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Synopsis This work relies on complementary theoretical and experimental studies of the processes induced by ion-furan collisions. Results of the Molecular Dynamics simulations and exploration of the energy profiles combined with coincidence mass spectrometry provide complete picture of the fragmentation of furan dication.

Synopsis Here we report on experimental studies of the collisions between butadiene clusters and three different ionizing radiation sources: 70 eV electrons, 270 nm photons and 3 keV Ar+ ions. New molecular species are produced by growth mechanism inside of clusters.

Total cross section (TCS) for low-energy electron scattering from formic acid molecules has been measured using electrostatic electron spectrometer working in linear transmission mode. Two local maxima centered around 1.7 eV and 7.8 eV have been observed and associated with resonant scattering processes.

The fragmentation of 2Br-, 2Cl- and 5Br-pyrimidine following direct valence photoionization or inner shell excitation and decay has been studied by electron-ion coincidence experiments. The results show that the fragmentation is strongly selective on the final singly charged ion state and the dominant fragmentation patterns correlate to the nearest appearance potential.

Systematic molecular dynamics simulations based on the self-consistent charge density functional tight-binding method have been performed for the molecular collisions inside clusters of fullerene molecules, after prompt atom knockouts by the keV ions. The thermodynamic and kinetic stabilities, as well as the bonding features, have been investigated for the most stable dumbbell dimers C+118, C+119 and C+120

In this work we study statistical fragmentation of Polycyclic Aromatic Hydrocarbon (PAH) molecules following collisions with keV ions. Dissociation and transition state energies for H- and H2-emissions from PAHs have been calculated and a simple electronic stopping model has been used to calculate collision-induced internal PAH temperatures. We find that H2 may be formed efficiently from pristine PAHs for internal ion temperatures above 2200 K.

The CIRIL: 30 years of interdisciplinary research at GANIL meeting was held in Caen, France, in October 2013. The meeting provided an excellent opportunity to present the research performed with ion beams delivered by the GANIL facility (Grand Accelerateur National d'Ions Lourds, Caen, France). This proceedings volume comprises a series of reviews from different disciplines (physics, chemistry, biology, medicine, etc) of the results obtained with GANIL ion beams. Unfortunately, the issue is missing two major research domains concerning the induced damage in metals and insulators. Therefore, we refer the interested readers to the following publications: metals [1] and insulators [2].

We report experimental indications of chemical reactions inside clusters of pyrene (C16H10) molecules following collisions with 11.25 keV He+ - and 12.0 keV Ar2+ ions. It appears that bond-forming reactions are more likely with the heavier projectile. We have also performed classical molecular dynamics simulations of these processes where we treat the interaction between the projectiles and all atoms in the cluster as well as non-dispersive and dispersive forces between all atoms in the cluster before, during and after the collision. The time step is typically 10−17 s and the total simulation time 1 picosecond. The simulations were performed for a fixed cluster size with 36 pyrene molecules, although there is a broad range of cluster sizes in the experiment. Still, there is good qualitative agreement between the experimental and the simulated mass spectra exhibiting reaction products with masses between those of the C16H10- monomer and dimer in both cases. Additional studies of the influence of the projectile charge and mass is planned as well as simulations on longer time scales and as functions of cluster size.

International audience; We report on collisions of highly charged Xe20+ ions with weakly bound clusters of water molecules and water/adenine mixtures. Singly and doubly charged water clusters are observed in the size range of n=1 to 65 and n=49 to 61, respectively. In contrast to other comparable systems, the dominant monomer fragment (H3O+) is formed with very low kinetic energy, hence indicating that it is formed by evaporation processes. Larger fragments are produced with larger kinetic energies due to charge-separating processes. Furthermore, water clusters are found to be protonated, only a very small amount of the non protonated dimer (H2O)(2)(+) is observed. Excited mixed adenine/water clusters fragment by the loss of the surrounding water molecules, thus, adenine fragments are formed without water molecules attached. In addition, the adenine monomer is found to be partly protonated.

Interaction between slow multiply charged ions and small to medium-size neutral water clusters is investigated. Strong projectile charge dependence is found for all of the fragmentation patterns. A variation of the projectile charge dramatically changes the proportion of multi-electron removal, the fragment kinetic energies as well as the mean size of the emitted fragments. First results for highly charged ion - water cluster ion collisions will also be presented.

With highly charged ions at low energy, molecules can be ionised on fs timescale at large distances without appreciable energy transfer. Their interaction with small amino acids leads to the fragmentation by cleavage of the weakest bond similarly to the other radiation induced fragmentation. A protective effect of the environment is observed when the molecules are embedded in a cluster of amino acids. The molecular cluster acts as a buffer dissipating the excess energy.

The 1st Nano-IBCT Conference entitled 'Radiation Damage in Biomolecular Systems: Nanoscale Insights into Ion Beam Cancer Therapy' was held in Caen, France, in October 2011. The Meeting was organised in the framework of the COST Action MP1002 (Nano-IBCT) which was launched in December 2010 (http://fias.uni-frankfurt.de/nano-ibct). This action aims to promote the understanding of mechanisms and processes underlying the radiation damage of biomolecular systems at the molecular and nanoscopic level and to use the findings to improve the strategy of Ion Beam Cancer Therapy. In the hope of achieving this, participants from different disciplines were invited to represent the fields of physics, biology, medicine and chemistry, and also included those from industry and the operators of hadron therapy centres. Ion beam therapy offers the possibility of excellent dose localization for treatment of malignant tumours, minimizing radiation damage in normal healthy tissue, while maximizing cell killing within the tumour. Several ion beam cancer therapy clinical centres are now operating in Europe and elsewhere. However, the full potential of such therapy can only be exploited by better understanding the physical, chemical and biological mechanisms that lead to cell death under ion irradiation. Considering a range of spatio-temporal scales, the proposed action therefore aims to combine the unique experimental and theoretical expertise available within Europe to acquire greater insight at the nanoscopic and molecular level into radiation damage induced by ion impact. Success in this endeavour will be both an important scientific breakthrough and give great impetus to the practical improvement of this innovative therapeutic technique. Ion therapy potentially provides an important advance in cancer therapy and the COST action MP1002 will be very significant in ensuring Europe's leadership in this field, providing the scientific background, required data and mechanistic insight which are indispensable for the optimization of this new therapy. The conference gathered 115 participants originating from 28 countries and addressed a large number of highly relevant aspects concerning ion propagation in biological matter, the production of secondary particles along the ion tracks as electrons, holes and radicals, and their propagation in the biomolecular medium. In particular, the attack of DNA molecules and proteins by electrons and free radicals, the relative importance of direct and indirect damage processes as well as the role of the environment were discussed. Not only were fundamental mechanisms and processes elucidated, but radiobiological scale effects, multi-scale approaches and recent advances in the theoretical description of the underlying complex phenomena were also presented. Aspects linked to the energy deposition (LET), the characteristics of the Bragg peak and new techniques of dosimetry and radiolysis were highlighted. Furthermore, methods for increasing the therapy efficiency by using radio sensitizers and the state-of-the-art of defining precise patient treatment plans, identifying the clinical benefits of this type of therapy, were also addressed. We would like to thank all participants for the lively exchange of ideas and results, thus making this conference a very fruitful event. Furthermore, we appreciate the financial support of the sponsors of this conference, in particular of the COST Action MP1002 financed by ESF. We would also like to express our thanks to all authors of these proceedings, as well as to the reviewers for their time, efforts and recommendations made during the preparation of this volume. Finally, many thanks to U G Huber for a careful proof-read of this manuscript. We look forward to the 2nd Nano-IBCT Conference, which will be held in spring 2013. Caen, 15 March 2012 Bernd A Huber, Christiane Malot, Alicja Domaracka and Andrey V Solov'yov The Editors The PDF also contains details of the Conference Committees and Sponsors and a list of participants.