The material described by RbCaI3 crystallizes in the orthorhombic Pnma space group. Rb(1) is bonded in a 8-coordinate geometry to one I(2), three equivalent I(1), and four equivalent I(3) atoms. Ca(1) is bonded to one I(3), two equivalent I(1), and three equivalent I(2) atoms to form edge-sharing CaI6 octahedra. There are three inequivalent I sites. In the first I site, I(1) is bonded in a 5-coordinate geometry to three equivalent Rb(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1) and three equivalent Ca(1) atoms. In the third I site, I(3) is bonded to four equivalent Rb(1) and one Ca(1) atom to form a mixture of distorted corner and edge-sharing IRb4Ca square pyramids. is represented by the CIF file [CIF]
data_RbCaI3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.694
_cell_length_b   10.469
_cell_length_c   17.374
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   853.738
_cell_formula_units_Z   4
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  0.750  0.573  0.175  1.0
  Rb  Rb1  1  0.250  0.427  0.825  1.0
  Rb  Rb2  1  0.750  0.073  0.325  1.0
  Rb  Rb3  1  0.250  0.927  0.675  1.0
  Ca  Ca4  1  0.250  0.665  0.443  1.0
  Ca  Ca5  1  0.750  0.335  0.557  1.0
  Ca  Ca6  1  0.250  0.165  0.057  1.0
  Ca  Ca7  1  0.750  0.835  0.943  1.0
  I  I8  1  0.750  0.834  0.508  1.0
  I  I9  1  0.250  0.166  0.492  1.0
  I  I10  1  0.750  0.334  0.992  1.0
  I  I11  1  0.250  0.666  0.008  1.0
  I  I12  1  0.250  0.525  0.605  1.0
  I  I13  1  0.750  0.475  0.395  1.0
  I  I14  1  0.250  0.025  0.895  1.0
  I  I15  1  0.750  0.975  0.105  1.0
  I  I16  1  0.250  0.794  0.285  1.0
  I  I17  1  0.750  0.206  0.715  1.0
  I  I18  1  0.250  0.294  0.215  1.0
  I  I19  1  0.750  0.706  0.785  1.0
[/CIF]
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The material described by RbCaI3 crystallizes in the orthorhombic Pnma space group. Rb(1) is bonded in a 8-coordinate geometry to one I(2), three equivalent I(1), and four equivalent I(3) atoms. Ca(1) is bonded to one I(3), two equivalent I(1), and three equivalent I(2) atoms to form edge-sharing CaI6 octahedra. There are three inequivalent I sites. In the first I site, I(1) is bonded in a 5-coordinate geometry to three equivalent Rb(1) and two equivalent Ca(1) atoms. In the second I site, I(2) is bonded in a distorted rectangular see-saw-like geometry to one Rb(1) and three equivalent Ca(1) atoms. In the third I site, I(3) is bonded to four equivalent Rb(1) and one Ca(1) atom to form a mixture of distorted corner and edge-sharing IRb4Ca square pyramids. is represented by the CIF file [CIF]
data_RbCaI3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.694
_cell_length_b   10.469
_cell_length_c   17.374
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   853.738
_cell_formula_units_Z   4
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  0.750  0.573  0.175  1.0
  Rb  Rb1  1  0.250  0.427  0.825  1.0
  Rb  Rb2  1  0.750  0.073  0.325  1.0
  Rb  Rb3  1  0.250  0.927  0.675  1.0
  Ca  Ca4  1  0.250  0.665  0.443  1.0
  Ca  Ca5  1  0.750  0.335  0.557  1.0
  Ca  Ca6  1  0.250  0.165  0.057  1.0
  Ca  Ca7  1  0.750  0.835  0.943  1.0
  I  I8  1  0.750  0.834  0.508  1.0
  I  I9  1  0.250  0.166  0.492  1.0
  I  I10  1  0.750  0.334  0.992  1.0
  I  I11  1  0.250  0.666  0.008  1.0
  I  I12  1  0.250  0.525  0.605  1.0
  I  I13  1  0.750  0.475  0.395  1.0
  I  I14  1  0.250  0.025  0.895  1.0
  I  I15  1  0.750  0.975  0.105  1.0
  I  I16  1  0.250  0.794  0.285  1.0
  I  I17  1  0.750  0.206  0.715  1.0
  I  I18  1  0.250  0.294  0.215  1.0
  I  I19  1  0.750  0.706  0.785  1.0
[/CIF]
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