Chiral Four-Wave-Mixing signals with circularly-polarized X-ray pulses

TL;DR

This paper develops a theoretical framework for analyzing chiral four-wave-mixing signals generated by circularly-polarized X-ray pulses, enabling detailed study of chiral interactions in molecular systems.

Contribution

It introduces a formalism using irreducible tensors to distinguish magnetic dipole and electric quadrupole contributions in chiral X-ray signals, with applications to molecular excitations.

Findings

Different polarization configurations isolate specific chiral interactions.

Configurations can identify the step within nonlinear pathways where chirality occurs.

Application to S-ibuprofen reveals chiral signals at the Carbon K-edge.

Abstract

Chiral four-wave-mixing signals are calculated using the irreducible tensor formalism. Different polarization and crossing angle configurations allow to single out the magnetic dipole and the electric quadrupole interactions. Other configurations can reveal that the chiral interaction occurs at a given step within the nonlinear interaction pathways contributing to the signal. Applications are made to the study of valence excitations of S-ibuprofen by chiral Stimulated X-ray Raman signals at the Carbon K-edge and by chiral visible 2D Electronic Spectroscopy.teraction pathways contributing to the signal.