ABSTRACT: One of the most versatile techniques available at present to obtain the spectra of cold molecular ions is based on ion storage in a cryogenic radiofrequency trap. Over the last few years, parallel activities in a several research groups have pushed the temperature of these devices to their lowest limits. Routine tagging of virtually any cation with helium atom(s) has led to a relatively straightforward route to obtain gas phase spectroscopic information on buffer gas cooled molecular ions. Moreover, a new sensitive method for detecting the absorption of a photon emerged. In this talk I will highlight some of our experimental work on the fullerenes and related molecular species of putative astrochemical interest, and discuss the implications. Time permitting, I will describe some of our current activities which involve combining non-standard methods for the synthesis and characterisation of complex molecular ions, and present some preliminary results on carbon cations Cn+ that thus far evaded spectroscopic investigation in the gas phase.
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