The compound described by Sc2Al4(CO)3 crystallizes in the trigonal R3m space group. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 6-coordinate geometry to three equivalent C(1) and three equivalent C(2) atoms. In the second Sc site, Sc(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent C(3) and one O(2) atom to form AlC3O trigonal pyramids that share corners with three equivalent Al(3)C4 tetrahedra and corners with six equivalent Al(1)C3O trigonal pyramids. In the second Al site, Al(2) is bonded in a 4-coordinate geometry to one C(2), one O(1), and three equivalent O(3) atoms. In the third Al site, Al(3) is bonded to one C(3) and three equivalent C(1) atoms to form distorted AlC4 tetrahedra that share corners with six equivalent Al(3)C4 tetrahedra and corners with three equivalent Al(1)C3O trigonal pyramids. In the fourth Al site, Al(4) is bonded to three equivalent C(2) and one O(3) atom to form distorted corner-sharing AlC3O trigonal pyramids. There are three inequivalent C sites. In the first C site, C(1) is bonded to three equivalent Sc(1) and three equivalent Al(3) atoms to form CSc3Al3 octahedra that share corners with three equivalent C(3)Al4 trigonal pyramids and edges with six equivalent C(1)Sc3Al3 octahedra. In the second C site, C(2) is bonded in a 7-coordinate geometry to three equivalent Sc(1), one Al(2), and three equivalent Al(4) atoms. In the third C site, C(3) is bonded to one Al(3) and three equivalent Al(1) atoms to form distorted CAl4 trigonal pyramids that share corners with three equivalent C(1)Sc3Al3 octahedra, corners with three equivalent O(2)Sc3Al tetrahedra, and corners with six equivalent C(3)Al4 trigonal pyramids. The corner-sharing octahedral tilt angles are 63°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Sc(2) and one Al(2) atom. In the second O site, O(2) is bonded to three equivalent Sc(2) and one Al(1) atom to form OSc3Al tetrahedra that share corners with six equivalent O(2)Sc3Al tetrahedra and corners with three equivalent C(3)Al4 trigonal pyramids. In the third O site, O(3) is bonded to one Al(4) and three equivalent Al(2) atoms to form corner-sharing OAl4 trigonal pyramids. is represented by the CIF file [CIF]
data_Sc2Al4(CO)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.413
_cell_length_b   14.413
_cell_length_c   14.413
_cell_angle_alpha   13.394
_cell_angle_beta   13.394
_cell_angle_gamma   13.394
_symmetry_Int_Tables_number   1
_cell_volume   139.784
_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
  Sc  Sc0  1  0.001  0.001  0.001  1.0
  Sc  Sc1  1  0.497  0.497  0.497  1.0
  Al  Al2  1  0.770  0.770  0.770  1.0
  Al  Al3  1  0.234  0.234  0.234  1.0
  Al  Al4  1  0.384  0.384  0.384  1.0
  Al  Al5  1  0.617  0.617  0.617  1.0
  C  C6  1  0.695  0.695  0.695  1.0
  C  C7  1  0.292  0.292  0.292  1.0
  C  C8  1  0.429  0.429  0.429  1.0
  O  O9  1  0.193  0.193  0.193  1.0
  O  O10  1  0.815  0.815  0.815  1.0
  O  O11  1  0.573  0.573  0.573  1.0
[/CIF]
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The compound described by Sc2Al4(CO)3 crystallizes in the trigonal R3m space group. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 6-coordinate geometry to three equivalent C(1) and three equivalent C(2) atoms. In the second Sc site, Sc(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent C(3) and one O(2) atom to form AlC3O trigonal pyramids that share corners with three equivalent Al(3)C4 tetrahedra and corners with six equivalent Al(1)C3O trigonal pyramids. In the second Al site, Al(2) is bonded in a 4-coordinate geometry to one C(2), one O(1), and three equivalent O(3) atoms. In the third Al site, Al(3) is bonded to one C(3) and three equivalent C(1) atoms to form distorted AlC4 tetrahedra that share corners with six equivalent Al(3)C4 tetrahedra and corners with three equivalent Al(1)C3O trigonal pyramids. In the fourth Al site, Al(4) is bonded to three equivalent C(2) and one O(3) atom to form distorted corner-sharing AlC3O trigonal pyramids. There are three inequivalent C sites. In the first C site, C(1) is bonded to three equivalent Sc(1) and three equivalent Al(3) atoms to form CSc3Al3 octahedra that share corners with three equivalent C(3)Al4 trigonal pyramids and edges with six equivalent C(1)Sc3Al3 octahedra. In the second C site, C(2) is bonded in a 7-coordinate geometry to three equivalent Sc(1), one Al(2), and three equivalent Al(4) atoms. In the third C site, C(3) is bonded to one Al(3) and three equivalent Al(1) atoms to form distorted CAl4 trigonal pyramids that share corners with three equivalent C(1)Sc3Al3 octahedra, corners with three equivalent O(2)Sc3Al tetrahedra, and corners with six equivalent C(3)Al4 trigonal pyramids. The corner-sharing octahedral tilt angles are 63°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Sc(2) and one Al(2) atom. In the second O site, O(2) is bonded to three equivalent Sc(2) and one Al(1) atom to form OSc3Al tetrahedra that share corners with six equivalent O(2)Sc3Al tetrahedra and corners with three equivalent C(3)Al4 trigonal pyramids. In the third O site, O(3) is bonded to one Al(4) and three equivalent Al(2) atoms to form corner-sharing OAl4 trigonal pyramids. is represented by the CIF file [CIF]
data_Sc2Al4(CO)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.413
_cell_length_b   14.413
_cell_length_c   14.413
_cell_angle_alpha   13.394
_cell_angle_beta   13.394
_cell_angle_gamma   13.394
_symmetry_Int_Tables_number   1
_cell_volume   139.784
_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
  Sc  Sc0  1  0.001  0.001  0.001  1.0
  Sc  Sc1  1  0.497  0.497  0.497  1.0
  Al  Al2  1  0.770  0.770  0.770  1.0
  Al  Al3  1  0.234  0.234  0.234  1.0
  Al  Al4  1  0.384  0.384  0.384  1.0
  Al  Al5  1  0.617  0.617  0.617  1.0
  C  C6  1  0.695  0.695  0.695  1.0
  C  C7  1  0.292  0.292  0.292  1.0
  C  C8  1  0.429  0.429  0.429  1.0
  O  O9  1  0.193  0.193  0.193  1.0
  O  O10  1  0.815  0.815  0.815  1.0
  O  O11  1  0.573  0.573  0.573  1.0
[/CIF]
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