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arXiv · 1607.01938

Calculation of x-ray scattering patterns from nanocrystals at high x-ray intensity

Malik Muhammad Abdullah·Zoltan Jurek·Sang-Kil Son·Robin Santra
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Abstract

We present a generalized method to describe the x-ray scattering intensity of the Bragg spots in a diffraction pattern from nanocrystals exposed to intense x-ray pulses. Our method involves the subdivision of a crystal into smaller units. In order to calculate the dynamics within every unit we employ a Monte-Carlo (MC)-molecular dynamics (MD)-ab-initio hybrid framework using real space periodic boundary conditions. By combining all the units we simulate the diffraction pattern of a crystal larger than the transverse x-ray beam profile, a situation commonly encountered in femtosecond nanocrystallography experiments with focused x-ray free-electron laser radiation. Radiation damage is not spatially uniform and depends on the fluence associated with each specific region inside the crystal. To investigate the effects of uniform and non-uniform fluence distribution we have used two different spatial beam profiles, gaussian and flattop.

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Malik Muhammad Abdullah, Zoltan Jurek, Sang-Kil Son, Robin Santra. 2016-07-07. Calculation of x-ray scattering patterns from nanocrystals at high x-ray intensity. https://doi.org/10.1063/1.4958887

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