Time-resolved Intramolecular Photoelectron Diffraction (TIPD) of Ions in the Gas-phase
Lead Research Organisation:
Durham University
Department Name: Chemistry
Abstract
Being able to probe structural (electronic and geometric) change on the timescale of atomic motion
(femtoseconds) offers the most direct route to understanding the structure-function relationship in
chemistry, which underpins much of modern technology. Here, we propose the conceptually novel
method, Time-resolved Intramolecular Photoelectron Diffraction (TIPD), in which photoelectrons are
diffracted from negatively-charged functional groups in a mass-selected gas-phase polyanion. The
measured interferogram contains structural information about the location of charge-sites relative to
the molecular orbital from which an electron is detached. It can be measured with sub-100 fs
resolution to enable real-time probing of photoinduced processes including charge-transfer
processes and structural transformations in, for example, proteins and conducting polymers.
(femtoseconds) offers the most direct route to understanding the structure-function relationship in
chemistry, which underpins much of modern technology. Here, we propose the conceptually novel
method, Time-resolved Intramolecular Photoelectron Diffraction (TIPD), in which photoelectrons are
diffracted from negatively-charged functional groups in a mass-selected gas-phase polyanion. The
measured interferogram contains structural information about the location of charge-sites relative to
the molecular orbital from which an electron is detached. It can be measured with sub-100 fs
resolution to enable real-time probing of photoinduced processes including charge-transfer
processes and structural transformations in, for example, proteins and conducting polymers.
Organisations
People |
ORCID iD |
| Jan Verlet (Principal Investigator) |
Publications
Gibbard JA
(2021)
Photoelectron spectroscopy of the protoporphyrin IX dianion.
in Physical chemistry chemical physics : PCCP
Gibbard JA
(2022)
Kasha's Rule and Koopmans' Correlations for Electron Tunnelling through Repulsive Coulomb Barriers in a Polyanion.
in The journal of physical chemistry letters
| Description | This project aimed to develop a deeper understanding of so-called Repulsive Coulomb Barriers (RCBs) in gas-phase polyanions, and then to use this knowledge to develop methods to understand electron emission from polyanions and use that to relate the measurable photoelectron spectrum and angular distribution to the structure and dynamics of the polyanion. To this end, we have performed experiments aimed at understanding the dynamics of electron emission from a dianion and have found rather unexpected and surprising results that show that electron emission is in competition with internal conversion. We have uncovered a electronic version of Kasha's Rule applied to fluorescence. We have also performed computational work to compute the RCB (which has turned out to be much more complicated than anticipated) and are working towards understanding the electronic dynamics of the remaining anion following electron emission from a dianion. |
| Exploitation Route | The progress so far has been on a basic science level in terms of understanding RCBs and electron emission dynamics. Our work will be of interest to the chemical dynamics community and ultrafast spectroscopy community. |
| Sectors | Other |
| URL | http://www.verlet.net |