The crystal structure described by Rb5Nb3OF18 crystallizes in the tetragonal I4cm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to two equivalent F(1), two equivalent F(3), and eight equivalent F(2) atoms to form RbF12 cuboctahedra that share faces with two equivalent Rb(1)F12 cuboctahedra and faces with four equivalent Nb(1)F7 pentagonal bipyramids. In the second Rb site, Rb(2) is bonded in a 10-coordinate geometry to one F(1), one F(2), one F(3), one F(6), three equivalent F(4), and three equivalent F(5) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one F(1), one F(3), one F(6), two equivalent F(2), and two equivalent F(5) atoms to form distorted NbF7 pentagonal bipyramids that share faces with two equivalent Rb(1)F12 cuboctahedra. In the second Nb site, Nb(2) is bonded to two equivalent O(1) and four equivalent F(4) atoms to form corner-sharing NbO2F4 octahedra. The corner-sharing octahedra are not tilted. O(1) is bonded in a linear geometry to two equivalent Nb(2) atoms. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Nb(1) atom. In the second F site, F(6) is bonded in a distorted trigonal planar geometry to two equivalent Rb(2) and one Nb(1) atom. In the third F site, F(2) is bonded in a 4-coordinate geometry to one Rb(2), two equivalent Rb(1), and one Nb(1) atom. In the fourth F site, F(3) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Nb(1) atom. In the fifth F site, F(4) is bonded in a distorted single-bond geometry to three equivalent Rb(2) and one Nb(2) atom. In the sixth F site, F(5) is bonded in a distorted single-bond geometry to three equivalent Rb(2) and one Nb(1) atom. is represented by the CIF file [CIF]
data_Rb5Nb3OF18
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.877
_cell_length_b   11.877
_cell_length_c   11.877
_cell_angle_alpha   96.469
_cell_angle_beta   96.469
_cell_angle_gamma   140.774
_symmetry_Int_Tables_number   1
_cell_volume   998.131
_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  0.237  0.737  0.500  1.0
  Rb  Rb1  1  0.737  0.237  0.500  1.0
  Rb  Rb2  1  0.188  0.882  0.140  1.0
  Rb  Rb3  1  0.049  0.188  0.307  1.0
  Rb  Rb4  1  0.882  0.742  0.693  1.0
  Rb  Rb5  1  0.742  0.049  0.860  1.0
  Rb  Rb6  1  0.382  0.688  0.140  1.0
  Rb  Rb7  1  0.549  0.242  0.860  1.0
  Rb  Rb8  1  0.688  0.549  0.307  1.0
  Rb  Rb9  1  0.242  0.382  0.693  1.0
  Nb  Nb10  1  0.344  0.156  0.500  1.0
  Nb  Nb11  1  0.844  0.344  0.188  1.0
  Nb  Nb12  1  0.156  0.656  0.812  1.0
  Nb  Nb13  1  0.656  0.844  0.500  1.0
  Nb  Nb14  1  0.734  0.734  0.000  1.0
  Nb  Nb15  1  0.234  0.234  0.000  1.0
  O  O16  1  0.007  0.007  0.000  1.0
  O  O17  1  0.507  0.507  0.000  1.0
  F  F18  1  0.608  0.379  0.500  1.0
  F  F19  1  0.108  0.608  0.229  1.0
  F  F20  1  0.379  0.879  0.771  1.0
  F  F21  1  0.879  0.108  0.500  1.0
  F  F22  1  0.011  0.622  0.670  1.0
  F  F23  1  0.342  0.011  0.390  1.0
  F  F24  1  0.622  0.952  0.610  1.0
  F  F25  1  0.952  0.342  0.330  1.0
  F  F26  1  0.122  0.511  0.670  1.0
  F  F27  1  0.842  0.452  0.330  1.0
  F  F28  1  0.511  0.842  0.390  1.0
  F  F29  1  0.452  0.122  0.610  1.0
  F  F30  1  0.400  0.608  0.500  1.0
  F  F31  1  0.900  0.400  0.791  1.0
  F  F32  1  0.608  0.108  0.209  1.0
  F  F33  1  0.108  0.900  0.500  1.0
  F  F34  1  0.649  0.719  0.840  1.0
  F  F35  1  0.809  0.649  0.930  1.0
  F  F36  1  0.719  0.879  0.070  1.0
  F  F37  1  0.879  0.809  0.160  1.0
  F  F38  1  0.219  0.149  0.840  1.0
  F  F39  1  0.309  0.379  0.160  1.0
  F  F40  1  0.149  0.309  0.930  1.0
  F  F41  1  0.379  0.219  0.070  1.0
  F  F42  1  0.801  0.460  0.123  1.0
  F  F43  1  0.678  0.801  0.341  1.0
  F  F44  1  0.460  0.337  0.659  1.0
  F  F45  1  0.337  0.678  0.877  1.0
  F  F46  1  0.960  0.301  0.123  1.0
  F  F47  1  0.178  0.837  0.877  1.0
  F  F48  1  0.301  0.178  0.341  1.0
  F  F49  1  0.837  0.960  0.659  1.0
  F  F50  1  0.660  0.679  0.500  1.0
  F  F51  1  0.160  0.660  0.981  1.0
  F  F52  1  0.679  0.179  0.019  1.0
  F  F53  1  0.179  0.160  0.500  1.0
[/CIF]
.
The crystal structure described by Rb5Nb3OF18 crystallizes in the tetragonal I4cm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to two equivalent F(1), two equivalent F(3), and eight equivalent F(2) atoms to form RbF12 cuboctahedra that share faces with two equivalent Rb(1)F12 cuboctahedra and faces with four equivalent Nb(1)F7 pentagonal bipyramids. In the second Rb site, Rb(2) is bonded in a 10-coordinate geometry to one F(1), one F(2), one F(3), one F(6), three equivalent F(4), and three equivalent F(5) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one F(1), one F(3), one F(6), two equivalent F(2), and two equivalent F(5) atoms to form distorted NbF7 pentagonal bipyramids that share faces with two equivalent Rb(1)F12 cuboctahedra. In the second Nb site, Nb(2) is bonded to two equivalent O(1) and four equivalent F(4) atoms to form corner-sharing NbO2F4 octahedra. The corner-sharing octahedra are not tilted. O(1) is bonded in a linear geometry to two equivalent Nb(2) atoms. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Nb(1) atom. In the second F site, F(6) is bonded in a distorted trigonal planar geometry to two equivalent Rb(2) and one Nb(1) atom. In the third F site, F(2) is bonded in a 4-coordinate geometry to one Rb(2), two equivalent Rb(1), and one Nb(1) atom. In the fourth F site, F(3) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Nb(1) atom. In the fifth F site, F(4) is bonded in a distorted single-bond geometry to three equivalent Rb(2) and one Nb(2) atom. In the sixth F site, F(5) is bonded in a distorted single-bond geometry to three equivalent Rb(2) and one Nb(1) atom. is represented by the CIF file [CIF]
data_Rb5Nb3OF18
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.877
_cell_length_b   11.877
_cell_length_c   11.877
_cell_angle_alpha   96.469
_cell_angle_beta   96.469
_cell_angle_gamma   140.774
_symmetry_Int_Tables_number   1
_cell_volume   998.131
_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  0.237  0.737  0.500  1.0
  Rb  Rb1  1  0.737  0.237  0.500  1.0
  Rb  Rb2  1  0.188  0.882  0.140  1.0
  Rb  Rb3  1  0.049  0.188  0.307  1.0
  Rb  Rb4  1  0.882  0.742  0.693  1.0
  Rb  Rb5  1  0.742  0.049  0.860  1.0
  Rb  Rb6  1  0.382  0.688  0.140  1.0
  Rb  Rb7  1  0.549  0.242  0.860  1.0
  Rb  Rb8  1  0.688  0.549  0.307  1.0
  Rb  Rb9  1  0.242  0.382  0.693  1.0
  Nb  Nb10  1  0.344  0.156  0.500  1.0
  Nb  Nb11  1  0.844  0.344  0.188  1.0
  Nb  Nb12  1  0.156  0.656  0.812  1.0
  Nb  Nb13  1  0.656  0.844  0.500  1.0
  Nb  Nb14  1  0.734  0.734  0.000  1.0
  Nb  Nb15  1  0.234  0.234  0.000  1.0
  O  O16  1  0.007  0.007  0.000  1.0
  O  O17  1  0.507  0.507  0.000  1.0
  F  F18  1  0.608  0.379  0.500  1.0
  F  F19  1  0.108  0.608  0.229  1.0
  F  F20  1  0.379  0.879  0.771  1.0
  F  F21  1  0.879  0.108  0.500  1.0
  F  F22  1  0.011  0.622  0.670  1.0
  F  F23  1  0.342  0.011  0.390  1.0
  F  F24  1  0.622  0.952  0.610  1.0
  F  F25  1  0.952  0.342  0.330  1.0
  F  F26  1  0.122  0.511  0.670  1.0
  F  F27  1  0.842  0.452  0.330  1.0
  F  F28  1  0.511  0.842  0.390  1.0
  F  F29  1  0.452  0.122  0.610  1.0
  F  F30  1  0.400  0.608  0.500  1.0
  F  F31  1  0.900  0.400  0.791  1.0
  F  F32  1  0.608  0.108  0.209  1.0
  F  F33  1  0.108  0.900  0.500  1.0
  F  F34  1  0.649  0.719  0.840  1.0
  F  F35  1  0.809  0.649  0.930  1.0
  F  F36  1  0.719  0.879  0.070  1.0
  F  F37  1  0.879  0.809  0.160  1.0
  F  F38  1  0.219  0.149  0.840  1.0
  F  F39  1  0.309  0.379  0.160  1.0
  F  F40  1  0.149  0.309  0.930  1.0
  F  F41  1  0.379  0.219  0.070  1.0
  F  F42  1  0.801  0.460  0.123  1.0
  F  F43  1  0.678  0.801  0.341  1.0
  F  F44  1  0.460  0.337  0.659  1.0
  F  F45  1  0.337  0.678  0.877  1.0
  F  F46  1  0.960  0.301  0.123  1.0
  F  F47  1  0.178  0.837  0.877  1.0
  F  F48  1  0.301  0.178  0.341  1.0
  F  F49  1  0.837  0.960  0.659  1.0
  F  F50  1  0.660  0.679  0.500  1.0
  F  F51  1  0.160  0.660  0.981  1.0
  F  F52  1  0.679  0.179  0.019  1.0
  F  F53  1  0.179  0.160  0.500  1.0
[/CIF]
.