The crystal structure described by Rb2Be2Si2O7 crystallizes in the orthorhombic Pnn2 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Be(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Rb(2), two equivalent Rb(1), one Be(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Rb(2), one Be(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Rb(2), one Be(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Rb(1) and two equivalent Si(1) atoms. is represented by the CIF file [CIF]
data_Rb2Be2Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.200
_cell_length_b   8.439
_cell_length_c   9.014
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   395.554
_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  0.500  0.000  0.441  1.0
  Rb  Rb1  1  0.000  0.000  0.002  1.0
  Rb  Rb2  1  0.000  0.500  0.941  1.0
  Rb  Rb3  1  0.500  0.500  0.502  1.0
  Be  Be4  1  0.505  0.241  0.812  1.0
  Be  Be5  1  0.995  0.741  0.312  1.0
  Be  Be6  1  0.005  0.259  0.312  1.0
  Be  Be7  1  0.495  0.759  0.812  1.0
  Si  Si8  1  0.996  0.804  0.642  1.0
  Si  Si9  1  0.004  0.196  0.642  1.0
  Si  Si10  1  0.504  0.304  0.142  1.0
  Si  Si11  1  0.496  0.696  0.142  1.0
  O  O12  1  0.281  0.747  0.695  1.0
  O  O13  1  0.074  0.265  0.478  1.0
  O  O14  1  0.279  0.747  0.263  1.0
  O  O15  1  0.721  0.253  0.263  1.0
  O  O16  1  0.719  0.253  0.695  1.0
  O  O17  1  0.000  0.000  0.628  1.0
  O  O18  1  0.779  0.753  0.763  1.0
  O  O19  1  0.926  0.735  0.478  1.0
  O  O20  1  0.500  0.500  0.128  1.0
  O  O21  1  0.574  0.235  0.978  1.0
  O  O22  1  0.219  0.247  0.195  1.0
  O  O23  1  0.221  0.247  0.763  1.0
  O  O24  1  0.426  0.765  0.978  1.0
  O  O25  1  0.781  0.753  0.195  1.0
[/CIF]
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The crystal structure described by Rb2Be2Si2O7 crystallizes in the orthorhombic Pnn2 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Be(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Rb(2), two equivalent Rb(1), one Be(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Rb(2), one Be(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Rb(2), one Be(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Rb(1) and two equivalent Si(1) atoms. is represented by the CIF file [CIF]
data_Rb2Be2Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.200
_cell_length_b   8.439
_cell_length_c   9.014
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   395.554
_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  0.500  0.000  0.441  1.0
  Rb  Rb1  1  0.000  0.000  0.002  1.0
  Rb  Rb2  1  0.000  0.500  0.941  1.0
  Rb  Rb3  1  0.500  0.500  0.502  1.0
  Be  Be4  1  0.505  0.241  0.812  1.0
  Be  Be5  1  0.995  0.741  0.312  1.0
  Be  Be6  1  0.005  0.259  0.312  1.0
  Be  Be7  1  0.495  0.759  0.812  1.0
  Si  Si8  1  0.996  0.804  0.642  1.0
  Si  Si9  1  0.004  0.196  0.642  1.0
  Si  Si10  1  0.504  0.304  0.142  1.0
  Si  Si11  1  0.496  0.696  0.142  1.0
  O  O12  1  0.281  0.747  0.695  1.0
  O  O13  1  0.074  0.265  0.478  1.0
  O  O14  1  0.279  0.747  0.263  1.0
  O  O15  1  0.721  0.253  0.263  1.0
  O  O16  1  0.719  0.253  0.695  1.0
  O  O17  1  0.000  0.000  0.628  1.0
  O  O18  1  0.779  0.753  0.763  1.0
  O  O19  1  0.926  0.735  0.478  1.0
  O  O20  1  0.500  0.500  0.128  1.0
  O  O21  1  0.574  0.235  0.978  1.0
  O  O22  1  0.219  0.247  0.195  1.0
  O  O23  1  0.221  0.247  0.763  1.0
  O  O24  1  0.426  0.765  0.978  1.0
  O  O25  1  0.781  0.753  0.195  1.0
[/CIF]
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