The compound described by Li4Cr3AlO8 is alpha Po-derived structured and crystallizes in the monoclinic C2 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form LiO6 octahedra that share corners with three equivalent Cr(1)O6 octahedra, corners with three equivalent Al(1)O6 octahedra,  an edgeedge with one Cr(1)O6 octahedra,  an edgeedge with one Al(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, and edges with four equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. In the second Li site, Li(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form LiO6 octahedra that share corners with six equivalent Cr(2)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, edges with two equivalent Al(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. In the third Li site, Li(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with six equivalent Cr(2)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, edges with two equivalent Al(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CrO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Al(1)O6 octahedra, and edges with four equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CrO6 octahedra that share corners with three equivalent Li(2)O6 octahedra, corners with three equivalent Li(3)O6 octahedra,  an edgeedge with one Li(2)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, edges with two equivalent Al(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. Al(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form AlO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with four equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-5°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Li(3), one Cr(1), and two equivalent Cr(2) atoms to form OLi3Cr3 octahedra that share corners with three equivalent O(2)Li3AlCr2 octahedra, corners with three equivalent O(1)Li3Cr3 octahedra,  an edgeedge with one O(1)Li3Cr3 octahedra, edges with three equivalent O(2)Li3AlCr2 octahedra, edges with four equivalent O(3)Li3AlCr2 octahedra, and edges with four equivalent O(4)Li3AlCr2 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Li(3), two equivalent Cr(2), and one Al(1) atom to form OLi3AlCr2 octahedra that share corners with three equivalent O(2)Li3AlCr2 octahedra, corners with three equivalent O(1)Li3Cr3 octahedra,  an edgeedge with one O(2)Li3AlCr2 octahedra, edges with three equivalent O(1)Li3Cr3 octahedra, edges with four equivalent O(3)Li3AlCr2 octahedra, and edges with four equivalent O(4)Li3AlCr2 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the third O site, O(3) is bonded to one Li(3), two equivalent Li(1), one Cr(1), one Cr(2), and one Al(1) atom to form OLi3AlCr2 octahedra that share corners with three equivalent O(3)Li3AlCr2 octahedra, corners with three equivalent O(4)Li3AlCr2 octahedra,  an edgeedge with one O(3)Li3AlCr2 octahedra, edges with three equivalent O(4)Li3AlCr2 octahedra, edges with four equivalent O(2)Li3AlCr2 octahedra, and edges with four equivalent O(1)Li3Cr3 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. In the fourth O site, O(4) is bonded to one Li(2), two equivalent Li(1), one Cr(1), one Cr(2), and one Al(1) atom to form OLi3AlCr2 octahedra that share corners with three equivalent O(3)Li3AlCr2 octahedra, corners with three equivalent O(4)Li3AlCr2 octahedra,  an edgeedge with one O(4)Li3AlCr2 octahedra, edges with three equivalent O(3)Li3AlCr2 octahedra, edges with four equivalent O(2)Li3AlCr2 octahedra, and edges with four equivalent O(1)Li3Cr3 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. is represented by the CIF card [CIF]
data_Li4AlCr3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.143
_cell_length_b   5.851
_cell_length_c   5.862
_cell_angle_alpha   60.062
_cell_angle_beta   73.462
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   144.376
_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  0.500  0.251  0.500  1.0
  Cr  Cr1  1  0.500  0.751  0.500  1.0
  Cr  Cr2  1  0.500  0.248  0.002  1.0
  Cr  Cr3  1  0.500  0.749  0.998  1.0
  Li  Li4  1  0.999  0.499  0.002  1.0
  Li  Li5  1  0.001  0.001  0.998  1.0
  Li  Li6  1  1.000  0.002  0.500  1.0
  Li  Li7  1  0.000  0.498  0.500  1.0
  O  O8  1  0.730  0.620  0.757  1.0
  O  O9  1  0.270  0.877  0.243  1.0
  O  O10  1  0.720  0.126  0.747  1.0
  O  O11  1  0.280  0.373  0.253  1.0
  O  O12  1  0.280  0.375  0.735  1.0
  O  O13  1  0.278  0.893  0.734  1.0
  O  O14  1  0.722  0.127  0.266  1.0
  O  O15  1  0.720  0.610  0.265  1.0
[/CIF]
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The compound described by Li4Cr3AlO8 is alpha Po-derived structured and crystallizes in the monoclinic C2 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form LiO6 octahedra that share corners with three equivalent Cr(1)O6 octahedra, corners with three equivalent Al(1)O6 octahedra,  an edgeedge with one Cr(1)O6 octahedra,  an edgeedge with one Al(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, and edges with four equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. In the second Li site, Li(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form LiO6 octahedra that share corners with six equivalent Cr(2)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, edges with two equivalent Al(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. In the third Li site, Li(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with six equivalent Cr(2)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, edges with two equivalent Al(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CrO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Al(1)O6 octahedra, and edges with four equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. In the second Cr site, Cr(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CrO6 octahedra that share corners with three equivalent Li(2)O6 octahedra, corners with three equivalent Li(3)O6 octahedra,  an edgeedge with one Li(2)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, edges with two equivalent Al(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-8°. Al(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form AlO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, and edges with four equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-5°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Li(3), one Cr(1), and two equivalent Cr(2) atoms to form OLi3Cr3 octahedra that share corners with three equivalent O(2)Li3AlCr2 octahedra, corners with three equivalent O(1)Li3Cr3 octahedra,  an edgeedge with one O(1)Li3Cr3 octahedra, edges with three equivalent O(2)Li3AlCr2 octahedra, edges with four equivalent O(3)Li3AlCr2 octahedra, and edges with four equivalent O(4)Li3AlCr2 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Li(3), two equivalent Cr(2), and one Al(1) atom to form OLi3AlCr2 octahedra that share corners with three equivalent O(2)Li3AlCr2 octahedra, corners with three equivalent O(1)Li3Cr3 octahedra,  an edgeedge with one O(2)Li3AlCr2 octahedra, edges with three equivalent O(1)Li3Cr3 octahedra, edges with four equivalent O(3)Li3AlCr2 octahedra, and edges with four equivalent O(4)Li3AlCr2 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the third O site, O(3) is bonded to one Li(3), two equivalent Li(1), one Cr(1), one Cr(2), and one Al(1) atom to form OLi3AlCr2 octahedra that share corners with three equivalent O(3)Li3AlCr2 octahedra, corners with three equivalent O(4)Li3AlCr2 octahedra,  an edgeedge with one O(3)Li3AlCr2 octahedra, edges with three equivalent O(4)Li3AlCr2 octahedra, edges with four equivalent O(2)Li3AlCr2 octahedra, and edges with four equivalent O(1)Li3Cr3 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. In the fourth O site, O(4) is bonded to one Li(2), two equivalent Li(1), one Cr(1), one Cr(2), and one Al(1) atom to form OLi3AlCr2 octahedra that share corners with three equivalent O(3)Li3AlCr2 octahedra, corners with three equivalent O(4)Li3AlCr2 octahedra,  an edgeedge with one O(4)Li3AlCr2 octahedra, edges with three equivalent O(3)Li3AlCr2 octahedra, edges with four equivalent O(2)Li3AlCr2 octahedra, and edges with four equivalent O(1)Li3Cr3 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. is represented by the CIF card [CIF]
data_Li4AlCr3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.143
_cell_length_b   5.851
_cell_length_c   5.862
_cell_angle_alpha   60.062
_cell_angle_beta   73.462
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   144.376
_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  0.500  0.251  0.500  1.0
  Cr  Cr1  1  0.500  0.751  0.500  1.0
  Cr  Cr2  1  0.500  0.248  0.002  1.0
  Cr  Cr3  1  0.500  0.749  0.998  1.0
  Li  Li4  1  0.999  0.499  0.002  1.0
  Li  Li5  1  0.001  0.001  0.998  1.0
  Li  Li6  1  1.000  0.002  0.500  1.0
  Li  Li7  1  0.000  0.498  0.500  1.0
  O  O8  1  0.730  0.620  0.757  1.0
  O  O9  1  0.270  0.877  0.243  1.0
  O  O10  1  0.720  0.126  0.747  1.0
  O  O11  1  0.280  0.373  0.253  1.0
  O  O12  1  0.280  0.375  0.735  1.0
  O  O13  1  0.278  0.893  0.734  1.0
  O  O14  1  0.722  0.127  0.266  1.0
  O  O15  1  0.720  0.610  0.265  1.0
[/CIF]
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