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arXiv · 1608.06463

Desorption Dynamics of Rb_2 Molecules off the Surface of Helium Nanodroplets

A. Sieg·J. von Vangerow·F. Stienkemeier·O. Dulieu·M. Mudrich
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Abstract

The desorption dynamics of rubidium dimers (Rb_2) off the surface of helium nanodroplets induced by laser excitation is studied employing both nanosecond and femtosecond ion imaging spectroscopy. Similarly to alkali metal atoms, we find that the Rb_2 desorption process resembles the dissociation of a diatomic molecule. However, both angular and energy distributions of detected Rb_2^+ ions appear to be most crucially determined by the Rb_2 intramolecular degrees of freedom rather than by those of the Rb_2He_N complex. The pump-probe dynamics of Rb_2^+ is found to be slower than that of Rb^+ pointing at a weaker effective guest-host repulsion for excited molecules than for single atoms.

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A. Sieg, J. von Vangerow, F. Stienkemeier, O. Dulieu, M. Mudrich. 2016-08-23. Desorption Dynamics of Rb_2 Molecules off the Surface of Helium Nanodroplets. https://doi.org/10.1021/acs.jpca.6b05732

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