The compound described by Li2MgMn3O8 is Spinel-derived structured and crystallizes in the trigonal R-3m space group. Li(1) is bonded to one O(1) and three equivalent O(2) atoms to form LiO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with nine equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-62°. Mg(1) is bonded to six equivalent O(2) atoms to form MgO6 octahedra that share corners with six equivalent Li(1)O4 tetrahedra and edges with six equivalent Mn(1)O6 octahedra. Mn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Li(1)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(1) and three equivalent Mn(1) atoms to form distorted OLiMn3 trigonal pyramids that share corners with three equivalent O(1)LiMn3 trigonal pyramids, corners with nine equivalent O(2)LiMgMn2 trigonal pyramids, and edges with three equivalent O(2)LiMgMn2 trigonal pyramids. In the second O site, O(2) is bonded to one Li(1), one Mg(1), and two equivalent Mn(1) atoms to form distorted OLiMgMn2 trigonal pyramids that share corners with three equivalent O(1)LiMn3 trigonal pyramids, corners with nine equivalent O(2)LiMgMn2 trigonal pyramids,  an edgeedge with one O(1)LiMn3 trigonal pyramid, and edges with two equivalent O(2)LiMgMn2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2MgMn3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.953
_cell_length_b   5.953
_cell_length_c   5.953
_cell_angle_alpha   58.727
_cell_angle_beta   58.727
_cell_angle_gamma   58.727
_symmetry_Int_Tables_number   1
_cell_volume   144.861
_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  0.116  0.116  0.116  1.0
  Li  Li1  1  0.884  0.884  0.884  1.0
  Mg  Mg2  1  0.500  0.500  0.500  1.0
  Mn  Mn3  1  0.500  0.500  0.000  1.0
  Mn  Mn4  1  0.500  0.000  0.500  1.0
  Mn  Mn5  1  0.000  0.500  0.500  1.0
  O  O6  1  0.263  0.263  0.263  1.0
  O  O7  1  0.709  0.254  0.254  1.0
  O  O8  1  0.254  0.709  0.254  1.0
  O  O9  1  0.254  0.254  0.709  1.0
  O  O10  1  0.746  0.746  0.291  1.0
  O  O11  1  0.746  0.291  0.746  1.0
  O  O12  1  0.291  0.746  0.746  1.0
  O  O13  1  0.737  0.737  0.737  1.0
[/CIF]
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The compound described by Li2MgMn3O8 is Spinel-derived structured and crystallizes in the trigonal R-3m space group. Li(1) is bonded to one O(1) and three equivalent O(2) atoms to form LiO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with nine equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 59-62°. Mg(1) is bonded to six equivalent O(2) atoms to form MgO6 octahedra that share corners with six equivalent Li(1)O4 tetrahedra and edges with six equivalent Mn(1)O6 octahedra. Mn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Li(1)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(1) and three equivalent Mn(1) atoms to form distorted OLiMn3 trigonal pyramids that share corners with three equivalent O(1)LiMn3 trigonal pyramids, corners with nine equivalent O(2)LiMgMn2 trigonal pyramids, and edges with three equivalent O(2)LiMgMn2 trigonal pyramids. In the second O site, O(2) is bonded to one Li(1), one Mg(1), and two equivalent Mn(1) atoms to form distorted OLiMgMn2 trigonal pyramids that share corners with three equivalent O(1)LiMn3 trigonal pyramids, corners with nine equivalent O(2)LiMgMn2 trigonal pyramids,  an edgeedge with one O(1)LiMn3 trigonal pyramid, and edges with two equivalent O(2)LiMgMn2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2MgMn3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.953
_cell_length_b   5.953
_cell_length_c   5.953
_cell_angle_alpha   58.727
_cell_angle_beta   58.727
_cell_angle_gamma   58.727
_symmetry_Int_Tables_number   1
_cell_volume   144.861
_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  0.116  0.116  0.116  1.0
  Li  Li1  1  0.884  0.884  0.884  1.0
  Mg  Mg2  1  0.500  0.500  0.500  1.0
  Mn  Mn3  1  0.500  0.500  0.000  1.0
  Mn  Mn4  1  0.500  0.000  0.500  1.0
  Mn  Mn5  1  0.000  0.500  0.500  1.0
  O  O6  1  0.263  0.263  0.263  1.0
  O  O7  1  0.709  0.254  0.254  1.0
  O  O8  1  0.254  0.709  0.254  1.0
  O  O9  1  0.254  0.254  0.709  1.0
  O  O10  1  0.746  0.746  0.291  1.0
  O  O11  1  0.746  0.291  0.746  1.0
  O  O12  1  0.291  0.746  0.746  1.0
  O  O13  1  0.737  0.737  0.737  1.0
[/CIF]
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