Die Neubestimmung der K2CuF4-Struktur

Redetermination of the K₂CuF₄ Structure The structure of K₂CuF₄ was redetermined by x-rays. An enlarged tetra-gonal unit cell of dimensions a = 5.858, c = 25.42 Å was found. The refinement in spacegroup D–I4c2 yielded R = 0.06. Contrary to former findings the JAHN-TELLER- distortion of the CuF₆-octahedra corresponds to a tetragonal elongation with distances Cu–F = 1.92 Å (4 ×) and 2.22 Å(2×).