Solid State Astrochemistry

The fundamentals of astrochemistry in the gas phase are relatively well established, in contrast to the special relevance attributed to processes involving interstellar dust grains – the solid component of matter diffused among the stars. This work presents the state-of-the-art in relation to the ways grains interact with gases, the catalytic role played by dust that allows key molecular species (H2 as well as many complex, possibly prebiotic species) to be formed on its surface – which cannot be obtained efficiently by any other mechanisms, and the interaction between solids (dust grains, icy mantles, cometary nuclei, satellites of the giant planets and minor bodies in the Solar system) in space and energetic agents such as UV photons and fast particles. The presence and importance of PAH, which may represent the smallest component of the grains, is considered in relation to possible astrobiological pathways and the ever-present mystery of the ubiquitous presence of Diffuse Interstellar Bands and their carriers.