Nanoscale Critical Phenomena in a Complex Fluid Studied by X-Ray Photon Correlation Spectroscopy

Autor: Piotr Maj, Robert Szczygiel, J. Lal, Subramanian K. R. S. Sankaranarayanan, Mark Antonio, Qingteng Zhang, Troy D. Loeffler, Lynda Soderholm, Dina Sheyfer, Eric M. Dufresne, Suresh Narayanan, Alec Sandy, G. B. Stephenson
Rok vydání: 2020
Předmět:
Zdroj: Physical Review Letters. 125
ISSN: 1079-7114
0031-9007
Popis: The advent of high-speed x-ray photon correlation spectroscopy now allows the study of critical phenomena in fluids to much smaller length scales and over a wider range of temperatures than is possible with dynamic light scattering. We present an x-ray photon correlation spectroscopy study of critical fluctuation dynamics in a complex fluid typical of those used in liquid-liquid extraction (LLE) of ions, dodecane-DMDBTDMA with extracted aqueous $\mathrm{Ce}({\mathrm{NO}}_{3}{)}_{3}$. We observe good agreement with both static and dynamic scaling without the need for significant noncritical background corrections. Critical exponents agree with 3D Ising values, and the fluctuation dynamics are described by simple exponential relaxation. The form of the dynamic master curve deviates somewhat from the Kawasaki result, with a more abrupt transition between the critical and noncritical asymptotic behavior. The concepts of critical phenomena thus provide a quantitative framework for understanding the structure and dynamics of LLE systems and a path forward to new LLE processes.
Databáze: OpenAIRE