The structure described by Rb4Li(Se2O7)2 crystallizes in the monoclinic C2 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 8-coordinate geometry to one O(4), one O(6), two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. In the second Rb site, Rb(2) is bonded in a 7-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(4), and two equivalent O(6) atoms. Li(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with two equivalent Se(1)O4 tetrahedra and corners with two equivalent Se(2)O4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form SeO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra and  a cornercorner with one Se(1)O4 tetrahedra. In the second Se site, Se(2) is bonded to one O(2), one O(4), one O(6), and one O(8) atom to form SeO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra and  a cornercorner with one Se(2)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Rb(2) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent Rb(1), one Li(1), and one Se(2) atom. In the third O site, O(3) is bonded in a distorted water-like geometry to one Rb(2), two equivalent Rb(1), one Li(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Rb(1) and one Se(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Se(2) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to two equivalent Se(1) atoms. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to two equivalent Se(2) atoms. is represented by the CIF file [CIF]
data_Rb4Li(Se2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.520
_cell_length_b   8.520
_cell_length_c   7.626
_cell_angle_alpha   97.821
_cell_angle_beta   97.821
_cell_angle_gamma   57.776
_symmetry_Int_Tables_number   1
_cell_volume   462.623
_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  0.066  0.608  0.319  1.0
  Rb  Rb1  1  0.392  0.934  0.181  1.0
  Rb  Rb2  1  0.874  0.426  0.674  1.0
  Rb  Rb3  1  0.574  0.126  0.826  1.0
  Li  Li4  1  0.495  0.505  0.250  1.0
  Se  Se5  1  0.697  0.122  0.365  1.0
  Se  Se6  1  0.878  0.303  0.135  1.0
  Se  Se7  1  0.327  0.846  0.638  1.0
  Se  Se8  1  0.154  0.673  0.862  1.0
  O  O9  1  0.681  0.242  0.560  1.0
  O  O10  1  0.758  0.319  0.940  1.0
  O  O11  1  0.355  0.705  0.456  1.0
  O  O12  1  0.295  0.645  0.044  1.0
  O  O13  1  0.508  0.260  0.230  1.0
  O  O14  1  0.740  0.492  0.270  1.0
  O  O15  1  0.509  0.773  0.783  1.0
  O  O16  1  0.227  0.491  0.717  1.0
  O  O17  1  0.701  0.924  0.387  1.0
  O  O18  1  0.076  0.299  0.113  1.0
  O  O19  1  0.234  0.064  0.594  1.0
  O  O20  1  0.936  0.766  0.906  1.0
  O  O21  1  0.896  0.104  0.250  1.0
  O  O22  1  0.138  0.862  0.750  1.0
[/CIF]
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The structure described by Rb4Li(Se2O7)2 crystallizes in the monoclinic C2 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 8-coordinate geometry to one O(4), one O(6), two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. In the second Rb site, Rb(2) is bonded in a 7-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(4), and two equivalent O(6) atoms. Li(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with two equivalent Se(1)O4 tetrahedra and corners with two equivalent Se(2)O4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form SeO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra and  a cornercorner with one Se(1)O4 tetrahedra. In the second Se site, Se(2) is bonded to one O(2), one O(4), one O(6), and one O(8) atom to form SeO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra and  a cornercorner with one Se(2)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Rb(2) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent Rb(1), one Li(1), and one Se(2) atom. In the third O site, O(3) is bonded in a distorted water-like geometry to one Rb(2), two equivalent Rb(1), one Li(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Rb(1) and one Se(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Se(2) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to two equivalent Se(1) atoms. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to two equivalent Se(2) atoms. is represented by the CIF file [CIF]
data_Rb4Li(Se2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.520
_cell_length_b   8.520
_cell_length_c   7.626
_cell_angle_alpha   97.821
_cell_angle_beta   97.821
_cell_angle_gamma   57.776
_symmetry_Int_Tables_number   1
_cell_volume   462.623
_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  0.066  0.608  0.319  1.0
  Rb  Rb1  1  0.392  0.934  0.181  1.0
  Rb  Rb2  1  0.874  0.426  0.674  1.0
  Rb  Rb3  1  0.574  0.126  0.826  1.0
  Li  Li4  1  0.495  0.505  0.250  1.0
  Se  Se5  1  0.697  0.122  0.365  1.0
  Se  Se6  1  0.878  0.303  0.135  1.0
  Se  Se7  1  0.327  0.846  0.638  1.0
  Se  Se8  1  0.154  0.673  0.862  1.0
  O  O9  1  0.681  0.242  0.560  1.0
  O  O10  1  0.758  0.319  0.940  1.0
  O  O11  1  0.355  0.705  0.456  1.0
  O  O12  1  0.295  0.645  0.044  1.0
  O  O13  1  0.508  0.260  0.230  1.0
  O  O14  1  0.740  0.492  0.270  1.0
  O  O15  1  0.509  0.773  0.783  1.0
  O  O16  1  0.227  0.491  0.717  1.0
  O  O17  1  0.701  0.924  0.387  1.0
  O  O18  1  0.076  0.299  0.113  1.0
  O  O19  1  0.234  0.064  0.594  1.0
  O  O20  1  0.936  0.766  0.906  1.0
  O  O21  1  0.896  0.104  0.250  1.0
  O  O22  1  0.138  0.862  0.750  1.0
[/CIF]
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