ÖPG-CMD Joint Meeting 2026

Low temperature ultraviolet photodissociation spectroscopy of [dAMP-H]$^-$

Sep 21, 2026, 12:15 PM

15m

HS 11.03 (University of Graz)

3) Contributed talk M14 - Experimental Studies of Negatively Charged Ions Mini-Colloquium

Speaker

Christian Sprenger (Universität Innsbruck)

Description

To deepen the understanding of photoexcitation of DNA by ultraviolet radiation, we performed a wavelength dependent photoabsorption study of the anionic deprotonated nucleotide [dAMP-H]$^-$.
Within the range of our study, between 240\,nm and 270\,nm, we were able to resolve multiple spectral features, that could not be resolved before. This was made possible by our 16-pole radiofrequency wire trap, which operates at a temperature of 3\,K.
Furthermore we analysed the yield of five ionic photofragments as a function of wavelength. Finally we determined the absolute photfragmentation cross section of [dAMP-H]$^-$, by performing a comparative measurement of the I$^-$ photodetachment cross section.
The results of these photodissociation measurements, published in [1], will be presented.

[1] C. Sprenger, S. J. M. White, M. Westermeier, G. Schöpfer, F. Dahlmann, U. Namangalam, S. Mohandas, S. Kumar S, E. S. Endres, M. Onćak, R. Wester, J. Phys. Chem. A, (2025) 129, 50, 11571-11579