The Advanced Photon Source
a U.S. Department of Energy Office of Science User Facility

Supported Techniques

Overview of 12BM Experimental Setups:

Supported Techniques

At 12-BM-B we have Spectroscopy experiments that can be combined with SAXS and WAXS experiments.  Including Quick EXAFS in transmission geometry with sub 10 second scanning capabilities to better the efficiency for sub minute in-situ reactions allowing combined EXAFS, SAXS/WAXS experiments to be done.

12BM-B has also implemented Mail-In Operations.

XAS (X-ray Absorption fine structure)

X-ray Absorption Fine Structure (XAFS includes EXAFS and XANES) is a method used to gather information regarding the geometric and electronic structure of the materials under study.  EXAFS (Extended X-ray Absorption Fine Structure) gives information about the interatomic distances, nearest neighbors coordination numbers, as well as the lattice dynamics.  XANES yields information on the valance state, energy bandwidth, and bond angles.

At 12-BM-B the Spectroscopy method can be combined with SAXS and WAXS to study samples under changing environments (in-situ) or in static environments (ex-situ).  The use of SAXS/WAXS capabilities at 12-BM-B can only be used in combination with EXAFS type experiments.

SAXS / WAXS (Small/Wide Angle X-ray Scattering)

Small-Angle X-ray Scattering (SAXS) is a nondestructive method used to characterize structures of solid and fluid constituents in the nanometer (nm) range. The technique utilizes the very low angle elastic scattering of x-rays to probe the inhomogeneities of the electron density on the scale of normally 1 – 100nm, giving structural information of the samples being evaluated. By recording the very small angles of scattering one can extract information regarding the shape and size of the molecular structure of the material being investigated.

Wide-Angle X-ray Scattering (WAXS) allows to go further down the scale to sub-nanometer-sized structures due to the increase in angle between the sample and the detector during measurement. This allows for studies on crystallinity of samples and to determine the chemical/phase composition of thin films, crystallite size, as well as possible film stresses.