The material described by Li2CoAlO4 is beta beryllia-derived structured and crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form LiO4 tetrahedra that share corners with four equivalent Co(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra, corners with two equivalent Li(2)O4 trigonal pyramids, and  an edgeedge with one Li(2)O4 trigonal pyramid. In the second Li site, Li(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 trigonal pyramids that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, corners with four equivalent Co(1)O4 tetrahedra,  an edgeedge with one Li(1)O4 tetrahedra, and  an edgeedge with one Al(1)O4 tetrahedra. Co(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CoO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra, and corners with four equivalent Li(2)O4 trigonal pyramids. Al(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AlO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Co(1)O4 tetrahedra, corners with two equivalent Li(2)O4 trigonal pyramids, and  an edgeedge with one Li(2)O4 trigonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Co(1), and one Al(1) atom to form a mixture of corner and edge-sharing OLi2AlCo tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Co(1), and one Al(1) atom to form a mixture of corner and edge-sharing OLi2AlCo tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Co(1), and one Al(1) atom to form a mixture of distorted corner and edge-sharing OLi2AlCo trigonal pyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Co(1), and one Al(1) atom to form corner-sharing OLi2AlCo tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2AlCoO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.832
_cell_length_b   5.134
_cell_length_c   8.093
_cell_angle_alpha   51.768
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   353.531
_cell_formula_units_Z   4
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
  Li  Li0  1  0.833  0.305  0.007  1.0
  Li  Li1  1  0.081  0.051  0.240  1.0
  Li  Li2  1  0.581  0.949  0.260  1.0
  Li  Li3  1  0.333  0.695  0.493  1.0
  Li  Li4  1  0.667  0.305  0.507  1.0
  Li  Li5  1  0.419  0.051  0.740  1.0
  Li  Li6  1  0.919  0.949  0.760  1.0
  Li  Li7  1  0.167  0.695  0.993  1.0
  Al  Al8  1  0.664  0.821  1.000  1.0
  Al  Al9  1  0.164  0.179  0.500  1.0
  Al  Al10  1  0.836  0.821  0.500  1.0
  Al  Al11  1  0.336  0.179  0.000  1.0
  Co  Co12  1  0.414  0.439  0.246  1.0
  Co  Co13  1  0.914  0.561  0.254  1.0
  Co  Co14  1  0.086  0.439  0.746  1.0
  Co  Co15  1  0.586  0.561  0.754  1.0
  O  O16  1  0.334  0.817  0.015  1.0
  O  O17  1  0.820  0.689  0.021  1.0
  O  O18  1  0.078  0.459  0.264  1.0
  O  O19  1  0.408  0.088  0.228  1.0
  O  O20  1  0.908  0.912  0.272  1.0
  O  O21  1  0.578  0.541  0.236  1.0
  O  O22  1  0.320  0.311  0.479  1.0
  O  O23  1  0.834  0.183  0.485  1.0
  O  O24  1  0.166  0.817  0.515  1.0
  O  O25  1  0.680  0.689  0.521  1.0
  O  O26  1  0.422  0.459  0.764  1.0
  O  O27  1  0.092  0.088  0.728  1.0
  O  O28  1  0.592  0.912  0.772  1.0
  O  O29  1  0.922  0.541  0.736  1.0
  O  O30  1  0.180  0.311  0.979  1.0
  O  O31  1  0.666  0.183  0.985  1.0
[/CIF]
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The material described by Li2CoAlO4 is beta beryllia-derived structured and crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form LiO4 tetrahedra that share corners with four equivalent Co(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra, corners with two equivalent Li(2)O4 trigonal pyramids, and  an edgeedge with one Li(2)O4 trigonal pyramid. In the second Li site, Li(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 trigonal pyramids that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, corners with four equivalent Co(1)O4 tetrahedra,  an edgeedge with one Li(1)O4 tetrahedra, and  an edgeedge with one Al(1)O4 tetrahedra. Co(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CoO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra, and corners with four equivalent Li(2)O4 trigonal pyramids. Al(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AlO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Co(1)O4 tetrahedra, corners with two equivalent Li(2)O4 trigonal pyramids, and  an edgeedge with one Li(2)O4 trigonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Co(1), and one Al(1) atom to form a mixture of corner and edge-sharing OLi2AlCo tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Co(1), and one Al(1) atom to form a mixture of corner and edge-sharing OLi2AlCo tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Co(1), and one Al(1) atom to form a mixture of distorted corner and edge-sharing OLi2AlCo trigonal pyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Co(1), and one Al(1) atom to form corner-sharing OLi2AlCo tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2AlCoO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.832
_cell_length_b   5.134
_cell_length_c   8.093
_cell_angle_alpha   51.768
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   353.531
_cell_formula_units_Z   4
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
  Li  Li0  1  0.833  0.305  0.007  1.0
  Li  Li1  1  0.081  0.051  0.240  1.0
  Li  Li2  1  0.581  0.949  0.260  1.0
  Li  Li3  1  0.333  0.695  0.493  1.0
  Li  Li4  1  0.667  0.305  0.507  1.0
  Li  Li5  1  0.419  0.051  0.740  1.0
  Li  Li6  1  0.919  0.949  0.760  1.0
  Li  Li7  1  0.167  0.695  0.993  1.0
  Al  Al8  1  0.664  0.821  1.000  1.0
  Al  Al9  1  0.164  0.179  0.500  1.0
  Al  Al10  1  0.836  0.821  0.500  1.0
  Al  Al11  1  0.336  0.179  0.000  1.0
  Co  Co12  1  0.414  0.439  0.246  1.0
  Co  Co13  1  0.914  0.561  0.254  1.0
  Co  Co14  1  0.086  0.439  0.746  1.0
  Co  Co15  1  0.586  0.561  0.754  1.0
  O  O16  1  0.334  0.817  0.015  1.0
  O  O17  1  0.820  0.689  0.021  1.0
  O  O18  1  0.078  0.459  0.264  1.0
  O  O19  1  0.408  0.088  0.228  1.0
  O  O20  1  0.908  0.912  0.272  1.0
  O  O21  1  0.578  0.541  0.236  1.0
  O  O22  1  0.320  0.311  0.479  1.0
  O  O23  1  0.834  0.183  0.485  1.0
  O  O24  1  0.166  0.817  0.515  1.0
  O  O25  1  0.680  0.689  0.521  1.0
  O  O26  1  0.422  0.459  0.764  1.0
  O  O27  1  0.092  0.088  0.728  1.0
  O  O28  1  0.592  0.912  0.772  1.0
  O  O29  1  0.922  0.541  0.736  1.0
  O  O30  1  0.180  0.311  0.979  1.0
  O  O31  1  0.666  0.183  0.985  1.0
[/CIF]
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