Flexible Fe(III)-based spin crossover materials through electropolymerisation

One new Fe(III) complex functionalised with an electropolymerisable unit was prepared and characterised. The complex (1) was obtained as a Cl- salt, with dichloromethane as solvate. The magnetic properties of the compound were determined using SQUID magnetometry, combined with temperature-dependent Raman. This analysis revealed that in its powdered form compound 1 displays an incomplete and very gradual spin crossover, predominantly remaining in the low spin state over the temperature range measured. The compound was tested for its efficacy in the fabrication of conducting polymers via electropolymerisation. Our findings indicate that compound 1 is efficient in the fabrication of spin crossover coatings. Additionally, the surface roughness of the polymers was found to vary with the addition of a surfactant, S-camphorsulfonic acid (CSA), during the electropolymerisation process. Interestingly, the polymers exhibit magnetic behaviours distinct from those of the powder forms, and the presence of CSA neither affects nor alters their magnetic properties. The polymers formed, both with and without CSA, demonstrate very gradual and complete spin crossover behaviour.