Outlook and developments
Spin Crossover - Switching the spin state of materials

Numerous applications have been mentioned throughout this article. The color change makes these compounds attractive for anything from visual sensors and detectors (of shock, infrared light, gases, solvents, etc.) to intelligent pigments [REV 1 530] . The associated memory effect is obviously a major asset for deferred reading (shock detection on aircraft cabins, cold chain breakage, etc.). Variations in mechanical properties are also envisaged for mechanical actuators and piezo-sensitive systems. Coupled with other functions (luminescence, plasmon resonance, ferroelectricity, electrical conduction, chirality, nonlinear optics, etc.), these properties open up a wide range of applications for these multifunctional systems, as demonstrated by OliKrom's work on intelligent pigments.