Ricerc@Sapienza

Raman spectroscopy is moreover a fast and accurate vibrational technique that allows for chemical identification complementing Infrared spectroscopy. A- Solid State Physics and Nanomaterials Raman spectroscopy has become the fundamental characterization tool for carbon-based materials and other 2D compounds. Indeed, the use of Raman spectroscopy has allowed the understanding of the phonons of graphene and of some aspects of their interaction with the electrons. We focus on the Raman spectra of 2D van der Waals materials in order to study electron-phonon interaction in these systems. B. FT Raman spectroscopy of manuscripts and cultural heritage The radiation at wavelengths between 0.7 and 1.5 microns (Near Infrared, NIR) is particularly suitable for the analysis of deep layers, since pigments and binders do not show intense absorption in these regions of the spectrum and the radiation interacts more with the underlying layers. Moreover, the absorption of radiation by organic matter is the minimum possible, being the NIR at great spectral distance both from the vibrational lines of the medium IR, and from the electronic transitions of the visible and UV. While this would guarantee the least possible damage to the artwork, the lack of spectral fingerprints in this spectral region does not allow for chemical recognition unless a spectroscopic technique such as Raman is employed. In this technique, the spectral fingerprints are detected by the energy difference of the photon of an excitation laser and therefore the real radiation always remains in the NIR range, with obvious advantages of transmission through the organic matter both for the study in depth and for the elimination of laser heating. C. FT-Raman study of fluorescent and photo active proteins Long-wavelength excitation of Raman scattering offers unprecedented opportunities for the study of chromophoric proteins especially because the limitations imposed by fluorescence and photolability of photoactive proteins are circumvented. In particular we will focus on two different classes of photo-active proteins: i) Engineered ferritin to be used as nanocarriers for the targeted delivery of drugs and as imaging agents; ii) photoactive rhodopsin proteins.