Imaging Molecular Structure through Femtosecond Photoelectron Diffraction on Aligned and Oriented Gas-Phase Molecules

TL;DR

This study advances femtosecond time-resolved photoelectron diffraction techniques on gas-phase molecules, combining optical lasers and X-ray free-electron lasers to analyze molecular structures with high temporal resolution.

Contribution

It demonstrates experimental progress in measuring photoelectron angular distributions from laser-aligned molecules using femtosecond diffraction methods.

Findings

Successful measurement of photoelectron angular distributions for aligned molecules

Analysis of laser pulse effects on electron and ion spectra

Discussion on implications for future time-resolved diffraction experiments

Abstract

This paper gives an account of our progress towards performing femtosecond time-resolved photoelectron diffraction on gas-phase molecules in a pump-probe setup combining optical lasers and an X-ray Free-Electron Laser. We present results of two experiments aimed at measuring photoelectron angular distributions of laser-aligned 1-ethynyl-4-fluorobenzene (C8H5F) and dissociating, laseraligned 1,4-dibromobenzene (C6H4Br2) molecules and discuss them in the larger context of photoelectron diffraction on gas-phase molecules. We also show how the strong nanosecond laser pulse used for adiabatically laser-aligning the molecules influences the measured electron and ion spectra and angular distributions, and discuss how this may affect the outcome of future time-resolved photoelectron diffraction experiments.