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arXiv:2401.00259 · The Journal of Physical Chemistry Letters

Ultrafast X-ray Diffraction Probe of Coherent Spin-State Dynamics in Molecules

Xiaoyu Mi, Ming Zhang, Zheng Li

Published Jan 11, 2024• 2 citations
arXivHTMLPDF

Abstract

We propose an approach to probe coherent spin-state dynamics of molecules using circularly polarized hard X-ray pulses. For the dynamically aligned nitric oxide molecules in a coherent superposition spin-orbit coupled electronic state that can be prepared through stimulated Raman scattering, we demonstrate the capability of ultrafast X-ray diffraction to not only reveal the quantum beating of the coherent spin-state wave packet but also image the spatial spin density of the molecule. With a circularly polarized ultrafast X-ray diffraction signal, we show that the electronic density matrix can be retrieved. The spatiotemporal resolving power of ultrafast X-ray diffraction paves the way for tracking transient spatial wave function in molecular dynamics involving the spin degree of freedom.

DOI
10.1021/acs.jpclett.3c02892

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