The material described by Li2MnCuO4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted LiO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Li(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-17°. In the second Li site, Li(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form LiO6 octahedra that share edges with two equivalent Li(2)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Li(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-17°. Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), two equivalent Li(1), two equivalent Mn(1), and one Cu(1) atom to form distorted OLi3Mn2Cu octahedra that share corners with six equivalent O(1)Li3Mn2Cu octahedra, corners with two equivalent O(2)Li3MnCu square pyramids, edges with four equivalent O(1)Li3Mn2Cu octahedra, and edges with six equivalent O(2)Li3MnCu square pyramids. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to one Li(1), two equivalent Li(2), one Mn(1), and one Cu(1) atom to form distorted OLi3MnCu square pyramids that share corners with two equivalent O(1)Li3Mn2Cu octahedra, corners with seven equivalent O(2)Li3MnCu square pyramids, edges with six equivalent O(1)Li3Mn2Cu octahedra, and  an edgeedge with one O(2)Li3MnCu square pyramid. The corner-sharing octahedral tilt angles are 85°. is represented by the CIF file [CIF]
data_Li2MnCuO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.623
_cell_length_b   5.623
_cell_length_c   6.264
_cell_angle_alpha   63.846
_cell_angle_beta   63.844
_cell_angle_gamma   90.023
_symmetry_Int_Tables_number   1
_cell_volume   154.833
_cell_formula_units_Z   2
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  0.500  0.000  0.000  1.0
  Li  Li1  1  0.500  0.000  0.500  1.0
  Li  Li2  1  1.000  0.000  0.500  1.0
  Li  Li3  1  0.500  0.500  0.000  1.0
  Mn  Mn4  1  0.000  0.500  1.000  1.0
  Mn  Mn5  1  0.000  0.500  0.500  1.0
  Cu  Cu6  1  0.500  0.500  0.500  1.0
  Cu  Cu7  1  1.000  1.000  0.000  1.0
  O  O8  1  0.781  0.251  0.978  1.0
  O  O9  1  0.249  0.719  0.522  1.0
  O  O10  1  0.751  0.281  0.478  1.0
  O  O11  1  0.219  0.749  0.022  1.0
  O  O12  1  0.198  0.214  0.055  1.0
  O  O13  1  0.286  0.302  0.445  1.0
  O  O14  1  0.714  0.698  0.555  1.0
  O  O15  1  0.802  0.786  0.945  1.0
[/CIF]
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The material described by Li2MnCuO4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted LiO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Li(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-17°. In the second Li site, Li(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form LiO6 octahedra that share edges with two equivalent Li(2)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with four equivalent Li(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-17°. Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), two equivalent Li(1), two equivalent Mn(1), and one Cu(1) atom to form distorted OLi3Mn2Cu octahedra that share corners with six equivalent O(1)Li3Mn2Cu octahedra, corners with two equivalent O(2)Li3MnCu square pyramids, edges with four equivalent O(1)Li3Mn2Cu octahedra, and edges with six equivalent O(2)Li3MnCu square pyramids. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to one Li(1), two equivalent Li(2), one Mn(1), and one Cu(1) atom to form distorted OLi3MnCu square pyramids that share corners with two equivalent O(1)Li3Mn2Cu octahedra, corners with seven equivalent O(2)Li3MnCu square pyramids, edges with six equivalent O(1)Li3Mn2Cu octahedra, and  an edgeedge with one O(2)Li3MnCu square pyramid. The corner-sharing octahedral tilt angles are 85°. is represented by the CIF file [CIF]
data_Li2MnCuO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.623
_cell_length_b   5.623
_cell_length_c   6.264
_cell_angle_alpha   63.846
_cell_angle_beta   63.844
_cell_angle_gamma   90.023
_symmetry_Int_Tables_number   1
_cell_volume   154.833
_cell_formula_units_Z   2
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  0.500  0.000  0.000  1.0
  Li  Li1  1  0.500  0.000  0.500  1.0
  Li  Li2  1  1.000  0.000  0.500  1.0
  Li  Li3  1  0.500  0.500  0.000  1.0
  Mn  Mn4  1  0.000  0.500  1.000  1.0
  Mn  Mn5  1  0.000  0.500  0.500  1.0
  Cu  Cu6  1  0.500  0.500  0.500  1.0
  Cu  Cu7  1  1.000  1.000  0.000  1.0
  O  O8  1  0.781  0.251  0.978  1.0
  O  O9  1  0.249  0.719  0.522  1.0
  O  O10  1  0.751  0.281  0.478  1.0
  O  O11  1  0.219  0.749  0.022  1.0
  O  O12  1  0.198  0.214  0.055  1.0
  O  O13  1  0.286  0.302  0.445  1.0
  O  O14  1  0.714  0.698  0.555  1.0
  O  O15  1  0.802  0.786  0.945  1.0
[/CIF]
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