The material described by Rb2U2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(7) atoms to form distorted RbO6 octahedra that share  a cornercorner with one U(2)O6 octahedra, corners with two equivalent U(3)O6 octahedra, edges with two equivalent Rb(1)O6 octahedra, and edges with four equivalent Rb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-59°. In the second Rb site, Rb(2) is bonded to one O(1), one O(7), two equivalent O(3), and two equivalent O(5) atoms to form distorted RbO6 octahedra that share  a cornercorner with one U(3)O6 octahedra, corners with two equivalent U(2)O6 octahedra, edges with two equivalent Rb(2)O6 octahedra, and edges with four equivalent Rb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-59°. There are three inequivalent U sites. In the first U site, U(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(6), two equivalent O(2), and two equivalent O(4) atoms. In the second U site, U(2) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form UO6 octahedra that share corners with two equivalent Rb(1)O6 octahedra, corners with two equivalent U(3)O6 octahedra, and corners with four equivalent Rb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-59°. In the third U site, U(3) is bonded to two equivalent O(2), two equivalent O(6), and two equivalent O(7) atoms to form UO6 octahedra that share corners with two equivalent Rb(2)O6 octahedra, corners with two equivalent U(2)O6 octahedra, and corners with four equivalent Rb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-59°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Rb(2), two equivalent Rb(1), and one U(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one U(3) and two equivalent U(1) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), two equivalent Rb(2), and one U(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one U(2) and two equivalent U(1) atoms. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), two equivalent Rb(2), and one U(2) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one U(1), one U(2), and one U(3) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Rb(2), two equivalent Rb(1), and one U(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb2U2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.927
_cell_length_b   7.428
_cell_length_c   7.997
_cell_angle_alpha   105.695
_cell_angle_beta   89.695
_cell_angle_gamma   99.135
_symmetry_Int_Tables_number   1
_cell_volume   390.842
_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  0.240  0.487  0.626  1.0
  Rb  Rb1  1  0.263  0.489  0.118  1.0
  Rb  Rb2  1  0.760  0.513  0.374  1.0
  Rb  Rb3  1  0.737  0.511  0.882  1.0
  U  U4  1  0.032  0.994  0.246  1.0
  U  U5  1  0.968  0.006  0.754  1.0
  U  U6  1  0.500  0.000  0.000  1.0
  U  U7  1  0.500  0.000  0.500  1.0
  O  O8  1  0.066  0.257  0.311  1.0
  O  O9  1  0.190  0.017  0.557  1.0
  O  O10  1  0.008  0.269  0.821  1.0
  O  O11  1  0.189  0.019  0.959  1.0
  O  O12  1  0.557  0.266  0.079  1.0
  O  O13  1  0.443  0.734  0.921  1.0
  O  O14  1  0.368  0.985  0.246  1.0
  O  O15  1  0.553  0.267  0.555  1.0
  O  O16  1  0.447  0.733  0.445  1.0
  O  O17  1  0.810  0.983  0.443  1.0
  O  O18  1  0.632  0.015  0.754  1.0
  O  O19  1  0.934  0.743  0.689  1.0
  O  O20  1  0.811  0.981  0.041  1.0
  O  O21  1  0.992  0.731  0.179  1.0
[/CIF]
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The material described by Rb2U2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(7) atoms to form distorted RbO6 octahedra that share  a cornercorner with one U(2)O6 octahedra, corners with two equivalent U(3)O6 octahedra, edges with two equivalent Rb(1)O6 octahedra, and edges with four equivalent Rb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-59°. In the second Rb site, Rb(2) is bonded to one O(1), one O(7), two equivalent O(3), and two equivalent O(5) atoms to form distorted RbO6 octahedra that share  a cornercorner with one U(3)O6 octahedra, corners with two equivalent U(2)O6 octahedra, edges with two equivalent Rb(2)O6 octahedra, and edges with four equivalent Rb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-59°. There are three inequivalent U sites. In the first U site, U(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(6), two equivalent O(2), and two equivalent O(4) atoms. In the second U site, U(2) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form UO6 octahedra that share corners with two equivalent Rb(1)O6 octahedra, corners with two equivalent U(3)O6 octahedra, and corners with four equivalent Rb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-59°. In the third U site, U(3) is bonded to two equivalent O(2), two equivalent O(6), and two equivalent O(7) atoms to form UO6 octahedra that share corners with two equivalent Rb(2)O6 octahedra, corners with two equivalent U(2)O6 octahedra, and corners with four equivalent Rb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-59°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Rb(2), two equivalent Rb(1), and one U(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one U(3) and two equivalent U(1) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), two equivalent Rb(2), and one U(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one U(2) and two equivalent U(1) atoms. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1), two equivalent Rb(2), and one U(2) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one U(1), one U(2), and one U(3) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Rb(2), two equivalent Rb(1), and one U(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb2U2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.927
_cell_length_b   7.428
_cell_length_c   7.997
_cell_angle_alpha   105.695
_cell_angle_beta   89.695
_cell_angle_gamma   99.135
_symmetry_Int_Tables_number   1
_cell_volume   390.842
_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  0.240  0.487  0.626  1.0
  Rb  Rb1  1  0.263  0.489  0.118  1.0
  Rb  Rb2  1  0.760  0.513  0.374  1.0
  Rb  Rb3  1  0.737  0.511  0.882  1.0
  U  U4  1  0.032  0.994  0.246  1.0
  U  U5  1  0.968  0.006  0.754  1.0
  U  U6  1  0.500  0.000  0.000  1.0
  U  U7  1  0.500  0.000  0.500  1.0
  O  O8  1  0.066  0.257  0.311  1.0
  O  O9  1  0.190  0.017  0.557  1.0
  O  O10  1  0.008  0.269  0.821  1.0
  O  O11  1  0.189  0.019  0.959  1.0
  O  O12  1  0.557  0.266  0.079  1.0
  O  O13  1  0.443  0.734  0.921  1.0
  O  O14  1  0.368  0.985  0.246  1.0
  O  O15  1  0.553  0.267  0.555  1.0
  O  O16  1  0.447  0.733  0.445  1.0
  O  O17  1  0.810  0.983  0.443  1.0
  O  O18  1  0.632  0.015  0.754  1.0
  O  O19  1  0.934  0.743  0.689  1.0
  O  O20  1  0.811  0.981  0.041  1.0
  O  O21  1  0.992  0.731  0.179  1.0
[/CIF]
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