Molecole fotocromiche come macchine molecolari

Light-driven unidirectional molecular motors have attracted a great interest not only from a fundamental point of view but also for their potential applications in medicine, materials science and information technology. The first light-driven single molecule motor was reported by Feringa in 1999, being a unidirectional rotor based on a chiral overcrowded olefin. This work opened the door to the artificial conversion of light energy into mechanical motion through rotation around a C=C bond. Numerous investigations were subsequently carried out, with the goals of increasing the rotational speed and tuning the activation wavelength of these molecular motors, and many new kinds of unidirectional light-driven molecular motors have emerged over the last two decades. In this thesis we will discuss the basic principles of unidirectional motion, the reaction mechanism at the basis of the rotors and we will outline the most relevant developments and applications in the field.