The material described by RbNaUSi2O9 crystallizes in the triclinic P-1 space group. Rb(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(5), one O(6), one O(9), and two equivalent O(2) atoms. Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(9) atom. There are two inequivalent U sites. In the first U site, U(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form UO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. In the second U site, U(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(8) atoms to form UO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one U(1)O6 octahedra,  a cornercorner with one U(2)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-47°. In the second Si site, Si(2) is bonded to one O(3), one O(6), 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 U(2)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-47°. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Rb(1), one Na(1), and one U(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one Na(1), and one U(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Rb(1), one U(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one U(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Rb(1), one Na(1), one U(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Rb(1), one Si(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Na(1), one Si(1), and one Si(2) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one U(2) and one Si(2) atom. In the ninth O site, O(9) is bonded in a water-like geometry to one Rb(1) and one Na(1) atom. is represented by the CIF card [CIF]
data_RbNaUSi2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.459
_cell_length_b   7.938
_cell_length_c   8.251
_cell_angle_alpha   78.238
_cell_angle_beta   74.831
_cell_angle_gamma   84.587
_symmetry_Int_Tables_number   1
_cell_volume   461.219
_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  0.898  0.551  0.791  1.0
  Rb  Rb1  1  0.102  0.449  0.209  1.0
  Na  Na2  1  0.615  0.191  0.244  1.0
  Na  Na3  1  0.385  0.809  0.756  1.0
  U  U4  1  0.500  0.500  0.500  1.0
  U  U5  1  0.000  0.000  0.000  1.0
  Si  Si6  1  0.788  0.861  0.438  1.0
  Si  Si7  1  0.212  0.139  0.562  1.0
  Si  Si8  1  0.212  0.859  0.349  1.0
  Si  Si9  1  0.788  0.141  0.651  1.0
  O  O10  1  0.690  0.455  0.314  1.0
  O  O11  1  0.310  0.545  0.686  1.0
  O  O12  1  0.926  0.229  0.021  1.0
  O  O13  1  0.074  0.771  0.979  1.0
  O  O14  1  0.650  0.311  0.672  1.0
  O  O15  1  0.350  0.689  0.328  1.0
  O  O16  1  0.781  0.921  0.240  1.0
  O  O17  1  0.219  0.079  0.760  1.0
  O  O18  1  0.649  0.710  0.549  1.0
  O  O19  1  0.351  0.290  0.451  1.0
  O  O20  1  1.000  0.791  0.455  1.0
  O  O21  1  0.000  0.209  0.545  1.0
  O  O22  1  0.280  0.966  0.473  1.0
  O  O23  1  0.720  0.034  0.527  1.0
  O  O24  1  0.807  0.012  0.827  1.0
  O  O25  1  0.193  0.988  0.173  1.0
  O  O26  1  0.564  0.745  0.972  1.0
  O  O27  1  0.436  0.255  0.028  1.0
[/CIF]
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The material described by RbNaUSi2O9 crystallizes in the triclinic P-1 space group. Rb(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(5), one O(6), one O(9), and two equivalent O(2) atoms. Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(9) atom. There are two inequivalent U sites. In the first U site, U(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form UO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. In the second U site, U(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(8) atoms to form UO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one U(1)O6 octahedra,  a cornercorner with one U(2)O6 octahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-47°. In the second Si site, Si(2) is bonded to one O(3), one O(6), 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 U(2)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-47°. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Rb(1), one Na(1), and one U(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Rb(1), one Na(1), and one U(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Rb(1), one U(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one U(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Rb(1), one Na(1), one U(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Rb(1), one Si(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Na(1), one Si(1), and one Si(2) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one U(2) and one Si(2) atom. In the ninth O site, O(9) is bonded in a water-like geometry to one Rb(1) and one Na(1) atom. is represented by the CIF card [CIF]
data_RbNaUSi2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.459
_cell_length_b   7.938
_cell_length_c   8.251
_cell_angle_alpha   78.238
_cell_angle_beta   74.831
_cell_angle_gamma   84.587
_symmetry_Int_Tables_number   1
_cell_volume   461.219
_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  0.898  0.551  0.791  1.0
  Rb  Rb1  1  0.102  0.449  0.209  1.0
  Na  Na2  1  0.615  0.191  0.244  1.0
  Na  Na3  1  0.385  0.809  0.756  1.0
  U  U4  1  0.500  0.500  0.500  1.0
  U  U5  1  0.000  0.000  0.000  1.0
  Si  Si6  1  0.788  0.861  0.438  1.0
  Si  Si7  1  0.212  0.139  0.562  1.0
  Si  Si8  1  0.212  0.859  0.349  1.0
  Si  Si9  1  0.788  0.141  0.651  1.0
  O  O10  1  0.690  0.455  0.314  1.0
  O  O11  1  0.310  0.545  0.686  1.0
  O  O12  1  0.926  0.229  0.021  1.0
  O  O13  1  0.074  0.771  0.979  1.0
  O  O14  1  0.650  0.311  0.672  1.0
  O  O15  1  0.350  0.689  0.328  1.0
  O  O16  1  0.781  0.921  0.240  1.0
  O  O17  1  0.219  0.079  0.760  1.0
  O  O18  1  0.649  0.710  0.549  1.0
  O  O19  1  0.351  0.290  0.451  1.0
  O  O20  1  1.000  0.791  0.455  1.0
  O  O21  1  0.000  0.209  0.545  1.0
  O  O22  1  0.280  0.966  0.473  1.0
  O  O23  1  0.720  0.034  0.527  1.0
  O  O24  1  0.807  0.012  0.827  1.0
  O  O25  1  0.193  0.988  0.173  1.0
  O  O26  1  0.564  0.745  0.972  1.0
  O  O27  1  0.436  0.255  0.028  1.0
[/CIF]
.