The material structure described by RbMgMn4O8 crystallizes in the triclinic P1 space group. Rb(1) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(5), and two equivalent O(7) atoms. Mg(1) is bonded in a distorted see-saw-like geometry to one O(2), one O(4), and two equivalent O(6) atoms. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(6), and two equivalent O(7) atoms to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one Mn(3)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, and edges with two equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-58°. In the second Mn site, Mn(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Mn(4)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. In the third Mn site, Mn(3) is bonded to one O(5), one O(6), two equivalent O(4), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(4)O6 octahedra,  a cornercorner with one Mn(1)O5 trigonal bipyramid, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-58°. In the fourth Mn site, Mn(4) is bonded to one O(7), one O(8), two equivalent O(2), and two equivalent O(3) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Mn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 51-58°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(1), and two equivalent Mn(4) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mn(2) and two equivalent Mn(4) atoms. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(2), and two equivalent Mn(3) atoms. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to two equivalent Rb(1), one Mn(3), and two equivalent Mn(2) atoms. In the sixth O site, O(6) is bonded in a see-saw-like geometry to two equivalent Mg(1), one Mn(1), and one Mn(3) atom. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to two equivalent Rb(1), one Mn(4), and two equivalent Mn(1) atoms. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Rb(1), one Mn(4), and two equivalent Mn(3) atoms. is represented by the CIF file [CIF]
data_RbMgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.567
_cell_length_b   7.567
_cell_length_c   7.867
_cell_angle_alpha   92.641
_cell_angle_beta   156.291
_cell_angle_gamma   93.958
_symmetry_Int_Tables_number   1
_cell_volume   173.852
_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
  Rb  Rb0  1  0.497  0.939  0.455  1.0
  Mg  Mg1  1  0.864  0.205  0.113  1.0
  Mn  Mn2  1  0.876  0.162  0.443  1.0
  Mn  Mn3  1  0.354  0.501  0.162  1.0
  Mn  Mn4  1  0.661  0.526  0.830  1.0
  Mn  Mn5  1  0.225  0.803  0.711  1.0
  O  O6  1  0.823  0.355  0.551  1.0
  O  O7  1  0.831  0.977  0.198  1.0
  O  O8  1  0.591  0.678  0.202  1.0
  O  O9  1  0.065  0.367  0.110  1.0
  O  O10  1  0.853  0.633  0.775  1.0
  O  O11  1  0.364  0.312  0.722  1.0
  O  O12  1  0.241  0.020  0.899  1.0
  O  O13  1  0.230  0.664  0.495  1.0
[/CIF]
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The material structure described by RbMgMn4O8 crystallizes in the triclinic P1 space group. Rb(1) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(5), and two equivalent O(7) atoms. Mg(1) is bonded in a distorted see-saw-like geometry to one O(2), one O(4), and two equivalent O(6) atoms. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(6), and two equivalent O(7) atoms to form distorted MnO5 trigonal bipyramids that share  a cornercorner with one Mn(3)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, and edges with two equivalent Mn(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-58°. In the second Mn site, Mn(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Mn(4)O6 octahedra, corners with two equivalent Mn(1)O5 trigonal bipyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. In the third Mn site, Mn(3) is bonded to one O(5), one O(6), two equivalent O(4), and two equivalent O(8) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(4)O6 octahedra,  a cornercorner with one Mn(1)O5 trigonal bipyramid, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-58°. In the fourth Mn site, Mn(4) is bonded to one O(7), one O(8), two equivalent O(2), and two equivalent O(3) atoms to form distorted MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Mn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 51-58°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(1), and two equivalent Mn(4) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mn(2) and two equivalent Mn(4) atoms. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(2), and two equivalent Mn(3) atoms. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to two equivalent Rb(1), one Mn(3), and two equivalent Mn(2) atoms. In the sixth O site, O(6) is bonded in a see-saw-like geometry to two equivalent Mg(1), one Mn(1), and one Mn(3) atom. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to two equivalent Rb(1), one Mn(4), and two equivalent Mn(1) atoms. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Rb(1), one Mn(4), and two equivalent Mn(3) atoms. is represented by the CIF file [CIF]
data_RbMgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.567
_cell_length_b   7.567
_cell_length_c   7.867
_cell_angle_alpha   92.641
_cell_angle_beta   156.291
_cell_angle_gamma   93.958
_symmetry_Int_Tables_number   1
_cell_volume   173.852
_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
  Rb  Rb0  1  0.497  0.939  0.455  1.0
  Mg  Mg1  1  0.864  0.205  0.113  1.0
  Mn  Mn2  1  0.876  0.162  0.443  1.0
  Mn  Mn3  1  0.354  0.501  0.162  1.0
  Mn  Mn4  1  0.661  0.526  0.830  1.0
  Mn  Mn5  1  0.225  0.803  0.711  1.0
  O  O6  1  0.823  0.355  0.551  1.0
  O  O7  1  0.831  0.977  0.198  1.0
  O  O8  1  0.591  0.678  0.202  1.0
  O  O9  1  0.065  0.367  0.110  1.0
  O  O10  1  0.853  0.633  0.775  1.0
  O  O11  1  0.364  0.312  0.722  1.0
  O  O12  1  0.241  0.020  0.899  1.0
  O  O13  1  0.230  0.664  0.495  1.0
[/CIF]
.