The compound described by CaBi2O4 crystallizes in the orthorhombic Pmmn space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form distorted CaO6 pentagonal pyramids that share edges with four equivalent Bi(2)O6 octahedra. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(3) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), and two equivalent O(3) atoms. In the second Bi site, Bi(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form BiO6 octahedra that share edges with two equivalent Bi(2)O6 octahedra and edges with two equivalent Ca(1)O6 pentagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Bi(1), and two equivalent Bi(2) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Bi(1), and two equivalent Bi(2) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Ca(2), one Bi(1), and one Bi(2) atom. is represented by the CIF file [CIF]
data_Ca(BiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.127
_cell_length_b   6.890
_cell_length_c   12.009
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   506.937
_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
  Ca  Ca0  1  0.861  0.250  0.750  1.0
  Ca  Ca1  1  0.139  0.750  0.250  1.0
  Ca  Ca2  1  0.510  0.250  0.250  1.0
  Ca  Ca3  1  0.490  0.750  0.750  1.0
  Bi  Bi4  1  0.499  0.750  0.463  1.0
  Bi  Bi5  1  0.499  0.750  0.037  1.0
  Bi  Bi6  1  0.501  0.250  0.537  1.0
  Bi  Bi7  1  0.501  0.250  0.963  1.0
  Bi  Bi8  1  1.000  0.500  0.500  1.0
  Bi  Bi9  1  0.000  1.000  0.000  1.0
  Bi  Bi10  1  1.000  1.000  0.500  1.0
  Bi  Bi11  1  0.000  0.500  0.000  1.0
  O  O12  1  0.875  0.750  0.385  1.0
  O  O13  1  0.875  0.750  0.115  1.0
  O  O14  1  0.125  0.250  0.615  1.0
  O  O15  1  0.125  0.250  0.885  1.0
  O  O16  1  0.225  0.750  0.595  1.0
  O  O17  1  0.225  0.750  0.905  1.0
  O  O18  1  0.775  0.250  0.405  1.0
  O  O19  1  0.775  0.250  0.095  1.0
  O  O20  1  0.676  0.489  0.624  1.0
  O  O21  1  0.676  0.011  0.876  1.0
  O  O22  1  0.324  0.989  0.376  1.0
  O  O23  1  0.324  0.511  0.124  1.0
  O  O24  1  0.324  0.511  0.376  1.0
  O  O25  1  0.324  0.989  0.124  1.0
  O  O26  1  0.676  0.011  0.624  1.0
  O  O27  1  0.676  0.489  0.876  1.0
[/CIF]
.
The compound described by CaBi2O4 crystallizes in the orthorhombic Pmmn space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form distorted CaO6 pentagonal pyramids that share edges with four equivalent Bi(2)O6 octahedra. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(3) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), and two equivalent O(3) atoms. In the second Bi site, Bi(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form BiO6 octahedra that share edges with two equivalent Bi(2)O6 octahedra and edges with two equivalent Ca(1)O6 pentagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Bi(1), and two equivalent Bi(2) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Bi(1), and two equivalent Bi(2) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Ca(2), one Bi(1), and one Bi(2) atom. is represented by the CIF file [CIF]
data_Ca(BiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.127
_cell_length_b   6.890
_cell_length_c   12.009
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   506.937
_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
  Ca  Ca0  1  0.861  0.250  0.750  1.0
  Ca  Ca1  1  0.139  0.750  0.250  1.0
  Ca  Ca2  1  0.510  0.250  0.250  1.0
  Ca  Ca3  1  0.490  0.750  0.750  1.0
  Bi  Bi4  1  0.499  0.750  0.463  1.0
  Bi  Bi5  1  0.499  0.750  0.037  1.0
  Bi  Bi6  1  0.501  0.250  0.537  1.0
  Bi  Bi7  1  0.501  0.250  0.963  1.0
  Bi  Bi8  1  1.000  0.500  0.500  1.0
  Bi  Bi9  1  0.000  1.000  0.000  1.0
  Bi  Bi10  1  1.000  1.000  0.500  1.0
  Bi  Bi11  1  0.000  0.500  0.000  1.0
  O  O12  1  0.875  0.750  0.385  1.0
  O  O13  1  0.875  0.750  0.115  1.0
  O  O14  1  0.125  0.250  0.615  1.0
  O  O15  1  0.125  0.250  0.885  1.0
  O  O16  1  0.225  0.750  0.595  1.0
  O  O17  1  0.225  0.750  0.905  1.0
  O  O18  1  0.775  0.250  0.405  1.0
  O  O19  1  0.775  0.250  0.095  1.0
  O  O20  1  0.676  0.489  0.624  1.0
  O  O21  1  0.676  0.011  0.876  1.0
  O  O22  1  0.324  0.989  0.376  1.0
  O  O23  1  0.324  0.511  0.124  1.0
  O  O24  1  0.324  0.511  0.376  1.0
  O  O25  1  0.324  0.989  0.124  1.0
  O  O26  1  0.676  0.011  0.624  1.0
  O  O27  1  0.676  0.489  0.876  1.0
[/CIF]
.