The material described by Li4Fe3CoO8 is Caswellsilverite-derived structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form LiO6 octahedra that share corners with three equivalent Fe(2)O6 octahedra, corners with three equivalent Co(1)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with four equivalent Li(2)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-7°. In the second Li site, Li(2) 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 Fe(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-7°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent Li(2)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-7°. In the second Fe site, Fe(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form FeO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with four equivalent Li(2)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 7°. Co(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form CoO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with four equivalent Li(2)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), two equivalent Li(1), one Fe(1), one Fe(2), and one Co(1) atom to form OLi3Fe2Co octahedra that share corners with six equivalent O(1)Li3Fe2Co octahedra, edges with four equivalent O(1)Li3Fe2Co octahedra, edges with four equivalent O(3)Li3Fe2Co octahedra, and edges with four equivalent O(2)Li3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second O site, O(2) is bonded to one Li(1), two equivalent Li(2), one Fe(2), and two equivalent Fe(1) atoms to form OLi3Fe3 octahedra that share corners with three equivalent O(3)Li3Fe2Co octahedra, corners with three equivalent O(2)Li3Fe3 octahedra,  an edgeedge with one O(2)Li3Fe3 octahedra, edges with three equivalent O(3)Li3Fe2Co octahedra, and edges with eight equivalent O(1)Li3Fe2Co octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the third O site, O(3) is bonded to one Li(1), two equivalent Li(2), two equivalent Fe(1), and one Co(1) atom to form OLi3Fe2Co octahedra that share corners with three equivalent O(3)Li3Fe2Co octahedra, corners with three equivalent O(2)Li3Fe3 octahedra,  an edgeedge with one O(3)Li3Fe2Co octahedra, edges with three equivalent O(2)Li3Fe3 octahedra, and edges with eight equivalent O(1)Li3Fe2Co octahedra. The corner-sharing octahedral tilt angles range from 0-6°. is represented by the CIF card [CIF]
data_Li4Fe3CoO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.952
_cell_length_b   5.952
_cell_length_c   5.099
_cell_angle_alpha   73.256
_cell_angle_beta   73.256
_cell_angle_gamma   59.331
_symmetry_Int_Tables_number   1
_cell_volume   146.588
_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
  Li  Li0  1  0.246  0.246  0.526  1.0
  Li  Li1  1  0.754  0.754  0.474  1.0
  Li  Li2  1  0.500  0.000  0.000  1.0
  Li  Li3  1  0.000  0.500  0.000  1.0
  Fe  Fe4  1  0.246  0.754  0.500  1.0
  Fe  Fe5  1  0.754  0.246  0.500  1.0
  Fe  Fe6  1  0.500  0.500  0.000  1.0
  Co  Co7  1  0.000  0.000  0.000  1.0
  O  O8  1  0.872  0.353  0.763  1.0
  O  O9  1  0.353  0.872  0.763  1.0
  O  O10  1  0.384  0.384  0.742  1.0
  O  O11  1  0.888  0.888  0.755  1.0
  O  O12  1  0.112  0.112  0.245  1.0
  O  O13  1  0.616  0.616  0.258  1.0
  O  O14  1  0.647  0.128  0.237  1.0
  O  O15  1  0.128  0.647  0.237  1.0
[/CIF]
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The material described by Li4Fe3CoO8 is Caswellsilverite-derived structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form LiO6 octahedra that share corners with three equivalent Fe(2)O6 octahedra, corners with three equivalent Co(1)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with four equivalent Li(2)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-7°. In the second Li site, Li(2) 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 Fe(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-7°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent Li(2)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-7°. In the second Fe site, Fe(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form FeO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with four equivalent Li(2)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 7°. Co(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form CoO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with four equivalent Li(2)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), two equivalent Li(1), one Fe(1), one Fe(2), and one Co(1) atom to form OLi3Fe2Co octahedra that share corners with six equivalent O(1)Li3Fe2Co octahedra, edges with four equivalent O(1)Li3Fe2Co octahedra, edges with four equivalent O(3)Li3Fe2Co octahedra, and edges with four equivalent O(2)Li3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second O site, O(2) is bonded to one Li(1), two equivalent Li(2), one Fe(2), and two equivalent Fe(1) atoms to form OLi3Fe3 octahedra that share corners with three equivalent O(3)Li3Fe2Co octahedra, corners with three equivalent O(2)Li3Fe3 octahedra,  an edgeedge with one O(2)Li3Fe3 octahedra, edges with three equivalent O(3)Li3Fe2Co octahedra, and edges with eight equivalent O(1)Li3Fe2Co octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the third O site, O(3) is bonded to one Li(1), two equivalent Li(2), two equivalent Fe(1), and one Co(1) atom to form OLi3Fe2Co octahedra that share corners with three equivalent O(3)Li3Fe2Co octahedra, corners with three equivalent O(2)Li3Fe3 octahedra,  an edgeedge with one O(3)Li3Fe2Co octahedra, edges with three equivalent O(2)Li3Fe3 octahedra, and edges with eight equivalent O(1)Li3Fe2Co octahedra. The corner-sharing octahedral tilt angles range from 0-6°. is represented by the CIF card [CIF]
data_Li4Fe3CoO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.952
_cell_length_b   5.952
_cell_length_c   5.099
_cell_angle_alpha   73.256
_cell_angle_beta   73.256
_cell_angle_gamma   59.331
_symmetry_Int_Tables_number   1
_cell_volume   146.588
_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
  Li  Li0  1  0.246  0.246  0.526  1.0
  Li  Li1  1  0.754  0.754  0.474  1.0
  Li  Li2  1  0.500  0.000  0.000  1.0
  Li  Li3  1  0.000  0.500  0.000  1.0
  Fe  Fe4  1  0.246  0.754  0.500  1.0
  Fe  Fe5  1  0.754  0.246  0.500  1.0
  Fe  Fe6  1  0.500  0.500  0.000  1.0
  Co  Co7  1  0.000  0.000  0.000  1.0
  O  O8  1  0.872  0.353  0.763  1.0
  O  O9  1  0.353  0.872  0.763  1.0
  O  O10  1  0.384  0.384  0.742  1.0
  O  O11  1  0.888  0.888  0.755  1.0
  O  O12  1  0.112  0.112  0.245  1.0
  O  O13  1  0.616  0.616  0.258  1.0
  O  O14  1  0.647  0.128  0.237  1.0
  O  O15  1  0.128  0.647  0.237  1.0
[/CIF]
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