The crystal structure described by RbLi2Be2F7 crystallizes in the monoclinic P2_1/c space group. Rb(1) is bonded in a 8-coordinate geometry to one F(3), one F(5), two equivalent F(2), two equivalent F(4), and two equivalent F(6) atoms. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(2), one F(4), and two equivalent F(7) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(1)F4 tetrahedra and corners with four equivalent Be(2)F4 tetrahedra. In the second Li site, Li(2) is bonded to one F(3), one F(6), and two equivalent F(1) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(2)F4 tetrahedra and corners with four equivalent Be(1)F4 tetrahedra. There are two inequivalent Be sites. In the first Be site, Be(1) is bonded to one F(1), one F(3), one F(5), and one F(6) atom to form BeF4 tetrahedra that share  a cornercorner with one Be(2)F4 tetrahedra and corners with four equivalent Li(2)F4 tetrahedra. In the second Be site, Be(2) is bonded to one F(2), one F(4), one F(5), and one F(7) atom to form BeF4 tetrahedra that share  a cornercorner with one Be(1)F4 tetrahedra and corners with four equivalent Li(1)F4 tetrahedra. There are seven inequivalent F sites. In the first F site, F(7) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Be(2) atom. In the second F site, F(1) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Be(1) atom. In the third F site, F(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one Li(1), and one Be(2) atom. In the fourth F site, F(3) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one Li(2), and one Be(1) atom. In the fifth F site, F(4) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one Li(1), and one Be(2) atom. In the sixth F site, F(5) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one Be(1), and one Be(2) atom. In the seventh F site, F(6) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one Li(2), and one Be(1) atom. is represented by the CIF file [CIF]
data_RbLi2Be2F7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.025
_cell_length_b   10.196
_cell_length_c   12.586
_cell_angle_alpha   89.813
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   644.769
_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  0.233  0.360  0.250  1.0
  Rb  Rb1  1  0.267  0.860  0.250  1.0
  Rb  Rb2  1  0.767  0.640  0.750  1.0
  Rb  Rb3  1  0.733  0.140  0.750  1.0
  Li  Li4  1  0.707  0.348  0.999  1.0
  Li  Li5  1  0.207  0.152  0.001  1.0
  Li  Li6  1  0.210  0.150  0.499  1.0
  Li  Li7  1  0.293  0.652  0.001  1.0
  Li  Li8  1  0.790  0.850  0.501  1.0
  Li  Li9  1  0.710  0.350  0.501  1.0
  Li  Li10  1  0.793  0.848  0.999  1.0
  Li  Li11  1  0.290  0.650  0.499  1.0
  Be  Be12  1  0.725  0.101  0.366  1.0
  Be  Be13  1  0.214  0.403  0.868  1.0
  Be  Be14  1  0.275  0.899  0.634  1.0
  Be  Be15  1  0.786  0.597  0.132  1.0
  Be  Be16  1  0.714  0.097  0.132  1.0
  Be  Be17  1  0.775  0.601  0.366  1.0
  Be  Be18  1  0.225  0.399  0.634  1.0
  Be  Be19  1  0.286  0.903  0.868  1.0
  F  F20  1  0.130  0.804  0.555  1.0
  F  F21  1  0.803  0.953  0.120  1.0
  F  F22  1  0.324  0.541  0.618  1.0
  F  F23  1  0.676  0.459  0.382  1.0
  F  F24  1  0.408  0.110  0.122  1.0
  F  F25  1  0.176  0.041  0.618  1.0
  F  F26  1  0.700  0.650  0.248  1.0
  F  F27  1  0.697  0.453  0.120  1.0
  F  F28  1  0.420  0.110  0.380  1.0
  F  F29  1  0.300  0.350  0.752  1.0
  F  F30  1  0.592  0.890  0.878  1.0
  F  F31  1  0.920  0.390  0.620  1.0
  F  F32  1  0.856  0.187  0.048  1.0
  F  F33  1  0.197  0.047  0.880  1.0
  F  F34  1  0.080  0.610  0.380  1.0
  F  F35  1  0.356  0.313  0.952  1.0
  F  F36  1  0.303  0.547  0.880  1.0
  F  F37  1  0.200  0.850  0.752  1.0
  F  F38  1  0.870  0.196  0.445  1.0
  F  F39  1  0.908  0.390  0.878  1.0
  F  F40  1  0.630  0.696  0.445  1.0
  F  F41  1  0.824  0.959  0.382  1.0
  F  F42  1  0.092  0.610  0.122  1.0
  F  F43  1  0.144  0.813  0.952  1.0
  F  F44  1  0.370  0.304  0.555  1.0
  F  F45  1  0.644  0.687  0.048  1.0
  F  F46  1  0.800  0.150  0.248  1.0
  F  F47  1  0.580  0.890  0.620  1.0
[/CIF]
.
The crystal structure described by RbLi2Be2F7 crystallizes in the monoclinic P2_1/c space group. Rb(1) is bonded in a 8-coordinate geometry to one F(3), one F(5), two equivalent F(2), two equivalent F(4), and two equivalent F(6) atoms. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(2), one F(4), and two equivalent F(7) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(1)F4 tetrahedra and corners with four equivalent Be(2)F4 tetrahedra. In the second Li site, Li(2) is bonded to one F(3), one F(6), and two equivalent F(1) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(2)F4 tetrahedra and corners with four equivalent Be(1)F4 tetrahedra. There are two inequivalent Be sites. In the first Be site, Be(1) is bonded to one F(1), one F(3), one F(5), and one F(6) atom to form BeF4 tetrahedra that share  a cornercorner with one Be(2)F4 tetrahedra and corners with four equivalent Li(2)F4 tetrahedra. In the second Be site, Be(2) is bonded to one F(2), one F(4), one F(5), and one F(7) atom to form BeF4 tetrahedra that share  a cornercorner with one Be(1)F4 tetrahedra and corners with four equivalent Li(1)F4 tetrahedra. There are seven inequivalent F sites. In the first F site, F(7) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Be(2) atom. In the second F site, F(1) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Be(1) atom. In the third F site, F(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one Li(1), and one Be(2) atom. In the fourth F site, F(3) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one Li(2), and one Be(1) atom. In the fifth F site, F(4) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one Li(1), and one Be(2) atom. In the sixth F site, F(5) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one Be(1), and one Be(2) atom. In the seventh F site, F(6) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one Li(2), and one Be(1) atom. is represented by the CIF file [CIF]
data_RbLi2Be2F7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.025
_cell_length_b   10.196
_cell_length_c   12.586
_cell_angle_alpha   89.813
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   644.769
_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  0.233  0.360  0.250  1.0
  Rb  Rb1  1  0.267  0.860  0.250  1.0
  Rb  Rb2  1  0.767  0.640  0.750  1.0
  Rb  Rb3  1  0.733  0.140  0.750  1.0
  Li  Li4  1  0.707  0.348  0.999  1.0
  Li  Li5  1  0.207  0.152  0.001  1.0
  Li  Li6  1  0.210  0.150  0.499  1.0
  Li  Li7  1  0.293  0.652  0.001  1.0
  Li  Li8  1  0.790  0.850  0.501  1.0
  Li  Li9  1  0.710  0.350  0.501  1.0
  Li  Li10  1  0.793  0.848  0.999  1.0
  Li  Li11  1  0.290  0.650  0.499  1.0
  Be  Be12  1  0.725  0.101  0.366  1.0
  Be  Be13  1  0.214  0.403  0.868  1.0
  Be  Be14  1  0.275  0.899  0.634  1.0
  Be  Be15  1  0.786  0.597  0.132  1.0
  Be  Be16  1  0.714  0.097  0.132  1.0
  Be  Be17  1  0.775  0.601  0.366  1.0
  Be  Be18  1  0.225  0.399  0.634  1.0
  Be  Be19  1  0.286  0.903  0.868  1.0
  F  F20  1  0.130  0.804  0.555  1.0
  F  F21  1  0.803  0.953  0.120  1.0
  F  F22  1  0.324  0.541  0.618  1.0
  F  F23  1  0.676  0.459  0.382  1.0
  F  F24  1  0.408  0.110  0.122  1.0
  F  F25  1  0.176  0.041  0.618  1.0
  F  F26  1  0.700  0.650  0.248  1.0
  F  F27  1  0.697  0.453  0.120  1.0
  F  F28  1  0.420  0.110  0.380  1.0
  F  F29  1  0.300  0.350  0.752  1.0
  F  F30  1  0.592  0.890  0.878  1.0
  F  F31  1  0.920  0.390  0.620  1.0
  F  F32  1  0.856  0.187  0.048  1.0
  F  F33  1  0.197  0.047  0.880  1.0
  F  F34  1  0.080  0.610  0.380  1.0
  F  F35  1  0.356  0.313  0.952  1.0
  F  F36  1  0.303  0.547  0.880  1.0
  F  F37  1  0.200  0.850  0.752  1.0
  F  F38  1  0.870  0.196  0.445  1.0
  F  F39  1  0.908  0.390  0.878  1.0
  F  F40  1  0.630  0.696  0.445  1.0
  F  F41  1  0.824  0.959  0.382  1.0
  F  F42  1  0.092  0.610  0.122  1.0
  F  F43  1  0.144  0.813  0.952  1.0
  F  F44  1  0.370  0.304  0.555  1.0
  F  F45  1  0.644  0.687  0.048  1.0
  F  F46  1  0.800  0.150  0.248  1.0
  F  F47  1  0.580  0.890  0.620  1.0
[/CIF]
.