Elfs: Energy Loss Fine Structure Analysis in Materials

Abstract

ELFS (energy loss fine structure), similar to XAFS (x-ray absorption fine structure) provides short-range order atomic structural information of crystalline and amorphous materials. Although known quite sometime, ELFS spectroscopy only until recently has gained importance, mainly due new developments in spectrometer and TEM designs, spectra acquisition and interpretation techniques. This paper focuses on some new developments in the acquisition, interpretation, and the use of the extended regime of the ELFS spectroscopy.Although fine structure spectroscopy in EELS and its similarity to XAFS were recognized sometime ago, ELFS has only seen limited use mainly because of insufficient spectral statistics, various systematic errors and drifts, and the absence of sophisticated software that faithfully uses the XAFS software and incorporates the latest advances in modeling theory. We have systematically improved the data acquisition technique and developed ELFS data analysis procedure which utilizes the sophisticated UWXAFS data analysis software package8 after correction of the differences between ELFS and XAFS data.