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An analysis program for near-edge X-ray absorption fine-structure (NEXAFS) spectra has been developed and implemented at the soft X-ray beamline of the Australian Synchrotron. The program allows for instant viewing of corrected data channels including normalizations to a standard, double normalizations when the standard itself has an undesired spectral response, and background subtraction. The program performs simple compositional analysis and peak fitting and includes rapid common calculations such as the average tilt angle of molecules with respect to the surface, and the determination of the complex index of refraction, which previously required intensive manual analysis. These functionalities make common manipulations carried out with NEXAFS data quick and straightforward as spectra are collected, greatly increasing the efficiency and overall throughput of NEXAFS experiments.

Tc L3-edge XANES spectra have been collected on powder samples of SrTcO3 (octahedral Tc(4+)) and NH4TcO4 (tetrahedral Tc(7+)) immobilized in an epoxy resin. Features in the Tc L3-edge XANES spectra are compared with the pre-edge feature of the Tc K-edge as well as other 4d transition metal L3-edges. Evidence of crystal field splitting is obvious in the Tc L3-edge, which is sensitive to the coordination number and oxidation state of the Tc cation. The Tc L3 absorption edge energy difference between SrTcO3 (Tc(4+)) and NH4TcO4 (Tc(7+)) shows that the energy shift at the Tc L3-edge is an effective tool for studying changes in the oxidation states of technetium compounds. The Tc L3-edge spectra are compared with those obtained from Mo and Ru oxide standards with various oxidation states and coordination environments. Most importantly, fitting the Tc L3-edge to component peaks can provide direct evidence of crystal field splitting that cannot be obtained from the Tc K-edge.

YB(66)(400) crystals present a new advance in monochromator crystals suitable for use at energies below 2 keV. In this paper a comparison of their performance with that provided by the more usual beryl and quartz crystals, which cover the same energy range, is presented. In general, the YB(66) crystals are much superior; however, they do exhibit a pair of large 'crystal glitch'-type features in the 1380-1440 eV region. These fall in the Mg K-EXAFS region and so can present a serious problem in studies of this edge for a wide range of materials. An important class of materials so afflicted are magnesium-substituted aluminophosphate molecular sieves (zeolites), which are used in many applications, in particular as solid acid catalysts for conversion of methanol to hydrocarbon.