This thesis explores the basic molecular magnetism of coordination complexes based on dianionic triazole ligand and first-row transition metals. In particular, the thermally-induced spin crossover (SCO) phenomenon of a triazole-based iron (II) trimer has been studied in different dimensions scales, from bulk to single molecule, ending with application-oriented surface engineering. On one side, the “macroscopic” SCO behavior has been modulated by changing the crystal packing and the connectivity between trimers with a cationic exchange strategy. On the other hand, SCO bistability has been found in highly diluted systems of FeII trimer, where the cooperative forces have been reduced down to molecular scale. Finally, nanometer film on fused silica substrate with intact SCO behavior have been fabricated. Furthermore, the miniaturization process have been pushed beyond nanometer size by growing well-ordered sub-monolayer of SCO complex on Au(111) substrate.
This SCO-active molecule opens up unique and promising options to build molecular magnetic switches operating around room temperature.