The structure described by KTb2F7 crystallizes in the monoclinic C2/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 10-coordinate geometry to one F(3), one F(4), one F(5), one F(8), two equivalent F(9), and four equivalent F(2) atoms. In the second K site, K(2) is bonded in a 5-coordinate geometry to one F(10), one F(4), one F(5), and two equivalent F(1) atoms. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a body-centered cubic geometry to two equivalent F(1), two equivalent F(2), two equivalent F(5), and two equivalent F(8) atoms. In the second Tb site, Tb(2) is bonded in a 8-coordinate geometry to one F(10), one F(8), two equivalent F(1), two equivalent F(6), and two equivalent F(9) atoms. In the third Tb site, Tb(3) is bonded in a 8-coordinate geometry to one F(1), one F(10), one F(2), one F(3), one F(4), one F(6), one F(7), and one F(9) atom. There are ten inequivalent F sites. In the first F site, F(7) is bonded in a distorted bent 150 degrees geometry to two equivalent Tb(3) atoms. In the second F site, F(8) is bonded to one K(1), one Tb(2), and two equivalent Tb(1) atoms to form distorted FKTb3 tetrahedra that share  a cornercorner with one F(4)K2Tb2 tetrahedra,  a cornercorner with one F(10)KTb3 tetrahedra, corners with two equivalent F(1)KTb3 tetrahedra, corners with four equivalent F(2)K2Tb2 tetrahedra, corners with five equivalent F(5)K2Tb2 tetrahedra,  an edgeedge with one F(8)KTb3 tetrahedra, edges with two equivalent F(2)K2Tb2 tetrahedra, and edges with two equivalent F(1)KTb3 tetrahedra. In the third F site, F(9) is bonded in a 2-coordinate geometry to one K(1), one Tb(2), and one Tb(3) atom. In the fourth F site, F(10) is bonded to one K(2), one Tb(2), and two equivalent Tb(3) atoms to form FKTb3 tetrahedra that share  a cornercorner with one F(4)K2Tb2 tetrahedra,  a cornercorner with one F(5)K2Tb2 tetrahedra,  a cornercorner with one F(8)KTb3 tetrahedra, corners with two equivalent F(2)K2Tb2 tetrahedra, corners with two equivalent F(1)KTb3 tetrahedra,  an edgeedge with one F(4)K2Tb2 tetrahedra, and edges with two equivalent F(1)KTb3 tetrahedra. In the fifth F site, F(1) is bonded to one K(2), one Tb(1), one Tb(2), and one Tb(3) atom to form FKTb3 tetrahedra that share  a cornercorner with one F(2)K2Tb2 tetrahedra,  a cornercorner with one F(5)K2Tb2 tetrahedra,  a cornercorner with one F(10)KTb3 tetrahedra,  a cornercorner with one F(8)KTb3 tetrahedra, corners with two equivalent F(4)K2Tb2 tetrahedra, corners with three equivalent F(1)KTb3 tetrahedra,  an edgeedge with one F(2)K2Tb2 tetrahedra,  an edgeedge with one F(5)K2Tb2 tetrahedra,  an edgeedge with one F(10)KTb3 tetrahedra, and  an edgeedge with one F(8)KTb3 tetrahedra. In the sixth F site, F(2) is bonded to two equivalent K(1), one Tb(1), and one Tb(3) atom to form FK2Tb2 tetrahedra that share  a cornercorner with one F(4)K2Tb2 tetrahedra,  a cornercorner with one F(1)KTb3 tetrahedra,  a cornercorner with one F(10)KTb3 tetrahedra, corners with two equivalent F(5)K2Tb2 tetrahedra, corners with two equivalent F(8)KTb3 tetrahedra, corners with five equivalent F(2)K2Tb2 tetrahedra,  an edgeedge with one F(2)K2Tb2 tetrahedra,  an edgeedge with one F(4)K2Tb2 tetrahedra,  an edgeedge with one F(5)K2Tb2 tetrahedra,  an edgeedge with one F(1)KTb3 tetrahedra, and  an edgeedge with one F(8)KTb3 tetrahedra. In the seventh F site, F(3) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Tb(3) atoms. In the eighth F site, F(4) is bonded to one K(1), one K(2), and two equivalent Tb(3) atoms to form FK2Tb2 tetrahedra that share  a cornercorner with one F(10)KTb3 tetrahedra,  a cornercorner with one F(8)KTb3 tetrahedra, corners with two equivalent F(2)K2Tb2 tetrahedra, corners with four equivalent F(1)KTb3 tetrahedra,  an edgeedge with one F(5)K2Tb2 tetrahedra,  an edgeedge with one F(10)KTb3 tetrahedra, and edges with two equivalent F(2)K2Tb2 tetrahedra. In the ninth F site, F(5) is bonded to one K(1), one K(2), and two equivalent Tb(1) atoms to form FK2Tb2 tetrahedra that share  a cornercorner with one F(10)KTb3 tetrahedra, corners with two equivalent F(1)KTb3 tetrahedra, corners with four equivalent F(2)K2Tb2 tetrahedra, corners with five equivalent F(8)KTb3 tetrahedra,  an edgeedge with one F(4)K2Tb2 tetrahedra,  an edgeedge with one F(5)K2Tb2 tetrahedra, edges with two equivalent F(2)K2Tb2 tetrahedra, and edges with two equivalent F(1)KTb3 tetrahedra. In the tenth F site, F(6) is bonded in a distorted bent 150 degrees geometry to one Tb(2) and one Tb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KTb2F7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.213
_cell_length_b   8.213
_cell_length_c   11.993
_cell_angle_alpha   59.614
_cell_angle_beta   59.614
_cell_angle_gamma   58.548
_symmetry_Int_Tables_number   1
_cell_volume   562.152
_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
  K  K0  1  0.763  0.763  0.479  1.0
  K  K1  1  0.267  0.267  0.152  1.0
  K  K2  1  0.733  0.733  0.848  1.0
  K  K3  1  0.237  0.237  0.521  1.0
  Tb  Tb4  1  0.240  0.760  0.500  1.0
  Tb  Tb5  1  0.760  0.240  0.500  1.0
  Tb  Tb6  1  0.740  0.740  0.179  1.0
  Tb  Tb7  1  0.260  0.260  0.821  1.0
  Tb  Tb8  1  0.266  0.740  0.817  1.0
  Tb  Tb9  1  0.740  0.266  0.817  1.0
  Tb  Tb10  1  0.260  0.734  0.183  1.0
  Tb  Tb11  1  0.734  0.260  0.183  1.0
  F  F12  1  0.381  0.854  0.263  1.0
  F  F13  1  0.854  0.381  0.263  1.0
  F  F14  1  0.370  0.838  0.582  1.0
  F  F15  1  0.838  0.370  0.582  1.0
  F  F16  1  0.995  0.995  0.238  1.0
  F  F17  1  0.606  0.606  0.748  1.0
  F  F18  1  0.894  0.894  0.575  1.0
  F  F19  1  0.005  0.669  0.000  1.0
  F  F20  1  0.669  0.005  0.000  1.0
  F  F21  1  0.394  0.394  0.252  1.0
  F  F22  1  0.995  0.331  1.000  1.0
  F  F23  1  0.331  0.995  1.000  1.0
  F  F24  1  0.146  0.619  0.737  1.0
  F  F25  1  0.619  0.146  0.737  1.0
  F  F26  1  0.324  0.676  0.000  1.0
  F  F27  1  0.676  0.324  0.000  1.0
  F  F28  1  0.005  0.005  0.762  1.0
  F  F29  1  0.605  0.605  0.413  1.0
  F  F30  1  0.997  0.655  0.241  1.0
  F  F31  1  0.655  0.997  0.241  1.0
  F  F32  1  0.003  0.345  0.759  1.0
  F  F33  1  0.345  0.003  0.759  1.0
  F  F34  1  0.387  0.387  0.882  1.0
  F  F35  1  0.106  0.106  0.425  1.0
  F  F36  1  0.395  0.395  0.587  1.0
  F  F37  1  0.162  0.630  0.418  1.0
  F  F38  1  0.630  0.162  0.418  1.0
  F  F39  1  0.613  0.613  0.118  1.0
[/CIF]
.
The structure described by KTb2F7 crystallizes in the monoclinic C2/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 10-coordinate geometry to one F(3), one F(4), one F(5), one F(8), two equivalent F(9), and four equivalent F(2) atoms. In the second K site, K(2) is bonded in a 5-coordinate geometry to one F(10), one F(4), one F(5), and two equivalent F(1) atoms. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a body-centered cubic geometry to two equivalent F(1), two equivalent F(2), two equivalent F(5), and two equivalent F(8) atoms. In the second Tb site, Tb(2) is bonded in a 8-coordinate geometry to one F(10), one F(8), two equivalent F(1), two equivalent F(6), and two equivalent F(9) atoms. In the third Tb site, Tb(3) is bonded in a 8-coordinate geometry to one F(1), one F(10), one F(2), one F(3), one F(4), one F(6), one F(7), and one F(9) atom. There are ten inequivalent F sites. In the first F site, F(7) is bonded in a distorted bent 150 degrees geometry to two equivalent Tb(3) atoms. In the second F site, F(8) is bonded to one K(1), one Tb(2), and two equivalent Tb(1) atoms to form distorted FKTb3 tetrahedra that share  a cornercorner with one F(4)K2Tb2 tetrahedra,  a cornercorner with one F(10)KTb3 tetrahedra, corners with two equivalent F(1)KTb3 tetrahedra, corners with four equivalent F(2)K2Tb2 tetrahedra, corners with five equivalent F(5)K2Tb2 tetrahedra,  an edgeedge with one F(8)KTb3 tetrahedra, edges with two equivalent F(2)K2Tb2 tetrahedra, and edges with two equivalent F(1)KTb3 tetrahedra. In the third F site, F(9) is bonded in a 2-coordinate geometry to one K(1), one Tb(2), and one Tb(3) atom. In the fourth F site, F(10) is bonded to one K(2), one Tb(2), and two equivalent Tb(3) atoms to form FKTb3 tetrahedra that share  a cornercorner with one F(4)K2Tb2 tetrahedra,  a cornercorner with one F(5)K2Tb2 tetrahedra,  a cornercorner with one F(8)KTb3 tetrahedra, corners with two equivalent F(2)K2Tb2 tetrahedra, corners with two equivalent F(1)KTb3 tetrahedra,  an edgeedge with one F(4)K2Tb2 tetrahedra, and edges with two equivalent F(1)KTb3 tetrahedra. In the fifth F site, F(1) is bonded to one K(2), one Tb(1), one Tb(2), and one Tb(3) atom to form FKTb3 tetrahedra that share  a cornercorner with one F(2)K2Tb2 tetrahedra,  a cornercorner with one F(5)K2Tb2 tetrahedra,  a cornercorner with one F(10)KTb3 tetrahedra,  a cornercorner with one F(8)KTb3 tetrahedra, corners with two equivalent F(4)K2Tb2 tetrahedra, corners with three equivalent F(1)KTb3 tetrahedra,  an edgeedge with one F(2)K2Tb2 tetrahedra,  an edgeedge with one F(5)K2Tb2 tetrahedra,  an edgeedge with one F(10)KTb3 tetrahedra, and  an edgeedge with one F(8)KTb3 tetrahedra. In the sixth F site, F(2) is bonded to two equivalent K(1), one Tb(1), and one Tb(3) atom to form FK2Tb2 tetrahedra that share  a cornercorner with one F(4)K2Tb2 tetrahedra,  a cornercorner with one F(1)KTb3 tetrahedra,  a cornercorner with one F(10)KTb3 tetrahedra, corners with two equivalent F(5)K2Tb2 tetrahedra, corners with two equivalent F(8)KTb3 tetrahedra, corners with five equivalent F(2)K2Tb2 tetrahedra,  an edgeedge with one F(2)K2Tb2 tetrahedra,  an edgeedge with one F(4)K2Tb2 tetrahedra,  an edgeedge with one F(5)K2Tb2 tetrahedra,  an edgeedge with one F(1)KTb3 tetrahedra, and  an edgeedge with one F(8)KTb3 tetrahedra. In the seventh F site, F(3) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Tb(3) atoms. In the eighth F site, F(4) is bonded to one K(1), one K(2), and two equivalent Tb(3) atoms to form FK2Tb2 tetrahedra that share  a cornercorner with one F(10)KTb3 tetrahedra,  a cornercorner with one F(8)KTb3 tetrahedra, corners with two equivalent F(2)K2Tb2 tetrahedra, corners with four equivalent F(1)KTb3 tetrahedra,  an edgeedge with one F(5)K2Tb2 tetrahedra,  an edgeedge with one F(10)KTb3 tetrahedra, and edges with two equivalent F(2)K2Tb2 tetrahedra. In the ninth F site, F(5) is bonded to one K(1), one K(2), and two equivalent Tb(1) atoms to form FK2Tb2 tetrahedra that share  a cornercorner with one F(10)KTb3 tetrahedra, corners with two equivalent F(1)KTb3 tetrahedra, corners with four equivalent F(2)K2Tb2 tetrahedra, corners with five equivalent F(8)KTb3 tetrahedra,  an edgeedge with one F(4)K2Tb2 tetrahedra,  an edgeedge with one F(5)K2Tb2 tetrahedra, edges with two equivalent F(2)K2Tb2 tetrahedra, and edges with two equivalent F(1)KTb3 tetrahedra. In the tenth F site, F(6) is bonded in a distorted bent 150 degrees geometry to one Tb(2) and one Tb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KTb2F7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.213
_cell_length_b   8.213
_cell_length_c   11.993
_cell_angle_alpha   59.614
_cell_angle_beta   59.614
_cell_angle_gamma   58.548
_symmetry_Int_Tables_number   1
_cell_volume   562.152
_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
  K  K0  1  0.763  0.763  0.479  1.0
  K  K1  1  0.267  0.267  0.152  1.0
  K  K2  1  0.733  0.733  0.848  1.0
  K  K3  1  0.237  0.237  0.521  1.0
  Tb  Tb4  1  0.240  0.760  0.500  1.0
  Tb  Tb5  1  0.760  0.240  0.500  1.0
  Tb  Tb6  1  0.740  0.740  0.179  1.0
  Tb  Tb7  1  0.260  0.260  0.821  1.0
  Tb  Tb8  1  0.266  0.740  0.817  1.0
  Tb  Tb9  1  0.740  0.266  0.817  1.0
  Tb  Tb10  1  0.260  0.734  0.183  1.0
  Tb  Tb11  1  0.734  0.260  0.183  1.0
  F  F12  1  0.381  0.854  0.263  1.0
  F  F13  1  0.854  0.381  0.263  1.0
  F  F14  1  0.370  0.838  0.582  1.0
  F  F15  1  0.838  0.370  0.582  1.0
  F  F16  1  0.995  0.995  0.238  1.0
  F  F17  1  0.606  0.606  0.748  1.0
  F  F18  1  0.894  0.894  0.575  1.0
  F  F19  1  0.005  0.669  0.000  1.0
  F  F20  1  0.669  0.005  0.000  1.0
  F  F21  1  0.394  0.394  0.252  1.0
  F  F22  1  0.995  0.331  1.000  1.0
  F  F23  1  0.331  0.995  1.000  1.0
  F  F24  1  0.146  0.619  0.737  1.0
  F  F25  1  0.619  0.146  0.737  1.0
  F  F26  1  0.324  0.676  0.000  1.0
  F  F27  1  0.676  0.324  0.000  1.0
  F  F28  1  0.005  0.005  0.762  1.0
  F  F29  1  0.605  0.605  0.413  1.0
  F  F30  1  0.997  0.655  0.241  1.0
  F  F31  1  0.655  0.997  0.241  1.0
  F  F32  1  0.003  0.345  0.759  1.0
  F  F33  1  0.345  0.003  0.759  1.0
  F  F34  1  0.387  0.387  0.882  1.0
  F  F35  1  0.106  0.106  0.425  1.0
  F  F36  1  0.395  0.395  0.587  1.0
  F  F37  1  0.162  0.630  0.418  1.0
  F  F38  1  0.630  0.162  0.418  1.0
  F  F39  1  0.613  0.613  0.118  1.0
[/CIF]
.