QUALITATIVE INTERPRETATION OF ELECTRON ENERGY-LOSS NEAR-EDGE STRUCTURE IN NATURAL ZIRCON

The results of an electron energy-loss spectroscopy (EELS) study of zircon are reported. It is shown that the oxygen K-shell, and the silicon K- and L2,3-shell excitations exhibit near-edge structure significantly different to that observed in other nesosilicates. The spectra have been modelled using multiple-scattering calculations, and these results, combined with results from molecular orbital calculations, have enabled assignment of most of the features in the energy-loss spectra to particular electronic transitions. It is concluded that ELNFS 'fingerprints' are associated not with coordination, but with the symmetry at the central atom site.