Investigation of the local structural changes in GeSe2 glass under ultrahigh pressure

Experimental data regarding the relationship between the density and local structural changes in the simple network forming glass under ultrahigh pressures has long been desired. Such an information is essential for understanding the further densification mechanism of network structures after the primary low to high density amorphous-amorphous transformation which is generally associated with a tetrahedral to octahedral coordination crossover. We propose to investigate the local structural changes in a particular model system: GeSe2 glass, under ultrahigh pressures using the double edge EXAFS refinements. We aim to obtain reliable quantitative data that is necessary to further understanding of the behavior of similar simple network forming glasses under ultra-high pressures.The proposed research will have strong interdisciplinary implications including the studies of density and local structural changes in the silicate melts under extreme pressure conditions of the deep Earth.