The compound described by Mg2Mn3O8 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(3), two equivalent O(5), and two equivalent O(6) atoms to form MgO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra, corners with four equivalent Mn(2)O6 octahedra, corners with two equivalent Mg(2)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-55°. In the second Mg site, Mg(2) is bonded to one O(2), one O(4), and two equivalent O(5) atoms to form MgO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Mn(1)O6 octahedra, and corners with six equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-63°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(3), two equivalent O(5), and two equivalent O(6) atoms to form MnO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Mg(2)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form MnO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Mg(2)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Mn(1), and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Mg(2) and two equivalent Mn(2) atoms. In the fifth O site, O(5) is bonded to one Mg(1), one Mg(2), one Mn(1), and one Mn(2) atom to form a mixture of distorted corner and edge-sharing OMg2Mn2 tetrahedra. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Mg(1), one Mn(1), and one Mn(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Mn3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.880
_cell_length_b   5.747
_cell_length_c   9.377
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   263.017
_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
  Mg  Mg0  1  0.815  0.500  0.221  1.0
  Mg  Mg1  1  0.822  0.500  0.815  1.0
  Mg  Mg2  1  0.178  0.000  0.315  1.0
  Mg  Mg3  1  0.185  0.000  0.721  1.0
  Mn  Mn4  1  0.184  0.500  0.498  1.0
  Mn  Mn5  1  0.323  0.740  0.000  1.0
  Mn  Mn6  1  0.677  0.760  0.500  1.0
  Mn  Mn7  1  0.816  0.000  0.998  1.0
  Mn  Mn8  1  0.677  0.240  0.500  1.0
  Mn  Mn9  1  0.323  0.260  0.000  1.0
  O  O10  1  0.178  0.500  0.108  1.0
  O  O11  1  0.851  0.500  0.605  1.0
  O  O12  1  0.515  0.500  0.392  1.0
  O  O13  1  0.448  0.500  0.887  1.0
  O  O14  1  0.992  0.721  0.381  1.0
  O  O15  1  0.353  0.737  0.603  1.0
  O  O16  1  0.647  0.763  0.103  1.0
  O  O17  1  0.008  0.779  0.881  1.0
  O  O18  1  0.149  0.000  0.105  1.0
  O  O19  1  0.485  0.000  0.892  1.0
  O  O20  1  0.822  0.000  0.608  1.0
  O  O21  1  0.552  0.000  0.387  1.0
  O  O22  1  0.008  0.221  0.881  1.0
  O  O23  1  0.647  0.237  0.103  1.0
  O  O24  1  0.353  0.263  0.603  1.0
  O  O25  1  0.992  0.279  0.381  1.0
[/CIF]
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The compound described by Mg2Mn3O8 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(3), two equivalent O(5), and two equivalent O(6) atoms to form MgO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra, corners with four equivalent Mn(2)O6 octahedra, corners with two equivalent Mg(2)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-55°. In the second Mg site, Mg(2) is bonded to one O(2), one O(4), and two equivalent O(5) atoms to form MgO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Mn(1)O6 octahedra, and corners with six equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-63°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(3), two equivalent O(5), and two equivalent O(6) atoms to form MnO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Mg(2)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form MnO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Mg(2)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(2), one Mn(1), and two equivalent Mn(2) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Mg(2) and two equivalent Mn(2) atoms. In the fifth O site, O(5) is bonded to one Mg(1), one Mg(2), one Mn(1), and one Mn(2) atom to form a mixture of distorted corner and edge-sharing OMg2Mn2 tetrahedra. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Mg(1), one Mn(1), and one Mn(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Mn3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.880
_cell_length_b   5.747
_cell_length_c   9.377
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   263.017
_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
  Mg  Mg0  1  0.815  0.500  0.221  1.0
  Mg  Mg1  1  0.822  0.500  0.815  1.0
  Mg  Mg2  1  0.178  0.000  0.315  1.0
  Mg  Mg3  1  0.185  0.000  0.721  1.0
  Mn  Mn4  1  0.184  0.500  0.498  1.0
  Mn  Mn5  1  0.323  0.740  0.000  1.0
  Mn  Mn6  1  0.677  0.760  0.500  1.0
  Mn  Mn7  1  0.816  0.000  0.998  1.0
  Mn  Mn8  1  0.677  0.240  0.500  1.0
  Mn  Mn9  1  0.323  0.260  0.000  1.0
  O  O10  1  0.178  0.500  0.108  1.0
  O  O11  1  0.851  0.500  0.605  1.0
  O  O12  1  0.515  0.500  0.392  1.0
  O  O13  1  0.448  0.500  0.887  1.0
  O  O14  1  0.992  0.721  0.381  1.0
  O  O15  1  0.353  0.737  0.603  1.0
  O  O16  1  0.647  0.763  0.103  1.0
  O  O17  1  0.008  0.779  0.881  1.0
  O  O18  1  0.149  0.000  0.105  1.0
  O  O19  1  0.485  0.000  0.892  1.0
  O  O20  1  0.822  0.000  0.608  1.0
  O  O21  1  0.552  0.000  0.387  1.0
  O  O22  1  0.008  0.221  0.881  1.0
  O  O23  1  0.647  0.237  0.103  1.0
  O  O24  1  0.353  0.263  0.603  1.0
  O  O25  1  0.992  0.279  0.381  1.0
[/CIF]
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