NIST and Argonne researchers develop new USAXS-XPCS tool at APS

J. Appl. Cryst. (2011). 44, 200-212 (doi.org/10.1107/S0021889810053446)

Correlation coefficient map quantitatively describes how 1D USAXS–XPCS scans from an advanced dental composite sample change during slow cooling from an annealing temperature of 388 K.

Taking advantage of 2D-collimated Bonse-Hart-type crystal optics, NIST and Argonne researchers have developed a new ultra-small-angle X-ray scattering (USAXS)-based X-ray photon correlation spectroscopy (XPCS) measurement technique at the Advanced Photon Source. This technique probes low-frequency equilibrium and nonequilibrium dynamics in optically opaque materials containing prominent features that scatter in a q range between those of dynamical light scattering and conventional XPCS. To date, USAXS-XPCS has been successfully applied to study colloidal suspensions and incipient structural changes in advanced dental composites.