The material described by Na4Mn2O5 crystallizes in the orthorhombic Fddd space group. Na(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO5 trigonal bipyramids that share corners with four equivalent Mn(1)O5 square pyramids, corners with five equivalent Na(1)O5 trigonal bipyramids, edges with three equivalent Mn(1)O5 square pyramids, and edges with five equivalent Na(1)O5 trigonal bipyramids. Mn(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO5 square pyramids that share  a cornercorner with one Mn(1)O5 square pyramid, corners with eight equivalent Na(1)O5 trigonal bipyramids, edges with two equivalent Mn(1)O5 square pyramids, and edges with six equivalent Na(1)O5 trigonal bipyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Na(1) and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded to four equivalent Na(1) and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 16-23°. In the third O site, O(3) is bonded to four equivalent Na(1) and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-23°. is represented by the CIF card [CIF]
data_Na4Mn2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.791
_cell_length_b   10.158
_cell_length_c   5.441
_cell_angle_alpha   81.501
_cell_angle_beta   68.586
_cell_angle_gamma   29.924
_symmetry_Int_Tables_number   1
_cell_volume   258.081
_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
  Na  Na0  1  0.658  0.162  0.341  1.0
  Na  Na1  1  0.087  0.593  0.412  1.0
  Na  Na2  1  0.342  0.838  0.658  1.0
  Na  Na3  1  0.163  0.657  0.838  1.0
  Na  Na4  1  0.592  0.088  0.909  1.0
  Na  Na5  1  0.412  0.908  0.088  1.0
  Na  Na6  1  0.908  0.412  0.592  1.0
  Na  Na7  1  0.838  0.342  0.162  1.0
  Mn  Mn8  1  0.972  0.528  0.972  1.0
  Mn  Mn9  1  0.722  0.278  0.722  1.0
  Mn  Mn10  1  0.278  0.722  0.278  1.0
  Mn  Mn11  1  0.528  0.972  0.528  1.0
  O  O12  1  0.750  0.750  0.750  1.0
  O  O13  1  0.316  0.316  0.684  1.0
  O  O14  1  0.066  0.066  0.434  1.0
  O  O15  1  0.434  0.434  0.066  1.0
  O  O16  1  0.184  0.184  0.816  1.0
  O  O17  1  0.816  0.816  0.184  1.0
  O  O18  1  0.684  0.684  0.316  1.0
  O  O19  1  0.934  0.934  0.566  1.0
  O  O20  1  0.500  0.500  0.500  1.0
  O  O21  1  0.566  0.566  0.934  1.0
[/CIF]
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The material described by Na4Mn2O5 crystallizes in the orthorhombic Fddd space group. Na(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO5 trigonal bipyramids that share corners with four equivalent Mn(1)O5 square pyramids, corners with five equivalent Na(1)O5 trigonal bipyramids, edges with three equivalent Mn(1)O5 square pyramids, and edges with five equivalent Na(1)O5 trigonal bipyramids. Mn(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO5 square pyramids that share  a cornercorner with one Mn(1)O5 square pyramid, corners with eight equivalent Na(1)O5 trigonal bipyramids, edges with two equivalent Mn(1)O5 square pyramids, and edges with six equivalent Na(1)O5 trigonal bipyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Na(1) and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded to four equivalent Na(1) and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 16-23°. In the third O site, O(3) is bonded to four equivalent Na(1) and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-23°. is represented by the CIF card [CIF]
data_Na4Mn2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.791
_cell_length_b   10.158
_cell_length_c   5.441
_cell_angle_alpha   81.501
_cell_angle_beta   68.586
_cell_angle_gamma   29.924
_symmetry_Int_Tables_number   1
_cell_volume   258.081
_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
  Na  Na0  1  0.658  0.162  0.341  1.0
  Na  Na1  1  0.087  0.593  0.412  1.0
  Na  Na2  1  0.342  0.838  0.658  1.0
  Na  Na3  1  0.163  0.657  0.838  1.0
  Na  Na4  1  0.592  0.088  0.909  1.0
  Na  Na5  1  0.412  0.908  0.088  1.0
  Na  Na6  1  0.908  0.412  0.592  1.0
  Na  Na7  1  0.838  0.342  0.162  1.0
  Mn  Mn8  1  0.972  0.528  0.972  1.0
  Mn  Mn9  1  0.722  0.278  0.722  1.0
  Mn  Mn10  1  0.278  0.722  0.278  1.0
  Mn  Mn11  1  0.528  0.972  0.528  1.0
  O  O12  1  0.750  0.750  0.750  1.0
  O  O13  1  0.316  0.316  0.684  1.0
  O  O14  1  0.066  0.066  0.434  1.0
  O  O15  1  0.434  0.434  0.066  1.0
  O  O16  1  0.184  0.184  0.816  1.0
  O  O17  1  0.816  0.816  0.184  1.0
  O  O18  1  0.684  0.684  0.316  1.0
  O  O19  1  0.934  0.934  0.566  1.0
  O  O20  1  0.500  0.500  0.500  1.0
  O  O21  1  0.566  0.566  0.934  1.0
[/CIF]
.