The material described by K2CuF4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. K(1) is bonded in a 9-coordinate geometry to four equivalent F(2) and five equivalent F(1) atoms. Cu(1) is bonded to two equivalent F(1) and four equivalent F(2) atoms to form corner-sharing CuF6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent F sites. In the first F site, F(1) is bonded to five equivalent K(1) and one Cu(1) atom to form distorted FK5Cu octahedra that share corners with five equivalent F(1)K5Cu octahedra, corners with twelve equivalent F(2)K4Cu2 octahedra, edges with eight equivalent F(1)K5Cu octahedra, and faces with four equivalent F(2)K4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-56°. In the second F site, F(2) is bonded to four equivalent K(1) and two equivalent Cu(1) atoms to form FK4Cu2 octahedra that share corners with two equivalent F(2)K4Cu2 octahedra, corners with twelve equivalent F(1)K5Cu octahedra, edges with two equivalent F(2)K4Cu2 octahedra, faces with four equivalent F(2)K4Cu2 octahedra, and faces with four equivalent F(1)K5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-56°. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2CuF4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.086
_cell_length_b   4.086
_cell_length_c   6.967
_cell_angle_alpha   107.094
_cell_angle_beta   107.094
_cell_angle_gamma   89.986
_symmetry_Int_Tables_number   1
_cell_volume   105.800
_cell_formula_units_Z   1
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  0.358  0.358  0.716  1.0
  K  K1  1  0.642  0.642  0.284  1.0
  Cu  Cu2  1  1.000  1.000  1.000  1.0
  F  F3  1  0.153  0.153  0.305  1.0
  F  F4  1  0.500  1.000  0.000  1.0
  F  F5  1  0.847  0.847  0.695  1.0
  F  F6  1  0.000  0.500  0.000  1.0
[/CIF]
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The material described by K2CuF4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. K(1) is bonded in a 9-coordinate geometry to four equivalent F(2) and five equivalent F(1) atoms. Cu(1) is bonded to two equivalent F(1) and four equivalent F(2) atoms to form corner-sharing CuF6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent F sites. In the first F site, F(1) is bonded to five equivalent K(1) and one Cu(1) atom to form distorted FK5Cu octahedra that share corners with five equivalent F(1)K5Cu octahedra, corners with twelve equivalent F(2)K4Cu2 octahedra, edges with eight equivalent F(1)K5Cu octahedra, and faces with four equivalent F(2)K4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-56°. In the second F site, F(2) is bonded to four equivalent K(1) and two equivalent Cu(1) atoms to form FK4Cu2 octahedra that share corners with two equivalent F(2)K4Cu2 octahedra, corners with twelve equivalent F(1)K5Cu octahedra, edges with two equivalent F(2)K4Cu2 octahedra, faces with four equivalent F(2)K4Cu2 octahedra, and faces with four equivalent F(1)K5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-56°. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2CuF4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.086
_cell_length_b   4.086
_cell_length_c   6.967
_cell_angle_alpha   107.094
_cell_angle_beta   107.094
_cell_angle_gamma   89.986
_symmetry_Int_Tables_number   1
_cell_volume   105.800
_cell_formula_units_Z   1
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  0.358  0.358  0.716  1.0
  K  K1  1  0.642  0.642  0.284  1.0
  Cu  Cu2  1  1.000  1.000  1.000  1.0
  F  F3  1  0.153  0.153  0.305  1.0
  F  F4  1  0.500  1.000  0.000  1.0
  F  F5  1  0.847  0.847  0.695  1.0
  F  F6  1  0.000  0.500  0.000  1.0
[/CIF]
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