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Development of Ultrasmall-Angle X-ray Scattering - X-ray Photon Correlation Spectroscopy



Fan Zhang, Andrew J. Allen, Lyle E. Levine, Jan Ilavsky, Gabrielle G. Long, Anthony M. Santana


In this paper, we present the development of ultrasmall-angle X-ray scattering - X-ray photon correlation spectroscopy (USAXS-XPCS). This technique takes advantage of Bonse-Hart crystal optics and is capable of probing the slow equilibrium and nonequilibrium dynamics of optically opaque materials with prominent scattering features in a scattering vector range between those of dynamical light scattering and conventional XPCS. Instrumental parameters for optimal coherent-scattering operation are described. We offer two examples to illustrate the applicability and capability of USAXS-XPCS. The first example concerns the equilibrium dynamics of colloidal dispersions of polystyrene microspheres in glycerol at 10 %, 15 % , and 20 % volume concentrations. The temporal intensity autocorrelation analysis shows that the relaxation time of the microspheres exhibits a monotonic decay as the scattering vector increases. The second example concerns the nonequilibrium dynamics of a polymer nanocomposite, for which it is demonstrated that USAXS-XPCS measurements can reveal incipient dynamical changes not observable by other techniques.
Journal of Applied Crystallography


X-ray photon correlation spectroscopy, ultra-small-angle X-ray scattering, equilibrium dynamics, nonequilibrium dynamics, coherent X-ray scattering


Zhang, F. , Allen, A. , Levine, L. , Ilavsky, J. , Long, G. and Santana, A. (2011), Development of Ultrasmall-Angle X-ray Scattering - X-ray Photon Correlation Spectroscopy, Journal of Applied Crystallography, [online], (Accessed April 23, 2024)
Created January 31, 2011, Updated October 12, 2021