The material structure described by Rb3AlO3 crystallizes in the monoclinic C2/m space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. In the third Rb site, Rb(3) is bonded to four equivalent O(1) atoms to form distorted RbO4 tetrahedra that share corners with four equivalent Al(1)O4 tetrahedra and edges with two equivalent Rb(3)O4 tetrahedra. Al(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Rb(3)O4 tetrahedra and  an edgeedge with one Al(1)O4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), two equivalent Rb(3), and one Al(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Rb(1), two equivalent Rb(2), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb3AlO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.765
_cell_length_b   6.765
_cell_length_c   6.790
_cell_angle_alpha   97.631
_cell_angle_beta   97.631
_cell_angle_gamma   115.098
_symmetry_Int_Tables_number   1
_cell_volume   272.673
_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  0.370  0.370  0.653  1.0
  Rb  Rb1  1  0.630  0.630  0.347  1.0
  Rb  Rb2  1  0.198  0.802  0.500  1.0
  Rb  Rb3  1  0.802  0.198  0.500  1.0
  Rb  Rb4  1  0.268  0.732  0.000  1.0
  Rb  Rb5  1  0.732  0.268  0.000  1.0
  Al  Al6  1  0.844  0.844  0.854  1.0
  Al  Al7  1  0.156  0.156  0.146  1.0
  O  O8  1  0.853  0.600  0.738  1.0
  O  O9  1  0.400  0.147  0.262  1.0
  O  O10  1  0.147  0.400  0.262  1.0
  O  O11  1  0.600  0.853  0.738  1.0
  O  O12  1  0.901  0.901  0.132  1.0
  O  O13  1  0.099  0.099  0.868  1.0
[/CIF]
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The material structure described by Rb3AlO3 crystallizes in the monoclinic C2/m space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. In the third Rb site, Rb(3) is bonded to four equivalent O(1) atoms to form distorted RbO4 tetrahedra that share corners with four equivalent Al(1)O4 tetrahedra and edges with two equivalent Rb(3)O4 tetrahedra. Al(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Rb(3)O4 tetrahedra and  an edgeedge with one Al(1)O4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), two equivalent Rb(3), and one Al(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Rb(1), two equivalent Rb(2), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb3AlO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.765
_cell_length_b   6.765
_cell_length_c   6.790
_cell_angle_alpha   97.631
_cell_angle_beta   97.631
_cell_angle_gamma   115.098
_symmetry_Int_Tables_number   1
_cell_volume   272.673
_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  0.370  0.370  0.653  1.0
  Rb  Rb1  1  0.630  0.630  0.347  1.0
  Rb  Rb2  1  0.198  0.802  0.500  1.0
  Rb  Rb3  1  0.802  0.198  0.500  1.0
  Rb  Rb4  1  0.268  0.732  0.000  1.0
  Rb  Rb5  1  0.732  0.268  0.000  1.0
  Al  Al6  1  0.844  0.844  0.854  1.0
  Al  Al7  1  0.156  0.156  0.146  1.0
  O  O8  1  0.853  0.600  0.738  1.0
  O  O9  1  0.400  0.147  0.262  1.0
  O  O10  1  0.147  0.400  0.262  1.0
  O  O11  1  0.600  0.853  0.738  1.0
  O  O12  1  0.901  0.901  0.132  1.0
  O  O13  1  0.099  0.099  0.868  1.0
[/CIF]
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