Quantitative analysis of diffraction by liquids using a pink-spectrum X-ray source

TL;DR

This paper introduces a novel quantitative diffraction analysis method for liquids using pink-spectrum X-ray sources, correcting for beam effects and estimating densities through optimization, demonstrated on tin data.

Contribution

A new approach for structure-factor analysis and density measurement of liquids using pink-spectrum X-ray diffraction with correction and optimization techniques.

Findings

Method accurately estimates densities of liquids from diffraction data.

Demonstrated on simulated and experimental tin data with favorable results.

Applicable to shock compressed liquids at high pressures.

Abstract

We describes a new approach for performing quantitative structure-factor analysis and density measurements of liquids using x-ray diffraction with a pink-spectrum x-ray source. The methodology corrects for the pink beam effect by performing a Taylor series expansion of the diffraction signal. The mean density, background scale factor, peak x-ray energy about which the expansion is performed, and the cutoff radius for density measurement are estimated using the derivative-free optimization scheme. The formalism is demonstrated for a simulated radial distribution function for tin. Finally, the proposed methodology is applied to experimental data on shock compressed tin recorded at the Dynamic Compression Sector at the Advanced Photon Source, with derived densities comparing favorably to other experimental results and the equations of state of tin.