The crystal structure described by Al4CO crystallizes in the monoclinic Cm space group. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Al(4) and two equivalent C(1) atoms. In the second Al site, Al(2) is bonded in a single-bond geometry to two equivalent Al(3) and one O(1) atom. In the third Al site, Al(3) is bonded to two equivalent Al(2), two equivalent Al(3), and two equivalent Al(4) atoms to form a mixture of corner and edge-sharing AlAl6 octahedra. The corner-sharing octahedra are not tilted. In the fourth Al site, Al(4) is bonded to two equivalent Al(1), two equivalent Al(3), and two equivalent Al(4) atoms to form distorted AlAl6 octahedra that share corners with two equivalent Al(4)Al6 octahedra, corners with two equivalent C(1)Al2O2 tetrahedra, edges with two equivalent Al(4)Al6 octahedra, edges with four equivalent Al(3)Al6 octahedra, and  an edgeedge with one C(1)Al2O2 tetrahedra. The corner-sharing octahedra are not tilted. C(1) is bonded to two equivalent Al(1) and two equivalent O(1) atoms to form distorted CAl2O2 tetrahedra that share corners with two equivalent Al(4)Al6 octahedra, corners with four equivalent C(1)Al2O2 tetrahedra, and  an edgeedge with one Al(4)Al6 octahedra. The corner-sharing octahedral tilt angles range from 14-22°. O(1) is bonded in a trigonal planar geometry to one Al(2) and two equivalent C(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al4CO
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.557
_cell_length_b   4.764
_cell_length_c   9.431
_cell_angle_alpha   85.899
_cell_angle_beta   97.790
_cell_angle_gamma   122.452
_symmetry_Int_Tables_number   1
_cell_volume   96.045
_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
  Al  Al0  1  0.293  0.511  0.563  1.0
  Al  Al1  1  0.563  0.072  0.982  1.0
  Al  Al2  1  0.149  0.569  0.158  1.0
  Al  Al3  1  0.745  0.075  0.340  1.0
  C  C4  1  0.860  0.021  0.678  1.0
  O  O5  1  0.390  0.001  0.778  1.0
[/CIF]
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The crystal structure described by Al4CO crystallizes in the monoclinic Cm space group. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Al(4) and two equivalent C(1) atoms. In the second Al site, Al(2) is bonded in a single-bond geometry to two equivalent Al(3) and one O(1) atom. In the third Al site, Al(3) is bonded to two equivalent Al(2), two equivalent Al(3), and two equivalent Al(4) atoms to form a mixture of corner and edge-sharing AlAl6 octahedra. The corner-sharing octahedra are not tilted. In the fourth Al site, Al(4) is bonded to two equivalent Al(1), two equivalent Al(3), and two equivalent Al(4) atoms to form distorted AlAl6 octahedra that share corners with two equivalent Al(4)Al6 octahedra, corners with two equivalent C(1)Al2O2 tetrahedra, edges with two equivalent Al(4)Al6 octahedra, edges with four equivalent Al(3)Al6 octahedra, and  an edgeedge with one C(1)Al2O2 tetrahedra. The corner-sharing octahedra are not tilted. C(1) is bonded to two equivalent Al(1) and two equivalent O(1) atoms to form distorted CAl2O2 tetrahedra that share corners with two equivalent Al(4)Al6 octahedra, corners with four equivalent C(1)Al2O2 tetrahedra, and  an edgeedge with one Al(4)Al6 octahedra. The corner-sharing octahedral tilt angles range from 14-22°. O(1) is bonded in a trigonal planar geometry to one Al(2) and two equivalent C(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al4CO
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.557
_cell_length_b   4.764
_cell_length_c   9.431
_cell_angle_alpha   85.899
_cell_angle_beta   97.790
_cell_angle_gamma   122.452
_symmetry_Int_Tables_number   1
_cell_volume   96.045
_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
  Al  Al0  1  0.293  0.511  0.563  1.0
  Al  Al1  1  0.563  0.072  0.982  1.0
  Al  Al2  1  0.149  0.569  0.158  1.0
  Al  Al3  1  0.745  0.075  0.340  1.0
  C  C4  1  0.860  0.021  0.678  1.0
  O  O5  1  0.390  0.001  0.778  1.0
[/CIF]
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