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Title: Imaging electron-density fluctuations by multidimensional X-ray photon-coincidence diffraction

The ultrafast spontaneous electron-density fluctuation dynamics in molecules is studied theoretically by off-resonant multiple X-ray diffraction events. The time- and wavevector-resolved photon-coincidence signals give an image of electron-density fluctuations expressed through the four-point correlation function of the charge density in momentum space. A Fourier transform of the signal provides a real-space image of the multipoint charge-density correlation functions, which reveal snapshots of the evolving electron density in between the diffraction events. The proposed technique is illustrated by ab initio simulations of the momentum- and real-space inelastic scattering signals from a linear cyanotetracetylene molecule.

Authors:
; ; ;
Award ID(s):
1663822
Publication Date:
NSF-PAR ID:
10082159
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
116
Issue:
2
Page Range or eLocation-ID:
p. 395-400
ISSN:
0027-8424
Publisher:
Proceedings of the National Academy of Sciences
Sponsoring Org:
National Science Foundation
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