The material described by CsRbSO4 crystallizes in the trigonal P3m1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to three equivalent O(1), three equivalent O(2), three equivalent O(3), and three equivalent O(4) atoms to form distorted CsO12 cuboctahedra that share edges with six equivalent Cs(1)O12 cuboctahedra, edges with three equivalent S(1)O4 tetrahedra, edges with three equivalent S(2)O4 tetrahedra, and faces with two equivalent Rb(2)O6 octahedra. In the second Cs site, Cs(2) is bonded in a 10-coordinate geometry to one O(2), three equivalent O(3), and six equivalent O(1) atoms. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one O(4) and six equivalent O(3) atoms. In the second Rb site, Rb(2) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form RbO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra, corners with three equivalent S(2)O4 tetrahedra, and faces with two equivalent Cs(1)O12 cuboctahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(2) and three equivalent O(3) atoms to form SO4 tetrahedra that share corners with three equivalent Rb(2)O6 octahedra and edges with three equivalent Cs(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 17°. In the second S site, S(2) is bonded to one O(4) and three equivalent O(1) atoms to form SO4 tetrahedra that share corners with three equivalent Rb(2)O6 octahedra and edges with three equivalent Cs(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 17°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Cs(1), two equivalent Cs(2), one Rb(2), and one S(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Cs(2), three equivalent Cs(1), and one S(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cs(1), one Cs(2), one Rb(2), two equivalent Rb(1), and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to three equivalent Cs(1), one Rb(1), and one S(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CsRbSO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.301
_cell_length_b   6.301
_cell_length_c   8.272
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   284.419
_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
  Cs  Cs0  1  0.000  0.000  0.687  1.0
  Cs  Cs1  1  0.667  0.333  0.378  1.0
  Rb  Rb2  1  0.333  0.667  0.996  1.0
  Rb  Rb3  1  0.000  0.000  0.185  1.0
  S  S4  1  0.667  0.333  0.915  1.0
  S  S5  1  0.333  0.667  0.454  1.0
  O  O6  1  0.204  0.408  0.391  1.0
  O  O7  1  0.204  0.796  0.391  1.0
  O  O8  1  0.592  0.796  0.391  1.0
  O  O9  1  0.667  0.333  0.737  1.0
  O  O10  1  0.796  0.592  0.978  1.0
  O  O11  1  0.796  0.204  0.978  1.0
  O  O12  1  0.408  0.204  0.978  1.0
  O  O13  1  0.333  0.667  0.633  1.0
[/CIF]
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The material described by CsRbSO4 crystallizes in the trigonal P3m1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to three equivalent O(1), three equivalent O(2), three equivalent O(3), and three equivalent O(4) atoms to form distorted CsO12 cuboctahedra that share edges with six equivalent Cs(1)O12 cuboctahedra, edges with three equivalent S(1)O4 tetrahedra, edges with three equivalent S(2)O4 tetrahedra, and faces with two equivalent Rb(2)O6 octahedra. In the second Cs site, Cs(2) is bonded in a 10-coordinate geometry to one O(2), three equivalent O(3), and six equivalent O(1) atoms. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one O(4) and six equivalent O(3) atoms. In the second Rb site, Rb(2) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form RbO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra, corners with three equivalent S(2)O4 tetrahedra, and faces with two equivalent Cs(1)O12 cuboctahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(2) and three equivalent O(3) atoms to form SO4 tetrahedra that share corners with three equivalent Rb(2)O6 octahedra and edges with three equivalent Cs(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 17°. In the second S site, S(2) is bonded to one O(4) and three equivalent O(1) atoms to form SO4 tetrahedra that share corners with three equivalent Rb(2)O6 octahedra and edges with three equivalent Cs(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 17°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Cs(1), two equivalent Cs(2), one Rb(2), and one S(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Cs(2), three equivalent Cs(1), and one S(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cs(1), one Cs(2), one Rb(2), two equivalent Rb(1), and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to three equivalent Cs(1), one Rb(1), and one S(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CsRbSO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.301
_cell_length_b   6.301
_cell_length_c   8.272
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   284.419
_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
  Cs  Cs0  1  0.000  0.000  0.687  1.0
  Cs  Cs1  1  0.667  0.333  0.378  1.0
  Rb  Rb2  1  0.333  0.667  0.996  1.0
  Rb  Rb3  1  0.000  0.000  0.185  1.0
  S  S4  1  0.667  0.333  0.915  1.0
  S  S5  1  0.333  0.667  0.454  1.0
  O  O6  1  0.204  0.408  0.391  1.0
  O  O7  1  0.204  0.796  0.391  1.0
  O  O8  1  0.592  0.796  0.391  1.0
  O  O9  1  0.667  0.333  0.737  1.0
  O  O10  1  0.796  0.592  0.978  1.0
  O  O11  1  0.796  0.204  0.978  1.0
  O  O12  1  0.408  0.204  0.978  1.0
  O  O13  1  0.333  0.667  0.633  1.0
[/CIF]
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