Magnetic properties of two trimeric Cu(II) complexes with ferromagnetic intratrimer interaction

Abstract Two trimeric Cu(II) complexes CuEtBz and CuBuBz have been studied by means of magnetization, ac susceptibility and EPR methods. The experimental data have been interpreted in terms of a total spin Hamiltonian. The obtained results confirm ferromagnetic intratrimer coupling for both substances. CuEtBz can be well described as a superparamagnet composed of non- (or very weakly) interacting species with a spin value close to 3/2. A large zero-field splitting, attributed to anisotropic exchange, has been for this compound. CuBuBz shows an interesting nonlinear behaviour at low temperatures as a function of magnetic field which seems to be connected with intertrimer interactions.