The material described by Cs2KSiF7 crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to two equivalent F(3), two equivalent F(4), and two equivalent F(5) atoms to form distorted CsF6 octahedra that share corners with two equivalent Si(1)F6 octahedra, corners with two equivalent Si(2)F6 octahedra, and corners with six equivalent Cs(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 0-68°. In the second Cs site, Cs(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 Cs(1)F6 octahedra. The corner-sharing octahedral tilt angles are 68°. 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 Cs(1)F6 octahedra. The corner-sharing octahedral tilt angles are 67°. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to one Cs(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 Cs(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 Cs(1), two equivalent Cs(2), and one Si(2) atom. In the fourth F site, F(4) is bonded in a single-bond geometry to two equivalent Cs(1), two equivalent K(1), and one Si(1) atom. In the fifth F site, F(5) is bonded to two equivalent Cs(1), two equivalent Cs(2), and two equivalent K(1) atoms to form corner-sharing FCs4K2 octahedra. The corner-sharing octahedral tilt angles range from 0-25°. In the sixth F site, F(5) is bonded to two equivalent Cs(1), two equivalent Cs(2), and two equivalent K(1) atoms to form corner-sharing FCs4K2 octahedra. The corner-sharing octahedral tilt angles range from 0-25°. is represented by the CIF card [CIF]
data_Cs2KSiF7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.235
_cell_length_b   8.235
_cell_length_c   6.067
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.761
_symmetry_Int_Tables_number   1
_cell_volume   411.480
_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
  Cs  Cs0  1  0.000  0.500  0.000  1.0
  Cs  Cs1  1  0.500  0.000  0.000  1.0
  Cs  Cs2  1  0.694  0.306  0.500  1.0
  Cs  Cs3  1  0.306  0.694  0.500  1.0
  K  K4  1  0.196  0.196  0.500  1.0
  K  K5  1  0.804  0.804  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  0.897  0.103  0.796  1.0
  F  F9  1  0.103  0.897  0.796  1.0
  F  F10  1  0.394  0.394  0.798  1.0
  F  F11  1  0.606  0.606  0.798  1.0
  F  F12  1  0.103  0.897  0.204  1.0
  F  F13  1  0.897  0.103  0.204  1.0
  F  F14  1  0.606  0.606  0.202  1.0
  F  F15  1  0.394  0.394  0.202  1.0
  F  F16  1  0.647  0.353  0.000  1.0
  F  F17  1  0.353  0.647  0.000  1.0
  F  F18  1  0.149  0.149  0.000  1.0
  F  F19  1  0.851  0.851  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 material described by Cs2KSiF7 crystallizes in the orthorhombic Cmmm space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to two equivalent F(3), two equivalent F(4), and two equivalent F(5) atoms to form distorted CsF6 octahedra that share corners with two equivalent Si(1)F6 octahedra, corners with two equivalent Si(2)F6 octahedra, and corners with six equivalent Cs(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 0-68°. In the second Cs site, Cs(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 Cs(1)F6 octahedra. The corner-sharing octahedral tilt angles are 68°. 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 Cs(1)F6 octahedra. The corner-sharing octahedral tilt angles are 67°. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to one Cs(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 Cs(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 Cs(1), two equivalent Cs(2), and one Si(2) atom. In the fourth F site, F(4) is bonded in a single-bond geometry to two equivalent Cs(1), two equivalent K(1), and one Si(1) atom. In the fifth F site, F(5) is bonded to two equivalent Cs(1), two equivalent Cs(2), and two equivalent K(1) atoms to form corner-sharing FCs4K2 octahedra. The corner-sharing octahedral tilt angles range from 0-25°. In the sixth F site, F(5) is bonded to two equivalent Cs(1), two equivalent Cs(2), and two equivalent K(1) atoms to form corner-sharing FCs4K2 octahedra. The corner-sharing octahedral tilt angles range from 0-25°. is represented by the CIF card [CIF]
data_Cs2KSiF7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.235
_cell_length_b   8.235
_cell_length_c   6.067
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.761
_symmetry_Int_Tables_number   1
_cell_volume   411.480
_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
  Cs  Cs0  1  0.000  0.500  0.000  1.0
  Cs  Cs1  1  0.500  0.000  0.000  1.0
  Cs  Cs2  1  0.694  0.306  0.500  1.0
  Cs  Cs3  1  0.306  0.694  0.500  1.0
  K  K4  1  0.196  0.196  0.500  1.0
  K  K5  1  0.804  0.804  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  0.897  0.103  0.796  1.0
  F  F9  1  0.103  0.897  0.796  1.0
  F  F10  1  0.394  0.394  0.798  1.0
  F  F11  1  0.606  0.606  0.798  1.0
  F  F12  1  0.103  0.897  0.204  1.0
  F  F13  1  0.897  0.103  0.204  1.0
  F  F14  1  0.606  0.606  0.202  1.0
  F  F15  1  0.394  0.394  0.202  1.0
  F  F16  1  0.647  0.353  0.000  1.0
  F  F17  1  0.353  0.647  0.000  1.0
  F  F18  1  0.149  0.149  0.000  1.0
  F  F19  1  0.851  0.851  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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