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Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Single and multiple photoionisation of H2S by 40-250 eV photons
J H D Eland1, R F Fink, P Linusson
1Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK.
Physical Chemistry Chemical Physics : PCCP
|September 17, 2011
Summary
Multi-electron coincidence measurements reveal molecular field effects on the Auger process in hydrogen sulfide (H2S) photoionization. Unexpected intensity distributions were observed in triple ionization spectra.
Area of Science:
- Atomic and Molecular Physics
- Quantum Chemistry
- Spectroscopy
Background:
- The Auger process is crucial for understanding electronic relaxation in molecules.
- Investigating molecular field effects provides insights into electron correlation and molecular structure.
- Previous studies on H2S photoionization have not fully detailed multi-electron dynamics.
Purpose of the Study:
- To quantify molecular field effects on the Auger process in H2S photoionization.
- To analyze the spectra of core-valence double ionization and subsequent Auger decays.
- To determine the onset energy for triple ionization in H2S.
Main Methods:
- Multi-electron coincidence measurements were performed.
- Photoionization experiments were conducted at photon energies ranging from 40 to 250 eV.
- Analysis of triply charged product spectra from Auger decays of core-valence states.
Main Results:
- Measurements quantified molecular field effects on the Auger process, showing good agreement with theory.
- Spectra of core-valence double ionization of H2S were presented and analyzed.
- Triple ionization via double Auger decay from 2p hole states exhibited surprising intensity distributions and significant cascade contributions.
Conclusions:
- Molecular field effects play a role in H2S photoionization, particularly in the Auger process.
- Cascade processes significantly contribute to triple ionization, even involving dissociation.
- The onset of triple ionization for H2S was determined to be 61 ± 0.5 eV.
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