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Femtosecond time resolution in x-ray diffraction experiments.

R Neutze·J Hajdu
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Abstract

This paper presents the theoretical background for a synthesis of femtosecond spectroscopy and x-ray diffraction. When a diffraction quality crystal with 0.1-0.3 mm overall dimensions is photoactivated by a femtosecond laser pulse (physical length = 0.3 microm), the evolution of molecules at separated points in the crystal will not be simultaneous because a finite time is required for the laser pulse to propagate through the body of the crystal. Utilizing this lack of global crystal synchronization, topographic x-ray diffraction may enable femtosecond temporal resolution to be achieved from reflection profiles in the diffraction pattern with x-ray exposures of picosecond or longer duration. Such x-ray pulses are currently available, and could be used to study femtosecond reaction dynamics at atomic resolution on crystals of both small- and macromolecules. A general treatment of excitation and diffraction geometries in relation to spatial and temporal resolution is presented.

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R Neutze, J Hajdu. 1997-05-27. Femtosecond time resolution in x-ray diffraction experiments.. https://doi.org/10.1073/pnas.94.11.5651

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