Quantum Science Colloquium - Henrik Stapelfeldt, Department of Chemistry, and Simon Høgh Albrechtsen, Department of Physics and Astronomy, Aarhus University
Oplysninger om arrangementet
Title: The primary steps of ion solvation
We will present recent experimental results that have enabled us to observe the solvation dynamics of a single alkali cation ion in liquid helium with atomic resolution and on the natural femtosecond time scale.
A single Na+ or Li+ ion is created instantly at the surface of a liquid He nanodroplet and we measured in real time the gradual attachment of individual He atoms to the ion. We found that Na+ binds the first eight He atoms with a constant rate of one atom per 0.7 ps. This agrees with the outcome of time-dependent DFT simulations of the Na+ solvation process. The time-dependent yields of the Na+(Hen) and Li+(Hen) ion complexes recorded point to that solvation occurs not solely through sequential binding of He atoms but also by several He atoms attaching to the ion simultaneously. The atomic-scale information from our method opens novel possibilities for time-resolved measurements of cation-molecule complex formation.