The material described by Rb4CO4 crystallizes in the monoclinic Cm space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted RbO5 trigonal bipyramids that share corners with two equivalent Rb(1)O5 trigonal bipyramids,  an edgeedge with one C(1)O4 tetrahedra, and  a faceface with one C(1)O4 tetrahedra. In the second Rb site, Rb(2) is bonded in a 4-coordinate geometry to one O(2), one O(3), and two equivalent O(1) atoms. In the third Rb site, Rb(3) is bonded in a 4-coordinate geometry to one O(2), one O(3), and two equivalent O(1) atoms. C(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form CO4 tetrahedra that share  an edgeedge with one Rb(1)O5 trigonal bipyramid and  a faceface with one Rb(1)O5 trigonal bipyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), two equivalent Rb(3), and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), two equivalent Rb(3), and one C(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Rb(2), two equivalent Rb(1), two equivalent Rb(3), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb4CO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.243
_cell_length_b   6.243
_cell_length_c   5.906
_cell_angle_alpha   81.983
_cell_angle_beta   81.983
_cell_angle_gamma   112.296
_symmetry_Int_Tables_number   1
_cell_volume   206.216
_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  0.635  0.635  0.256  1.0
  Rb  Rb1  1  0.111  0.111  0.445  1.0
  Rb  Rb2  1  0.851  0.334  0.889  1.0
  Rb  Rb3  1  0.334  0.851  0.889  1.0
  C  C4  1  0.445  0.445  0.753  1.0
  O  O5  1  0.514  0.288  0.632  1.0
  O  O6  1  0.326  0.326  0.990  1.0
  O  O7  1  0.654  0.654  0.752  1.0
  O  O8  1  0.288  0.514  0.632  1.0
[/CIF]
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The material described by Rb4CO4 crystallizes in the monoclinic Cm space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted RbO5 trigonal bipyramids that share corners with two equivalent Rb(1)O5 trigonal bipyramids,  an edgeedge with one C(1)O4 tetrahedra, and  a faceface with one C(1)O4 tetrahedra. In the second Rb site, Rb(2) is bonded in a 4-coordinate geometry to one O(2), one O(3), and two equivalent O(1) atoms. In the third Rb site, Rb(3) is bonded in a 4-coordinate geometry to one O(2), one O(3), and two equivalent O(1) atoms. C(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form CO4 tetrahedra that share  an edgeedge with one Rb(1)O5 trigonal bipyramid and  a faceface with one Rb(1)O5 trigonal bipyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), two equivalent Rb(3), and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), two equivalent Rb(3), and one C(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Rb(2), two equivalent Rb(1), two equivalent Rb(3), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb4CO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.243
_cell_length_b   6.243
_cell_length_c   5.906
_cell_angle_alpha   81.983
_cell_angle_beta   81.983
_cell_angle_gamma   112.296
_symmetry_Int_Tables_number   1
_cell_volume   206.216
_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  0.635  0.635  0.256  1.0
  Rb  Rb1  1  0.111  0.111  0.445  1.0
  Rb  Rb2  1  0.851  0.334  0.889  1.0
  Rb  Rb3  1  0.334  0.851  0.889  1.0
  C  C4  1  0.445  0.445  0.753  1.0
  O  O5  1  0.514  0.288  0.632  1.0
  O  O6  1  0.326  0.326  0.990  1.0
  O  O7  1  0.654  0.654  0.752  1.0
  O  O8  1  0.288  0.514  0.632  1.0
[/CIF]
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