ENVIRONMENTAL AND BIOLOGICAL APPLICATIONS OF EXTENDED X-RAY ABSORPTION FINE STRUCTURE (EXAFS) AND X-RAY ABSORPTION NEAR EDGE STRUCTURE (XANES) SPECTROSCOPIES

Abstract

ABSTRACT XAS (X-ray absorption spectroscopy) has proven to be a powerful technique in several fields including the biological and environmental sciences. It has enabled scientists to analyze samples that could not be analyzed using classical techniques such as XRD (X-ray diffraction). In addition, it allows for the direct determination of elemental oxidation states, where the use of other methods is time consuming, cumbersome, and can lead to false results. XAS experimentation has allowed the direct determination of the local coordination environments in many different samples. This review article briefly explains some of the concepts related to two of the most important techniques of XAS, which are EXAFS (extended X-ray absorption fine structure) and XANES (X-ray absorption near edge structure). An explanation of some of the parameters used to obtain XAS data and data reduction from raw spectroscopic data is discussed. Finally, some applied examples are given that has been obtained though the use of XAS in the biological and the environmental fields.