The crystal structure described by Rb8Fe2O7 crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 4-coordinate geometry to one O(2), one O(3), and two equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the third Rb site, Rb(3) is bonded in a 4-coordinate geometry to one O(2), one O(3), and two equivalent O(1) atoms. In the fourth Rb site, Rb(4) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(2), and two equivalent O(3) atoms. Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing FeO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Rb(2), two equivalent Rb(1), two equivalent Rb(3), and one Fe(1) atom to form distorted ORb5Fe octahedra that share  an edgeedge with one O(4)Rb4Fe2 octahedra and edges with two equivalent O(1)Rb5Fe octahedra. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Rb(1), one Rb(2), one Rb(3), two equivalent Rb(4), and one Fe(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Rb(1), one Rb(2), one Rb(3), two equivalent Rb(4), and one Fe(1) atom. In the fourth O site, O(4) is bonded to two equivalent Rb(2), two equivalent Rb(4), and two equivalent Fe(1) atoms to form distorted edge-sharing ORb4Fe2 octahedra. is represented by the CIF card [CIF]
data_Rb8Fe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   17.409
_cell_length_b   6.910
_cell_length_c   6.973
_cell_angle_alpha   61.043
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   733.957
_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  0.711  0.551  0.236  1.0
  Rb  Rb1  1  0.580  0.005  0.639  1.0
  Rb  Rb2  1  0.789  0.051  0.236  1.0
  Rb  Rb3  1  0.289  0.449  0.764  1.0
  Rb  Rb4  1  0.690  0.454  0.781  1.0
  Rb  Rb5  1  0.420  0.995  0.361  1.0
  Rb  Rb6  1  0.310  0.546  0.219  1.0
  Rb  Rb7  1  0.505  0.542  0.229  1.0
  Rb  Rb8  1  0.810  0.954  0.781  1.0
  Rb  Rb9  1  0.995  0.042  0.229  1.0
  Rb  Rb10  1  0.080  0.495  0.361  1.0
  Rb  Rb11  1  0.005  0.958  0.771  1.0
  Rb  Rb12  1  0.495  0.458  0.771  1.0
  Rb  Rb13  1  0.920  0.505  0.639  1.0
  Rb  Rb14  1  0.190  0.046  0.219  1.0
  Rb  Rb15  1  0.211  0.949  0.764  1.0
  Fe  Fe16  1  0.097  0.500  0.857  1.0
  Fe  Fe17  1  0.403  0.000  0.857  1.0
  Fe  Fe18  1  0.597  1.000  0.143  1.0
  Fe  Fe19  1  0.903  0.500  0.143  1.0
  O  O20  1  0.323  0.003  0.042  1.0
  O  O21  1  0.399  0.257  0.580  1.0
  O  O22  1  0.899  0.243  0.420  1.0
  O  O23  1  0.101  0.757  0.580  1.0
  O  O24  1  0.177  0.503  0.042  1.0
  O  O25  1  0.395  0.740  0.833  1.0
  O  O26  1  0.895  0.760  0.167  1.0
  O  O27  1  0.601  0.743  0.420  1.0
  O  O28  1  0.000  0.500  0.000  1.0
  O  O29  1  0.605  0.260  0.167  1.0
  O  O30  1  0.677  0.997  0.958  1.0
  O  O31  1  0.823  0.497  0.958  1.0
  O  O32  1  0.500  0.000  0.000  1.0
  O  O33  1  0.105  0.240  0.833  1.0
[/CIF]
.
The crystal structure described by Rb8Fe2O7 crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 4-coordinate geometry to one O(2), one O(3), and two equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the third Rb site, Rb(3) is bonded in a 4-coordinate geometry to one O(2), one O(3), and two equivalent O(1) atoms. In the fourth Rb site, Rb(4) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(2), and two equivalent O(3) atoms. Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing FeO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Rb(2), two equivalent Rb(1), two equivalent Rb(3), and one Fe(1) atom to form distorted ORb5Fe octahedra that share  an edgeedge with one O(4)Rb4Fe2 octahedra and edges with two equivalent O(1)Rb5Fe octahedra. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Rb(1), one Rb(2), one Rb(3), two equivalent Rb(4), and one Fe(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Rb(1), one Rb(2), one Rb(3), two equivalent Rb(4), and one Fe(1) atom. In the fourth O site, O(4) is bonded to two equivalent Rb(2), two equivalent Rb(4), and two equivalent Fe(1) atoms to form distorted edge-sharing ORb4Fe2 octahedra. is represented by the CIF card [CIF]
data_Rb8Fe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   17.409
_cell_length_b   6.910
_cell_length_c   6.973
_cell_angle_alpha   61.043
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   733.957
_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  0.711  0.551  0.236  1.0
  Rb  Rb1  1  0.580  0.005  0.639  1.0
  Rb  Rb2  1  0.789  0.051  0.236  1.0
  Rb  Rb3  1  0.289  0.449  0.764  1.0
  Rb  Rb4  1  0.690  0.454  0.781  1.0
  Rb  Rb5  1  0.420  0.995  0.361  1.0
  Rb  Rb6  1  0.310  0.546  0.219  1.0
  Rb  Rb7  1  0.505  0.542  0.229  1.0
  Rb  Rb8  1  0.810  0.954  0.781  1.0
  Rb  Rb9  1  0.995  0.042  0.229  1.0
  Rb  Rb10  1  0.080  0.495  0.361  1.0
  Rb  Rb11  1  0.005  0.958  0.771  1.0
  Rb  Rb12  1  0.495  0.458  0.771  1.0
  Rb  Rb13  1  0.920  0.505  0.639  1.0
  Rb  Rb14  1  0.190  0.046  0.219  1.0
  Rb  Rb15  1  0.211  0.949  0.764  1.0
  Fe  Fe16  1  0.097  0.500  0.857  1.0
  Fe  Fe17  1  0.403  0.000  0.857  1.0
  Fe  Fe18  1  0.597  1.000  0.143  1.0
  Fe  Fe19  1  0.903  0.500  0.143  1.0
  O  O20  1  0.323  0.003  0.042  1.0
  O  O21  1  0.399  0.257  0.580  1.0
  O  O22  1  0.899  0.243  0.420  1.0
  O  O23  1  0.101  0.757  0.580  1.0
  O  O24  1  0.177  0.503  0.042  1.0
  O  O25  1  0.395  0.740  0.833  1.0
  O  O26  1  0.895  0.760  0.167  1.0
  O  O27  1  0.601  0.743  0.420  1.0
  O  O28  1  0.000  0.500  0.000  1.0
  O  O29  1  0.605  0.260  0.167  1.0
  O  O30  1  0.677  0.997  0.958  1.0
  O  O31  1  0.823  0.497  0.958  1.0
  O  O32  1  0.500  0.000  0.000  1.0
  O  O33  1  0.105  0.240  0.833  1.0
[/CIF]
.