Magnetic susceptibility measurements were performed at a Quantum Design MPMS-XL-5 SQUID magnetometer. A field strength of 3 T was applied and a temperature range of 50 -400 K was used to determine the temperature dependency of the magnetism and the spin crossover behavior. Sweep mode was used for the five cycles with a cooling and heating rate of 5 K min -1 . The final measurement was performed in settle mode with an average cooling and heating rate of 0.5 K min -1 between 50 K and 300 K. The samples were prepared in gelatin capsules placed in a plastic straw. The measured values were corrected for the diamagnetism of the sample holder, the polymer matrix (measured values) and the ligand (tabulated Pascal constants).