The objective for the creation of a European network is to establish new relationships and strengthen existing ones between European researchers with complementary skills in the field of photochemistry, photo-physics, and applications of nanostructuration with photoactive molecules. The goal is to increase the knowledge of basic photo-mechanical properties and design supra-molecular systems of this family of reversible photoswitching molecules as azobenzene molecules in order to optimize their properties to develop new functional materials and implement this molecule into new application areas. Scientific innovations will emerge from the quantitative understanding of new developments and mechanisms of reversible photoinduced molecular movements. The potential impact regarding the implementation of advanced molecular systems to be exploited in the future of smart materials, molecular switches or biological processes activated by light. Scientific exchanges resulting from EU projects allow scientific interaction of chemists, physicists or biologists experimenter or theorist contributors to obtain new results in the field of physics to nano-technology advances in research fields such as information storage, optical control of bio-activities or energy conversion at the nanoscale. The interaction between applied and basic research groups, physicists and chemists, experimenters and theorists, biologists, the possibility of accessing different characterization techniques also will contribute to new and innovative designs of molecules or molecular systems photo-chemically activated. There are currently scientific links between contributors for future research projects. For example the LIA CNRS NAPOLI between the team of physicists from the University of Angers and the team of chemists at the Technical University of Wroclaw (Poland) develops nano-objects of engineering for azopolymère photonics and biology applications. The Wroclaw University of Technology and Tampere University of Technology in Finland interact and have joint publications. This is to extend and federate these collaborations between European actors of this research on these molecules on joint research projects and actions of skill networks. The projects covered will lead to the creation of a European COST network (Materials, Physics and Nanosciences (MPNS)), and calls for NMBP projects. For that the ANR support will ensure the synergy of ideas on joint research projects for the intermediate and final writings of the calls. The developed projects will establish widespread international relations by promoting a multidisciplinary collaborative research. The purpose of the network is to bring the European research community with knowledge in the field of molecular systems photoswitching to application areas for the development of current science challenges. There is no example to our knowledge of a European network COST around these molecules and European networks working on this molecular function are being completed or are not concerned by the interaction between different disciplinary fields of research. Moreover on this research field, Europe has a real leadership compare to the rest of the world and must continue to keep this position ahead of Japanese and Chinese teams.