The compound described by Rb2CoI4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 10-coordinate geometry to one Co(1), one I(2), four equivalent I(1), and four equivalent I(3) atoms. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to one I(1), three equivalent I(2), and four equivalent I(3) atoms. Co(1) is bonded to one Rb(1), one I(1), one I(2), and two equivalent I(3) atoms to form CoRbI4 tetrahedra that share corners with four equivalent I(3)Rb4Co square pyramids. There are three inequivalent I sites. In the first I site, I(1) is bonded in a 6-coordinate geometry to one Rb(2), four equivalent Rb(1), and one Co(1) atom. In the second I site, I(2) is bonded in a 5-coordinate geometry to one Rb(1), three equivalent Rb(2), and one Co(1) atom. In the third I site, I(3) is bonded to two equivalent Rb(1), two equivalent Rb(2), and one Co(1) atom to form distorted IRb4Co square pyramids that share corners with four equivalent I(3)Rb4Co square pyramids, corners with two equivalent Co(1)RbI4 tetrahedra, edges with three equivalent I(3)Rb4Co square pyramids, and  a faceface with one I(3)Rb4Co square pyramid. is represented by the CIF file [CIF]
data_Rb2CoI4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.713
_cell_length_b   8.157
_cell_length_c   10.434
_cell_angle_alpha   90.000
_cell_angle_beta   109.448
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   619.017
_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  0.302  0.750  0.963  1.0
  Rb  Rb1  1  0.698  0.250  0.037  1.0
  Rb  Rb2  1  0.798  0.250  0.586  1.0
  Rb  Rb3  1  0.203  0.750  0.414  1.0
  Co  Co4  1  0.303  0.250  0.215  1.0
  Co  Co5  1  0.697  0.750  0.785  1.0
  I  I6  1  0.862  0.750  0.047  1.0
  I  I7  1  0.138  0.250  0.953  1.0
  I  I8  1  0.916  0.750  0.644  1.0
  I  I9  1  0.083  0.250  0.356  1.0
  I  I10  1  0.482  0.002  0.722  1.0
  I  I11  1  0.518  0.502  0.278  1.0
  I  I12  1  0.518  0.998  0.278  1.0
  I  I13  1  0.482  0.498  0.722  1.0
[/CIF]
.
The compound described by Rb2CoI4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 10-coordinate geometry to one Co(1), one I(2), four equivalent I(1), and four equivalent I(3) atoms. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to one I(1), three equivalent I(2), and four equivalent I(3) atoms. Co(1) is bonded to one Rb(1), one I(1), one I(2), and two equivalent I(3) atoms to form CoRbI4 tetrahedra that share corners with four equivalent I(3)Rb4Co square pyramids. There are three inequivalent I sites. In the first I site, I(1) is bonded in a 6-coordinate geometry to one Rb(2), four equivalent Rb(1), and one Co(1) atom. In the second I site, I(2) is bonded in a 5-coordinate geometry to one Rb(1), three equivalent Rb(2), and one Co(1) atom. In the third I site, I(3) is bonded to two equivalent Rb(1), two equivalent Rb(2), and one Co(1) atom to form distorted IRb4Co square pyramids that share corners with four equivalent I(3)Rb4Co square pyramids, corners with two equivalent Co(1)RbI4 tetrahedra, edges with three equivalent I(3)Rb4Co square pyramids, and  a faceface with one I(3)Rb4Co square pyramid. is represented by the CIF file [CIF]
data_Rb2CoI4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.713
_cell_length_b   8.157
_cell_length_c   10.434
_cell_angle_alpha   90.000
_cell_angle_beta   109.448
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   619.017
_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  0.302  0.750  0.963  1.0
  Rb  Rb1  1  0.698  0.250  0.037  1.0
  Rb  Rb2  1  0.798  0.250  0.586  1.0
  Rb  Rb3  1  0.203  0.750  0.414  1.0
  Co  Co4  1  0.303  0.250  0.215  1.0
  Co  Co5  1  0.697  0.750  0.785  1.0
  I  I6  1  0.862  0.750  0.047  1.0
  I  I7  1  0.138  0.250  0.953  1.0
  I  I8  1  0.916  0.750  0.644  1.0
  I  I9  1  0.083  0.250  0.356  1.0
  I  I10  1  0.482  0.002  0.722  1.0
  I  I11  1  0.518  0.502  0.278  1.0
  I  I12  1  0.518  0.998  0.278  1.0
  I  I13  1  0.482  0.498  0.722  1.0
[/CIF]
.