Laboratory astrochemistry: studying molecules under inter- and circumstellar conditions

In this paper, we outline recent developments in and the growing need for laboratory astrochemical measurements. After a short review on experimental methods, we focus primarily upon the utility of multi-electrode ion trapping methods for addressing key problems in reaction dynamics and their applications towards gaining a better understanding of the physicochemical driving forces behind compositional development in interstellar and circumstellar environments. Temperature variable trapping techniques, combined with lasers and molecular beams are unique tools for studying state specific reactions, for ion spectroscopy and for investigating the structure and stability of complex charged objects as a function of their internal energy. Particular emphasis is given to reactions with hydrogen atoms and molecules, H-D exchange leading to isotopic fractionation, problems in hydrocarbon ion chemistry and association chemistry in rarefied environments. In the outlook, we discuss the future needs in astrochemistry in order to pave the way towards understanding the next generation of sophisticated astronomical observations and to prepare for them.