Electron-Driven Molecular Processes Induced in Biological Systems by Electromagnetic and Other Ionizing Sources

We describe, and analyse in some detail, a selection of the most recent theoretical and computational models which attempt to explain, at the molecular level, the dynamics of metastable negative ion formation from biological molecules in the gas-phase. Such Transient Negative Ions (TNIs) are related to the nanoscopic nuclear dynamics presiding over the occurrence of irreversible damage in the biosystems through the many possible pathways leading to dissociative attachment decay of the initial TNI. We will review the theoretical approach we adopted to study electron-molecule collision as applied to systems of biological interest. The connection between the spatial symmetry of the metastable anion and its role during the dissociative electron attachment event is also discussed and analysed through several examples.