Double flourescence detection of XANES and EXAFS signals from dilute species in competing fluorescent matrices

Abstract

A double flourescence scheme for detecting XANES (X-ray absorption near-edge structure) and EXAFS (extended X-ray absorption fine structure) signals from a dilute species in a bulk competing flourescent matrix is reported. The new scheme has been demonstrated for the case of a Western Australian mineral specimen containing ∼ 900 ppm of Au, and is particularly suitable for chemical and structural investigation of low concentration species in a matrix of similar, but slightly lower atomic number(s). The technique has the advantage of largely eliminating unwanted background arising from the bulk matrix.