- Letter
- Open Access
State selectivity in core ionization of methane
Phys. Rev. Research 7, L022021 – Published 22 April, 2025
DOI: https://doi.org/10.1103/PhysRevResearch.7.L022021
Abstract
A clear experimental signature of the population of the lowest triplet state of the methane dication is identified in a photoionization experiment. This state is populated only in valence ionization and is absent when the dication is formed by core ionization followed by Auger-Meitner decay. For valence ionization, the total internal energy of the fragment, formed during the deprotonation of , is evaluated. Notably, the distribution of this internal energy peaks at the same value regardless of the initially populated electronic state of . We find that excited electronic states of are predominantly populated with significant rovibrational excitation.
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