The structure described by Rb2U(SiO3)4 crystallizes in the triclinic P-1 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one O(10), one O(12), one O(2), one O(4), one O(5), and two equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(6), one O(7), one O(8), and one O(9) atom. U(1) is bonded to one O(1), one O(11), one O(12), one O(3), one O(4), and one O(5) atom to form UO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(11), one O(6), one O(8), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one U(1)O6 octahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 40°. In the second Si site, Si(2) is bonded to one O(2), one O(6), one O(7), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(10), one O(2), one O(3), and one O(5) atom to form SiO4 tetrahedra that share corners with two equivalent U(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-40°. In the fourth Si site, Si(4) is bonded to one O(1), one O(10), one O(7), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one U(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one U(1), and one Si(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Rb(1), one Si(2), and one Si(3) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Rb(2), one U(1), and one Si(3) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), and one U(1) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Rb(1), one U(1), and one Si(3) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Rb(2), one Si(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Rb(2), one Si(2), and one Si(4) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Rb(2), one Si(1), and one Si(4) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Rb(2), one Si(1), and one Si(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Rb(1), one Si(3), and one Si(4) atom. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Rb(2), one U(1), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), and one U(1) atom. is represented by the CIF file [CIF]
data_Rb2U(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.916
_cell_length_b   8.495
_cell_length_c   11.376
_cell_angle_alpha   107.003
_cell_angle_beta   88.788
_cell_angle_gamma   102.736
_symmetry_Int_Tables_number   1
_cell_volume   622.713
_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  0.196  0.310  0.995  1.0
  Rb  Rb1  1  0.823  0.730  0.646  1.0
  Rb  Rb2  1  0.804  0.690  0.005  1.0
  Rb  Rb3  1  0.177  0.270  0.354  1.0
  U  U4  1  0.325  0.717  0.826  1.0
  U  U5  1  0.675  0.283  0.174  1.0
  Si  Si6  1  0.301  0.757  0.516  1.0
  Si  Si7  1  0.325  0.138  0.625  1.0
  Si  Si8  1  0.382  0.868  0.167  1.0
  Si  Si9  1  0.030  0.678  0.288  1.0
  Si  Si10  1  0.970  0.322  0.712  1.0
  Si  Si11  1  0.699  0.243  0.484  1.0
  Si  Si12  1  0.675  0.862  0.375  1.0
  Si  Si13  1  0.618  0.132  0.833  1.0
  O  O14  1  0.060  0.495  0.818  1.0
  O  O15  1  0.557  0.826  0.245  1.0
  O  O16  1  0.425  0.069  0.181  1.0
  O  O17  1  0.940  0.505  0.182  1.0
  O  O18  1  0.575  0.931  0.819  1.0
  O  O19  1  0.492  0.417  0.203  1.0
  O  O20  1  0.377  0.749  0.027  1.0
  O  O21  1  0.467  0.202  0.524  1.0
  O  O22  1  0.854  0.765  0.359  1.0
  O  O23  1  0.840  0.358  0.607  1.0
  O  O24  1  0.227  0.936  0.566  1.0
  O  O25  1  0.773  0.064  0.434  1.0
  O  O26  1  0.623  0.251  0.973  1.0
  O  O27  1  0.146  0.235  0.641  1.0
  O  O28  1  0.443  0.174  0.755  1.0
  O  O29  1  0.832  0.181  0.769  1.0
  O  O30  1  0.722  0.340  0.381  1.0
  O  O31  1  0.533  0.798  0.476  1.0
  O  O32  1  0.856  0.144  0.142  1.0
  O  O33  1  0.160  0.642  0.393  1.0
  O  O34  1  0.144  0.856  0.858  1.0
  O  O35  1  0.508  0.583  0.797  1.0
  O  O36  1  0.168  0.819  0.231  1.0
  O  O37  1  0.278  0.660  0.619  1.0
[/CIF]
.
The structure described by Rb2U(SiO3)4 crystallizes in the triclinic P-1 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one O(10), one O(12), one O(2), one O(4), one O(5), and two equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(6), one O(7), one O(8), and one O(9) atom. U(1) is bonded to one O(1), one O(11), one O(12), one O(3), one O(4), and one O(5) atom to form UO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(11), one O(6), one O(8), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one U(1)O6 octahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 40°. In the second Si site, Si(2) is bonded to one O(2), one O(6), one O(7), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(10), one O(2), one O(3), and one O(5) atom to form SiO4 tetrahedra that share corners with two equivalent U(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-40°. In the fourth Si site, Si(4) is bonded to one O(1), one O(10), one O(7), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one U(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one U(1), and one Si(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Rb(1), one Si(2), and one Si(3) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Rb(2), one U(1), and one Si(3) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), and one U(1) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Rb(1), one U(1), and one Si(3) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Rb(2), one Si(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Rb(2), one Si(2), and one Si(4) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Rb(2), one Si(1), and one Si(4) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Rb(2), one Si(1), and one Si(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Rb(1), one Si(3), and one Si(4) atom. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Rb(2), one U(1), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), and one U(1) atom. is represented by the CIF file [CIF]
data_Rb2U(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.916
_cell_length_b   8.495
_cell_length_c   11.376
_cell_angle_alpha   107.003
_cell_angle_beta   88.788
_cell_angle_gamma   102.736
_symmetry_Int_Tables_number   1
_cell_volume   622.713
_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  0.196  0.310  0.995  1.0
  Rb  Rb1  1  0.823  0.730  0.646  1.0
  Rb  Rb2  1  0.804  0.690  0.005  1.0
  Rb  Rb3  1  0.177  0.270  0.354  1.0
  U  U4  1  0.325  0.717  0.826  1.0
  U  U5  1  0.675  0.283  0.174  1.0
  Si  Si6  1  0.301  0.757  0.516  1.0
  Si  Si7  1  0.325  0.138  0.625  1.0
  Si  Si8  1  0.382  0.868  0.167  1.0
  Si  Si9  1  0.030  0.678  0.288  1.0
  Si  Si10  1  0.970  0.322  0.712  1.0
  Si  Si11  1  0.699  0.243  0.484  1.0
  Si  Si12  1  0.675  0.862  0.375  1.0
  Si  Si13  1  0.618  0.132  0.833  1.0
  O  O14  1  0.060  0.495  0.818  1.0
  O  O15  1  0.557  0.826  0.245  1.0
  O  O16  1  0.425  0.069  0.181  1.0
  O  O17  1  0.940  0.505  0.182  1.0
  O  O18  1  0.575  0.931  0.819  1.0
  O  O19  1  0.492  0.417  0.203  1.0
  O  O20  1  0.377  0.749  0.027  1.0
  O  O21  1  0.467  0.202  0.524  1.0
  O  O22  1  0.854  0.765  0.359  1.0
  O  O23  1  0.840  0.358  0.607  1.0
  O  O24  1  0.227  0.936  0.566  1.0
  O  O25  1  0.773  0.064  0.434  1.0
  O  O26  1  0.623  0.251  0.973  1.0
  O  O27  1  0.146  0.235  0.641  1.0
  O  O28  1  0.443  0.174  0.755  1.0
  O  O29  1  0.832  0.181  0.769  1.0
  O  O30  1  0.722  0.340  0.381  1.0
  O  O31  1  0.533  0.798  0.476  1.0
  O  O32  1  0.856  0.144  0.142  1.0
  O  O33  1  0.160  0.642  0.393  1.0
  O  O34  1  0.144  0.856  0.858  1.0
  O  O35  1  0.508  0.583  0.797  1.0
  O  O36  1  0.168  0.819  0.231  1.0
  O  O37  1  0.278  0.660  0.619  1.0
[/CIF]
.