Fourier-Filtration Of Xanes As A Source Of Quantitative Information Of Distances And Coordination Numbers In Amorphous Compounds. Application To Diopside Glass

The local atomic structure of amorphous compounds is extensively studied by their X-ray absorption near edge structure (XANES), especially when EXAFS-oscillations cannot be observed. However, the analysis of the unknown structures provides only indirect and qualitative information since it is usually performed comparing the XANES features of the compound studied with heat of the reference ones. One of the main problems is to choose the appropriate references and to reveal for them the characteristic features, which reflect the type of the atoms local environment. By this approach, the local structure of glasses, clays, gels etc consist of low Z elements, studied using as references the Al-,Si-XANES in crystalline minerals, with known site symmetry and site occupancy.