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Updated: Apr 29, 2026
Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Cooling dynamics of photoexcited C6(-) and C6H(-)
G Ito1, T Furukawa1, H Tanuma1
1Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan.
Abstract:
We report conclusive evidence of an efficient cooling mechanism via the electronic radiative transitions of hot small molecular anions isolated in vacuum. We stored C6(-) and C6H(-) in an ion storage ring and observed laser-induced electron detachment with delays up to several milliseconds. The terminal hydrogen atom caused a drastic change in the decay profiles. The decay of photoexcited C6H(-) is slow and nonexponential, which can be explained by depletion cooling, whereas that for C6(-) occurs extremely fast, on a time scale below 0.1 ms and can only be explained by electronic radiative cooling via low-lying electronic excited states.
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