High Energy Metal-Based Compounds: The Road to Perazametallocene

This Proposal lies at the interface of synthetic chemistry, materials, and energy.It is aimed at synthesis and fundamental understanding of molecular structure and reactivity of high energy compounds, with the ultimate goal of producing chemical systems which could store energy very efficiently.The Applicant was fortunate enough to be able to make a whole series of very unusual if not unique compounds, the majority of which contained a very high number of coordinated azide groups. It is this work which will act as a springboard for launching this new project.Energy need and storage poses a constant scientific challenge to modern world. Thanks to the work of two eminent chemists, Berthold Schwarz (15th century) and Alfred Nobel (19th century), we have known for many years that large amounts of energy can be stored in small quantities of particular materials. Depending on the intended use of energy a plethora of ways for its storage can be chosen, such as spiral springs, water reservoirs at high altitude, nuclear fuel, car fuel, or rocket propellant. Chemical energy storage often has a clear advantage when it comes to very small size, very rapid energy release and simplicity of application. The energy density often is the property that can be easily maximised in such compounds. A major challenge that must be addressed in chemical energy storage is how to combine high energy density and controlled energy release; thus, many high energy density compounds decompose unpredictably and violently.In the quest for new compounds that are capable of possessing a high energy density, systems with high content of nitrogen are especially promising. Furthermore, they have the potential to generate energy without: (i) requiring oxygen and (ii) releasing carbon dioxide or other greenhouse gases. The energy storage capacity of such compounds originates from the formation of the non-toxic and chemically inert nitrogen gas (N2) during decomposition; this molecule possesses an N=N triple bond that is very stable so its formation releases a considerable amount of energy.This Proposal addresses the question of safe, green , energy storage materials in a conceptually new way. The proposed solution is based on a hybrid between organometallic and main group element chemistry of nitrogen rich compounds, aided by advanced spectroscopy and complemented by theoretical calculations. Three interlinked strands of fundamental research are proposed in the quest for compounds of high energy density as energy stores, including:(i) The unique strategy for synthesis of the long-sought-after perazametallocenes in the quest for materials of high energy density as energy stores, based on an implementation of physico-chemical methods as opposed to all-chemical strategies.(ii) Synthesis of a range of new polyazides as high energy molecules, understanding the factors governing lability and unravelling their photochemistry (iii) Polyazides under high pressure in the search for methods increasing the energy density und understanding the structural and potential chemical changes occurring.The outlined research, if successful, will initiate the development of new classes of binary nitrogen compounds and the field of photoreactivity of nitrogen rich compounds. It will provide pivotal understanding of the reasoning behind lability of these compounds and thus enable us to control energy release from promising high energy density materials. It will contribute to the unravelling of structural changes of high energy compounds under ultra high pressure, facilitate the development of high energy storage materials, afford fundamental understanding of previously unknown classes of compounds, and drive science and technology in new areas.