Femtosecond photoexcitation dynamics inside a quantum solvent.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30275442.
- Also identified by DOI 10.1038/s41467-018-06413-9 and PMC identifier 6167364.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The observation of chemical reactions on the time scale of the motion of electrons and nuclei has been made possible by lasers with ever shortened pulse lengths. Superfluid helium represents a special solvent that permits the synthesis of novel classes of molecules that have eluded dynamical studies so far. However, photoexcitation inside this quantum solvent triggers a pronounced response of the solvation shell, which is not well understood. Here, we present a mechanistic description of the solvent response to photoexcitation of indium (In) dopant atoms inside helium nanodroplets (He<sub>N</sub>), obtained from femtosecond pump-probe spectroscopy and time-dependent density functional theory simulations. For the In-He<sub>N</sub> system, part of the excited state electronic energy leads to expansion of the solvation shell within 600 fs, initiating a collective shell oscillation with a period of about 30 ps. These coupled electronic and nuclear dynamics will be superimposed on intrinsic photoinduced processes of molecular systems inside helium droplets.