Theoretical Investigation of The X-Ray Stark Effect in Small Molecules

TL;DR

This paper presents a theoretical study of the X-ray Stark effect in small molecules, analyzing how electric fields influence their x-ray absorption spectra and electronic structures, highlighting potential applications in molecular spectroscopy.

Contribution

It introduces a comprehensive theoretical framework for understanding the X-ray Stark effect in small molecules, emphasizing the roles of molecular orbitals and geometry in spectral shifts.

Findings

Both valence and core orbitals contribute to spectral shifts.

Identified trends linking electronic structure features to absorption changes.

Potential of X-ray Stark spectroscopy for sub-molecular environmental studies.

Abstract

We have studied the Stark effect in the soft x-ray region for various small molecules by calculating the field-dependent x-ray absorption spectra. This effect is explained in terms of the response of molecular orbitals (core and valence), the molecular dipole moment, and the molecular geometry to the applied electric field. A number of consistent trends are observed linking the computed shifts in absorption energies and intensities with specific features of the molecular electronic structure. We find that both the virtual molecular orbitals (valence and/or Rydberg) as well as the core orbitals contribute to observed trends in a complementary fashion. This initial study highlights the potential impact of x-ray Stark spectroscopy as a tool to study electronic structure and environmental perturbations at a sub-molecular scale.