Chemically induced glass-glass transition in a CeCoAl metallic glass at high pressure

The intense x-rays available at EBS-ESRF are known to be able to trigger undesired effects, like structural and chemical modifications in radiation sensitive materials. This apparent obstacle can also lead to the discovery of new, surprising, physical phenomena. Recently, we observed a structural expansion of a Ce65Al10Co25 metallic glass (MG) during high pressure compression which appears related to an x-ray induced or photocatalytic reactions between the MG and the pressure transmitting medium. We propose, here, to couple high pressure x-ray diffraction and x-ray absorption spectroscopy to study the structural evolution occurring in this glass under different chemical environments and irradiation conditions to trigger and control the transition and quantify the corresponding structural changes. A successful experiment will lead to the determination of the microscopic mechanisms behind the transition, and provide insights on the anomalous equation of state of the newly formed MG.