Journal ArticleDOI

# Multidimensional X-Ray Spectroscopy of Valence and Core Excitations in Cysteine

, Yu Zhang1

TL;DR: The coupling between valence- and core-excited states can be visualized in three-dimensional plots, revealing the origin of the polarizability that controls the simpler pump-probe SXRS signals.

AbstractSeveral nonlinear spectroscopy experiments which employ broadband x-ray pulses to probe the coupling between localized core and delocalized valence excitation are simulated for the amino acid cysteine at the K-edges of oxygen and nitrogen and the K and L-edges of sulfur. We focus on two dimensional (2D) and 3D signals generated by two- and three-pulse stimulated x-ray Raman spectroscopy (SXRS) with frequency-dispersed probe. We show how the four-pulse x-ray signals $\boldsymbol{k}_\mathrm{I}=-\boldsymbol{k}_1+\boldsymbol{k}_2+\boldsymbol{k}_3$ and $\boldsymbol{k}_\mathrm{II}=\boldsymbol{k}_1-\boldsymbol{k}_2+\boldsymbol{k}_3$ can give new 3D insight into the SXRS signals. The coupling between valence- and core-excited states can be visualized in three dimensional plots, revealing the origin of the polarizability that controls the simpler pump-probe SXRS signals.

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### Cites background from "Multidimensional X-Ray Spectroscopy..."

• ...Comparing the 2D signals with different middle probe pulses would bring valuable insights on the complicated many-body interaction of localized excitations [63]....

[...]

• ...Calculated multidimensional SXRS signals reveal the coupling between various core and valence excitations localized at different x-ray chromorphores in cysteine (figure adapted with permission from [63]....

[...]

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