Two-Dimensional Stimulated Resonance Raman Spectroscopy of Molecules with Broadband X-ray Pulses

TL;DR

This paper derives expressions for 2D Stimulated X-ray Raman Spectroscopy signals using attosecond pulses and demonstrates their application to trans-N-methyl acetamide, revealing electronic overlaps through crosspeaks.

Contribution

It introduces theoretical expressions for 2D-SXRS signals with broadband x-ray pulses and applies them to a molecular system, highlighting the detection of electronic overlaps.

Findings

Crosspeaks reveal electronic Franck-Condon overlaps.

Signals calculated for trans-N-methyl acetamide.

Broadband pulses enable detailed electronic structure insights.

Abstract

Expressions for the two-dimensional Stimulated x-ray Raman Spectroscopy (2D-SXRS) signal obtained using attosecond x-ray pulses are derived. The 1D- and 2D-SXRS signals are calculated for trans-N-methyl acetamide (NMA) with broad bandwidth (FWHM ~14.2eV, 181 as) pulses tuned to the oxygen and nitrogen K-edges. Crosspeaks in 2D signals reveal electronic Franck-Condon overlaps between valence orbitals and relaxed orbitals in the presence of the core hole.