The material structure described by RbFe(SeO4)(SeO3) crystallizes in the trigonal R-3m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to six equivalent O(1) and six equivalent O(3) atoms to form RbO12 cuboctahedra that share edges with six equivalent Rb(1)O12 cuboctahedra, edges with six equivalent Se(1)O4 tetrahedra, and faces with two equivalent Fe(1)O6 octahedra. In the second Rb site, Rb(2) is bonded to twelve equivalent O(2) atoms to form RbO12 cuboctahedra that share edges with six equivalent Rb(2)O12 cuboctahedra and edges with six equivalent Fe(1)O6 octahedra. Fe(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form FeO6 octahedra that share corners with three equivalent Se(1)O4 tetrahedra, edges with three equivalent Rb(2)O12 cuboctahedra, and  a faceface with one Rb(1)O12 cuboctahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(3) and three equivalent O(1) atoms to form SeO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra and edges with three equivalent Rb(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 21°. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Fe(1), and one Se(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Rb(2), one Fe(1), and one Se(2) atom. In the third O site, O(3) is bonded in a single-bond geometry to three equivalent Rb(1) and one Se(1) atom. is represented by the CIF file [CIF]
data_RbFeSe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.348
_cell_length_b   14.348
_cell_length_c   14.348
_cell_angle_alpha   22.182
_cell_angle_beta   22.182
_cell_angle_gamma   22.182
_symmetry_Int_Tables_number   1
_cell_volume   369.201
_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  0.000  0.000  0.000  1.0
  Rb  Rb1  1  0.500  0.500  0.500  1.0
  Fe  Fe2  1  0.099  0.099  0.099  1.0
  Fe  Fe3  1  0.901  0.901  0.901  1.0
  Se  Se4  1  0.386  0.386  0.386  1.0
  Se  Se5  1  0.228  0.228  0.228  1.0
  Se  Se6  1  0.614  0.614  0.614  1.0
  Se  Se7  1  0.772  0.772  0.772  1.0
  O  O8  1  0.234  0.234  0.731  1.0
  O  O9  1  0.049  0.528  0.049  1.0
  O  O10  1  0.951  0.472  0.951  1.0
  O  O11  1  0.951  0.951  0.472  1.0
  O  O12  1  0.049  0.049  0.528  1.0
  O  O13  1  0.269  0.766  0.766  1.0
  O  O14  1  0.472  0.951  0.951  1.0
  O  O15  1  0.653  0.653  0.653  1.0
  O  O16  1  0.731  0.234  0.234  1.0
  O  O17  1  0.766  0.269  0.766  1.0
  O  O18  1  0.234  0.731  0.234  1.0
  O  O19  1  0.528  0.049  0.049  1.0
  O  O20  1  0.347  0.347  0.347  1.0
  O  O21  1  0.766  0.766  0.269  1.0
[/CIF]
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The material structure described by RbFe(SeO4)(SeO3) crystallizes in the trigonal R-3m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to six equivalent O(1) and six equivalent O(3) atoms to form RbO12 cuboctahedra that share edges with six equivalent Rb(1)O12 cuboctahedra, edges with six equivalent Se(1)O4 tetrahedra, and faces with two equivalent Fe(1)O6 octahedra. In the second Rb site, Rb(2) is bonded to twelve equivalent O(2) atoms to form RbO12 cuboctahedra that share edges with six equivalent Rb(2)O12 cuboctahedra and edges with six equivalent Fe(1)O6 octahedra. Fe(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form FeO6 octahedra that share corners with three equivalent Se(1)O4 tetrahedra, edges with three equivalent Rb(2)O12 cuboctahedra, and  a faceface with one Rb(1)O12 cuboctahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(3) and three equivalent O(1) atoms to form SeO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra and edges with three equivalent Rb(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 21°. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Fe(1), and one Se(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent Rb(2), one Fe(1), and one Se(2) atom. In the third O site, O(3) is bonded in a single-bond geometry to three equivalent Rb(1) and one Se(1) atom. is represented by the CIF file [CIF]
data_RbFeSe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.348
_cell_length_b   14.348
_cell_length_c   14.348
_cell_angle_alpha   22.182
_cell_angle_beta   22.182
_cell_angle_gamma   22.182
_symmetry_Int_Tables_number   1
_cell_volume   369.201
_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  0.000  0.000  0.000  1.0
  Rb  Rb1  1  0.500  0.500  0.500  1.0
  Fe  Fe2  1  0.099  0.099  0.099  1.0
  Fe  Fe3  1  0.901  0.901  0.901  1.0
  Se  Se4  1  0.386  0.386  0.386  1.0
  Se  Se5  1  0.228  0.228  0.228  1.0
  Se  Se6  1  0.614  0.614  0.614  1.0
  Se  Se7  1  0.772  0.772  0.772  1.0
  O  O8  1  0.234  0.234  0.731  1.0
  O  O9  1  0.049  0.528  0.049  1.0
  O  O10  1  0.951  0.472  0.951  1.0
  O  O11  1  0.951  0.951  0.472  1.0
  O  O12  1  0.049  0.049  0.528  1.0
  O  O13  1  0.269  0.766  0.766  1.0
  O  O14  1  0.472  0.951  0.951  1.0
  O  O15  1  0.653  0.653  0.653  1.0
  O  O16  1  0.731  0.234  0.234  1.0
  O  O17  1  0.766  0.269  0.766  1.0
  O  O18  1  0.234  0.731  0.234  1.0
  O  O19  1  0.528  0.049  0.049  1.0
  O  O20  1  0.347  0.347  0.347  1.0
  O  O21  1  0.766  0.766  0.269  1.0
[/CIF]
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