The material structure described by Rb2Al2B2O7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 8-coordinate geometry to one O(1), one O(7), two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to one O(1), one O(6), one O(7), and two equivalent O(4) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form corner-sharing AlO4 tetrahedra. There are two inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(1), one O(5), and one O(7) atom. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(2), one O(3), and one O(6) atom. There are seven inequivalent O sites. In the first O site, O(7) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Al(1), and one B(1) atom. In the second O site, O(1) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Al(2), and one B(1) atom. In the third O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one Al(2), and one B(2) atom. In the fourth O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Rb(1), one Al(1), and one B(2) atom. In the fifth O site, O(4) is bonded in a distorted bent 150 degrees geometry to two equivalent Rb(2), one Al(1), and one Al(2) atom. In the sixth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Rb(1), one Al(2), and one B(1) atom. In the seventh O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Rb(2), one Al(1), and one B(2) atom. is represented by the CIF file [CIF]
data_Rb2Al2B2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.667
_cell_length_b   9.010
_cell_length_c   12.076
_cell_angle_alpha   75.935
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   809.219
_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  0.360  0.965  0.128  1.0
  Rb  Rb1  1  0.860  0.035  0.372  1.0
  Rb  Rb2  1  0.867  0.543  0.853  1.0
  Rb  Rb3  1  0.367  0.457  0.647  1.0
  Rb  Rb4  1  0.633  0.543  0.353  1.0
  Rb  Rb5  1  0.640  0.035  0.872  1.0
  Rb  Rb6  1  0.140  0.965  0.628  1.0
  Rb  Rb7  1  0.133  0.457  0.147  1.0
  Al  Al8  1  0.877  0.342  0.622  1.0
  Al  Al9  1  0.623  0.342  0.122  1.0
  Al  Al10  1  0.377  0.658  0.878  1.0
  Al  Al11  1  0.583  0.815  0.634  1.0
  Al  Al12  1  0.417  0.185  0.366  1.0
  Al  Al13  1  0.083  0.185  0.866  1.0
  Al  Al14  1  0.917  0.815  0.134  1.0
  Al  Al15  1  0.123  0.658  0.378  1.0
  B  B16  1  0.411  0.844  0.412  1.0
  B  B17  1  0.116  0.319  0.438  1.0
  B  B18  1  0.589  0.156  0.588  1.0
  B  B19  1  0.616  0.681  0.062  1.0
  B  B20  1  0.089  0.844  0.912  1.0
  B  B21  1  0.384  0.319  0.938  1.0
  B  B22  1  0.884  0.681  0.562  1.0
  B  B23  1  0.911  0.156  0.088  1.0
  O  O24  1  0.539  0.229  0.479  1.0
  O  O25  1  0.808  0.797  0.604  1.0
  O  O26  1  0.969  0.282  0.505  1.0
  O  O27  1  0.019  0.308  0.738  1.0
  O  O28  1  0.469  0.718  0.995  1.0
  O  O29  1  0.542  0.006  0.639  1.0
  O  O30  1  0.812  0.537  0.589  1.0
  O  O31  1  0.458  0.994  0.361  1.0
  O  O32  1  0.308  0.203  0.896  1.0
  O  O33  1  0.039  0.771  0.021  1.0
  O  O34  1  0.461  0.771  0.521  1.0
  O  O35  1  0.312  0.463  0.911  1.0
  O  O36  1  0.688  0.537  0.089  1.0
  O  O37  1  0.180  0.763  0.847  1.0
  O  O38  1  0.320  0.763  0.347  1.0
  O  O39  1  0.519  0.692  0.762  1.0
  O  O40  1  0.958  0.006  0.139  1.0
  O  O41  1  0.188  0.463  0.411  1.0
  O  O42  1  0.192  0.203  0.396  1.0
  O  O43  1  0.680  0.237  0.653  1.0
  O  O44  1  0.042  0.994  0.861  1.0
  O  O45  1  0.031  0.718  0.495  1.0
  O  O46  1  0.961  0.229  0.979  1.0
  O  O47  1  0.692  0.797  0.104  1.0
  O  O48  1  0.820  0.237  0.153  1.0
  O  O49  1  0.531  0.282  0.005  1.0
  O  O50  1  0.481  0.308  0.238  1.0
  O  O51  1  0.981  0.692  0.262  1.0
[/CIF]
.
The material structure described by Rb2Al2B2O7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 8-coordinate geometry to one O(1), one O(7), two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to one O(1), one O(6), one O(7), and two equivalent O(4) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form corner-sharing AlO4 tetrahedra. There are two inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(1), one O(5), and one O(7) atom. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(2), one O(3), and one O(6) atom. There are seven inequivalent O sites. In the first O site, O(7) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Al(1), and one B(1) atom. In the second O site, O(1) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Al(2), and one B(1) atom. In the third O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one Al(2), and one B(2) atom. In the fourth O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Rb(1), one Al(1), and one B(2) atom. In the fifth O site, O(4) is bonded in a distorted bent 150 degrees geometry to two equivalent Rb(2), one Al(1), and one Al(2) atom. In the sixth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Rb(1), one Al(2), and one B(1) atom. In the seventh O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Rb(2), one Al(1), and one B(2) atom. is represented by the CIF file [CIF]
data_Rb2Al2B2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.667
_cell_length_b   9.010
_cell_length_c   12.076
_cell_angle_alpha   75.935
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   809.219
_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  0.360  0.965  0.128  1.0
  Rb  Rb1  1  0.860  0.035  0.372  1.0
  Rb  Rb2  1  0.867  0.543  0.853  1.0
  Rb  Rb3  1  0.367  0.457  0.647  1.0
  Rb  Rb4  1  0.633  0.543  0.353  1.0
  Rb  Rb5  1  0.640  0.035  0.872  1.0
  Rb  Rb6  1  0.140  0.965  0.628  1.0
  Rb  Rb7  1  0.133  0.457  0.147  1.0
  Al  Al8  1  0.877  0.342  0.622  1.0
  Al  Al9  1  0.623  0.342  0.122  1.0
  Al  Al10  1  0.377  0.658  0.878  1.0
  Al  Al11  1  0.583  0.815  0.634  1.0
  Al  Al12  1  0.417  0.185  0.366  1.0
  Al  Al13  1  0.083  0.185  0.866  1.0
  Al  Al14  1  0.917  0.815  0.134  1.0
  Al  Al15  1  0.123  0.658  0.378  1.0
  B  B16  1  0.411  0.844  0.412  1.0
  B  B17  1  0.116  0.319  0.438  1.0
  B  B18  1  0.589  0.156  0.588  1.0
  B  B19  1  0.616  0.681  0.062  1.0
  B  B20  1  0.089  0.844  0.912  1.0
  B  B21  1  0.384  0.319  0.938  1.0
  B  B22  1  0.884  0.681  0.562  1.0
  B  B23  1  0.911  0.156  0.088  1.0
  O  O24  1  0.539  0.229  0.479  1.0
  O  O25  1  0.808  0.797  0.604  1.0
  O  O26  1  0.969  0.282  0.505  1.0
  O  O27  1  0.019  0.308  0.738  1.0
  O  O28  1  0.469  0.718  0.995  1.0
  O  O29  1  0.542  0.006  0.639  1.0
  O  O30  1  0.812  0.537  0.589  1.0
  O  O31  1  0.458  0.994  0.361  1.0
  O  O32  1  0.308  0.203  0.896  1.0
  O  O33  1  0.039  0.771  0.021  1.0
  O  O34  1  0.461  0.771  0.521  1.0
  O  O35  1  0.312  0.463  0.911  1.0
  O  O36  1  0.688  0.537  0.089  1.0
  O  O37  1  0.180  0.763  0.847  1.0
  O  O38  1  0.320  0.763  0.347  1.0
  O  O39  1  0.519  0.692  0.762  1.0
  O  O40  1  0.958  0.006  0.139  1.0
  O  O41  1  0.188  0.463  0.411  1.0
  O  O42  1  0.192  0.203  0.396  1.0
  O  O43  1  0.680  0.237  0.653  1.0
  O  O44  1  0.042  0.994  0.861  1.0
  O  O45  1  0.031  0.718  0.495  1.0
  O  O46  1  0.961  0.229  0.979  1.0
  O  O47  1  0.692  0.797  0.104  1.0
  O  O48  1  0.820  0.237  0.153  1.0
  O  O49  1  0.531  0.282  0.005  1.0
  O  O50  1  0.481  0.308  0.238  1.0
  O  O51  1  0.981  0.692  0.262  1.0
[/CIF]
.