Mapping the Spin State in Spin-Crossover Complex Assemblies: Current-Imaging Tunnelling Spectroscopy (CITS)



This microreview highlights recent techniques used to determine the spin state at or around room temperature in nanoscale objects composed of iron(II) spin-crossover complexes. Complexes have been studied in the form of thin films, nanoparticles, single molecules or oligomolecular aggregates. Three approaches are presented: Surface plasmon polariton resonance in films on Ti/Au substrates, the determination of single-particle current–voltage characteristics between gold electrodes, and current-imaging tunnelling spectroscopy performed on highly oriented pyrolytic graphite-adsorbed strings of oligonuclear, bead-like complex aggregates.