Isothiocyanat-Komplexe von Kupfer (II) mit quadratisch-planarer und tetragonal-pyramidaler Koordination: Struktur,Phasenumwandlungen und Redoxverhalten

Isothiocyanate Complexes of Copper(II) with Square-Planar and Tetragonal-Pyramidal Coordination: Structure, Phase Transitions, and Redox-Properties In dependence on the kind and size of the counter-cations Cu²⁺-ions form isothiocyanate complexes with different coordination number and geometry. The structures of compounds with square-planar coordination (NEt₄)₂Cu(NCS)₄] · CHCl₃ (brown): Space group 14/mmm, Z = 2; a = 1204.3(2) pm, c = 1154.2(3) pm] and with tetragonal-pyramidal polyhedra (NEt₄)₃Cu(NCS)₅] · SM (green, SM: unidentified solvent molecule): Space group P2₁/c, Z = 4; a = 1154.2(6) pm, b = 2291.6(10) pm, c = 1739.9(9) pm, ß = 95.98(5)°] are reported. The green complex transforms into a brown compound at room-temperature; the transformation is (partly) reversibly. Solutions of NCS-anions and Cu²⁺ are redox unstable. The structure of a resulting product: (PPh₄)₂Cu₂(NCS)₂] Space group C2/c, Z = 4; a = 1235.4(1) pm, b = 1347.1(2) pm, c = 2953.4(11) pm, ß = 99.36(2)°] with Cu(I) dimers and two bridging NCS^- ligands is also reported.