The structure described by Rb2NaMnO4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one O(2), two equivalent O(1), and three equivalent O(3) atoms. In the second Rb site, Rb(2) is bonded to one O(3), two equivalent O(1), and four equivalent O(2) atoms to form distorted RbO7 pentagonal bipyramids that share corners with four equivalent Rb(2)O7 pentagonal bipyramids,  a cornercorner with one Mn(1)O4 tetrahedra, corners with three equivalent Na(1)O5 trigonal bipyramids, edges with four equivalent Rb(2)O7 pentagonal bipyramids, edges with three equivalent Mn(1)O4 tetrahedra, and  an edgeedge with one Na(1)O5 trigonal bipyramid. Na(1) is bonded to one O(3) and four equivalent O(1) atoms to form distorted NaO5 trigonal bipyramids that share corners with three equivalent Rb(2)O7 pentagonal bipyramids, corners with three equivalent Mn(1)O4 tetrahedra,  an edgeedge with one Rb(2)O7 pentagonal bipyramid,  an edgeedge with one Mn(1)O4 tetrahedra, and edges with two equivalent Na(1)O5 trigonal bipyramids. Mn(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form MnO4 tetrahedra that share  a cornercorner with one Rb(2)O7 pentagonal bipyramid, corners with three equivalent Na(1)O5 trigonal bipyramids, edges with three equivalent Rb(2)O7 pentagonal bipyramids, and  an edgeedge with one Na(1)O5 trigonal bipyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Rb(1), one Rb(2), two equivalent Na(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), four equivalent Rb(2), and one Mn(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Rb(2), three equivalent Rb(1), one Na(1), and one Mn(1) atom. is represented by the CIF file [CIF]
data_Rb2NaMnO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.957
_cell_length_b   5.899
_cell_length_c   7.855
_cell_angle_alpha   87.309
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   275.719
_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
  Rb  Rb0  1  0.750  0.128  0.826  1.0
  Rb  Rb1  1  0.250  0.872  0.174  1.0
  Rb  Rb2  1  0.250  0.306  0.486  1.0
  Rb  Rb3  1  0.750  0.694  0.514  1.0
  Na  Na4  1  0.750  0.617  0.031  1.0
  Na  Na5  1  0.250  0.383  0.969  1.0
  Mn  Mn6  1  0.250  0.803  0.745  1.0
  Mn  Mn7  1  0.750  0.197  0.255  1.0
  O  O8  1  0.521  0.337  0.174  1.0
  O  O9  1  0.021  0.663  0.826  1.0
  O  O10  1  0.479  0.663  0.826  1.0
  O  O11  1  0.979  0.337  0.174  1.0
  O  O12  1  0.750  0.199  0.470  1.0
  O  O13  1  0.750  0.928  0.188  1.0
  O  O14  1  0.250  0.801  0.530  1.0
  O  O15  1  0.250  0.072  0.812  1.0
[/CIF]
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The structure described by Rb2NaMnO4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one O(2), two equivalent O(1), and three equivalent O(3) atoms. In the second Rb site, Rb(2) is bonded to one O(3), two equivalent O(1), and four equivalent O(2) atoms to form distorted RbO7 pentagonal bipyramids that share corners with four equivalent Rb(2)O7 pentagonal bipyramids,  a cornercorner with one Mn(1)O4 tetrahedra, corners with three equivalent Na(1)O5 trigonal bipyramids, edges with four equivalent Rb(2)O7 pentagonal bipyramids, edges with three equivalent Mn(1)O4 tetrahedra, and  an edgeedge with one Na(1)O5 trigonal bipyramid. Na(1) is bonded to one O(3) and four equivalent O(1) atoms to form distorted NaO5 trigonal bipyramids that share corners with three equivalent Rb(2)O7 pentagonal bipyramids, corners with three equivalent Mn(1)O4 tetrahedra,  an edgeedge with one Rb(2)O7 pentagonal bipyramid,  an edgeedge with one Mn(1)O4 tetrahedra, and edges with two equivalent Na(1)O5 trigonal bipyramids. Mn(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form MnO4 tetrahedra that share  a cornercorner with one Rb(2)O7 pentagonal bipyramid, corners with three equivalent Na(1)O5 trigonal bipyramids, edges with three equivalent Rb(2)O7 pentagonal bipyramids, and  an edgeedge with one Na(1)O5 trigonal bipyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Rb(1), one Rb(2), two equivalent Na(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), four equivalent Rb(2), and one Mn(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Rb(2), three equivalent Rb(1), one Na(1), and one Mn(1) atom. is represented by the CIF file [CIF]
data_Rb2NaMnO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.957
_cell_length_b   5.899
_cell_length_c   7.855
_cell_angle_alpha   87.309
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   275.719
_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
  Rb  Rb0  1  0.750  0.128  0.826  1.0
  Rb  Rb1  1  0.250  0.872  0.174  1.0
  Rb  Rb2  1  0.250  0.306  0.486  1.0
  Rb  Rb3  1  0.750  0.694  0.514  1.0
  Na  Na4  1  0.750  0.617  0.031  1.0
  Na  Na5  1  0.250  0.383  0.969  1.0
  Mn  Mn6  1  0.250  0.803  0.745  1.0
  Mn  Mn7  1  0.750  0.197  0.255  1.0
  O  O8  1  0.521  0.337  0.174  1.0
  O  O9  1  0.021  0.663  0.826  1.0
  O  O10  1  0.479  0.663  0.826  1.0
  O  O11  1  0.979  0.337  0.174  1.0
  O  O12  1  0.750  0.199  0.470  1.0
  O  O13  1  0.750  0.928  0.188  1.0
  O  O14  1  0.250  0.801  0.530  1.0
  O  O15  1  0.250  0.072  0.812  1.0
[/CIF]
.