  0.500  1.0
  Co  Co10  1  0.333  0.667  0.000  1.0
  Co  Co11  1  0.667  0.333  0.000  1.0
[/CIF]
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