Spin crossover in mixed-anion Fe(NH₂trz)₃(BF₄)(SiF₆)_{0 .5} crystalline rod-shaped particles: the strength of the solid-liquid post synthetic modification

A pure mixed-anion Fe(NH(2)trz)(3)(BF4)(SiF6)(0.5) spin crossover complex is obtained implementing a solid-liquid post synthetic modification approach from the Fe(NH(2)trz)(3)(BF4)(2) parent complex. This method allows obtaining highly crystalline powder samples incorporating homogeneous micrometric (1 & mu;m long) rod-shaped particles. This compound presents an abrupt spin crossover behaviour with a narrow (10 K) hysteresis loop centred just above room temperature (320 K) which makes it very interesting for future integration into devices for various applications.