The compound described by Rb2KSiF7 crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to two equivalent F(3), two equivalent F(4), and two equivalent F(5) atoms to form RbF6 octahedra that share corners with two equivalent Si(1)F6 octahedra, corners with two equivalent Si(2)F6 octahedra, and corners with six equivalent Rb(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the second Rb site, Rb(2) is bonded in a 10-coordinate geometry to two equivalent F(1), two equivalent F(3), two equivalent F(5), and four equivalent F(2) atoms. K(1) is bonded in a 10-coordinate geometry to two equivalent F(2); two equivalent F(4); two F(5,5); and four equivalent F(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent F(4) and four equivalent F(1) atoms to form SiF6 octahedra that share corners with four equivalent Rb(1)F6 octahedra. The corner-sharing octahedral tilt angles are 69°. In the second Si site, Si(2) is bonded to two equivalent F(3) and four equivalent F(2) atoms to form SiF6 octahedra that share corners with four equivalent Rb(1)F6 octahedra. The corner-sharing octahedral tilt angles are 68°. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to one Rb(2), two equivalent K(1), and one Si(1) atom. In the second F site, F(2) is bonded in a distorted single-bond geometry to two equivalent Rb(2), one K(1), and one Si(2) atom. In the third F site, F(3) is bonded in a single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), and one Si(2) atom. In the fourth F site, F(4) is bonded in a single-bond geometry to two equivalent Rb(1), two equivalent K(1), and one Si(1) atom. In the fifth F site, F(5) is bonded to two equivalent Rb(1), two equivalent Rb(2), and two equivalent K(1) atoms to form corner-sharing FK2Rb4 octahedra. The corner-sharing octahedral tilt angles range from 0-26°. In the sixth F site, F(5) is bonded to two equivalent Rb(1), two equivalent Rb(2), and two equivalent K(1) atoms to form corner-sharing FK2Rb4 octahedra. The corner-sharing octahedral tilt angles range from 0-26°. is represented by the CIF card [CIF]
data_KRb2SiF7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.980
_cell_length_b   7.980
_cell_length_c   5.815
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.511
_symmetry_Int_Tables_number   1
_cell_volume   370.248
_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
  K  K0  1  0.195  0.195  0.500  1.0
  K  K1  1  0.805  0.805  0.500  1.0
  Rb  Rb2  1  0.000  0.500  0.000  1.0
  Rb  Rb3  1  0.500  0.000  0.000  1.0
  Rb  Rb4  1  0.694  0.306  0.500  1.0
  Rb  Rb5  1  0.306  0.694  0.500  1.0
  Si  Si6  1  0.000  0.000  0.000  1.0
  Si  Si7  1  0.500  0.500  0.000  1.0
  F  F8  1  0.894  0.106  0.788  1.0
  F  F9  1  0.106  0.894  0.788  1.0
  F  F10  1  0.392  0.392  0.789  1.0
  F  F11  1  0.608  0.608  0.789  1.0
  F  F12  1  0.106  0.894  0.212  1.0
  F  F13  1  0.894  0.106  0.212  1.0
  F  F14  1  0.608  0.608  0.211  1.0
  F  F15  1  0.392  0.392  0.211  1.0
  F  F16  1  0.652  0.348  0.000  1.0
  F  F17  1  0.348  0.652  0.000  1.0
  F  F18  1  0.153  0.153  0.000  1.0
  F  F19  1  0.847  0.847  0.000  1.0
  F  F20  1  0.000  0.500  0.500  1.0
  F  F21  1  0.500  0.000  0.500  1.0
[/CIF]
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The compound described by Rb2KSiF7 crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to two equivalent F(3), two equivalent F(4), and two equivalent F(5) atoms to form RbF6 octahedra that share corners with two equivalent Si(1)F6 octahedra, corners with two equivalent Si(2)F6 octahedra, and corners with six equivalent Rb(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the second Rb site, Rb(2) is bonded in a 10-coordinate geometry to two equivalent F(1), two equivalent F(3), two equivalent F(5), and four equivalent F(2) atoms. K(1) is bonded in a 10-coordinate geometry to two equivalent F(2); two equivalent F(4); two F(5,5); and four equivalent F(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent F(4) and four equivalent F(1) atoms to form SiF6 octahedra that share corners with four equivalent Rb(1)F6 octahedra. The corner-sharing octahedral tilt angles are 69°. In the second Si site, Si(2) is bonded to two equivalent F(3) and four equivalent F(2) atoms to form SiF6 octahedra that share corners with four equivalent Rb(1)F6 octahedra. The corner-sharing octahedral tilt angles are 68°. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to one Rb(2), two equivalent K(1), and one Si(1) atom. In the second F site, F(2) is bonded in a distorted single-bond geometry to two equivalent Rb(2), one K(1), and one Si(2) atom. In the third F site, F(3) is bonded in a single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), and one Si(2) atom. In the fourth F site, F(4) is bonded in a single-bond geometry to two equivalent Rb(1), two equivalent K(1), and one Si(1) atom. In the fifth F site, F(5) is bonded to two equivalent Rb(1), two equivalent Rb(2), and two equivalent K(1) atoms to form corner-sharing FK2Rb4 octahedra. The corner-sharing octahedral tilt angles range from 0-26°. In the sixth F site, F(5) is bonded to two equivalent Rb(1), two equivalent Rb(2), and two equivalent K(1) atoms to form corner-sharing FK2Rb4 octahedra. The corner-sharing octahedral tilt angles range from 0-26°. is represented by the CIF card [CIF]
data_KRb2SiF7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.980
_cell_length_b   7.980
_cell_length_c   5.815
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.511
_symmetry_Int_Tables_number   1
_cell_volume   370.248
_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
  K  K0  1  0.195  0.195  0.500  1.0
  K  K1  1  0.805  0.805  0.500  1.0
  Rb  Rb2  1  0.000  0.500  0.000  1.0
  Rb  Rb3  1  0.500  0.000  0.000  1.0
  Rb  Rb4  1  0.694  0.306  0.500  1.0
  Rb  Rb5  1  0.306  0.694  0.500  1.0
  Si  Si6  1  0.000  0.000  0.000  1.0
  Si  Si7  1  0.500  0.500  0.000  1.0
  F  F8  1  0.894  0.106  0.788  1.0
  F  F9  1  0.106  0.894  0.788  1.0
  F  F10  1  0.392  0.392  0.789  1.0
  F  F11  1  0.608  0.608  0.789  1.0
  F  F12  1  0.106  0.894  0.212  1.0
  F  F13  1  0.894  0.106  0.212  1.0
  F  F14  1  0.608  0.608  0.211  1.0
  F  F15  1  0.392  0.392  0.211  1.0
  F  F16  1  0.652  0.348  0.000  1.0
  F  F17  1  0.348  0.652  0.000  1.0
  F  F18  1  0.153  0.153  0.000  1.0
  F  F19  1  0.847  0.847  0.000  1.0
  F  F20  1  0.000  0.500  0.500  1.0
  F  F21  1  0.500  0.000  0.500  1.0
[/CIF]
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