Gas-phase host-guest chemistry of dendritic viologens and molecular tweezers:: A remarkably strong effect on dication stability

(Figure Presented) Size does matter: Viologen dications (blue) substituted with dendrons form strong host-guest complexes with molecular tweezers (yellow) in solution and in the gas phase (see picture). Complexation even stabilizes dications which are intrinsically unstable as naked" species in the high vacuum of a mass spectrometer. A remarkably pronounced effect of dendrimer size on the stability of these dications switches their fragmentation between two mechanisms."