Study of Activators and Ion Damaging Effects in Natural Diopside by Means of Micro-Ionoluminescence and Micro-PIXE

Diopside is a mineral belonging to the pyroxene family, in particular it is an inosilicate with a single calcium and magnesium chain, whose chemical formula is CaMgSi2O6 . Natural diopside displays a large variety of luminescence centers: at room temperature main features are a 450 nm band, that can be ascribed to the silicate-based network and an intense band at 585 nm that can be ascribed to Mn2+ ions in M2 (Ca2+) sites. Also Ti3+ and Fe-related impurities have a role as activators of luminescence. The main purpose of the present work is to study the radiation hardness of several of such centers by following the evolution of ionoluminescence upon proton irradiation. Moreover an attempt was made to correlate the trace elements to the centers of luminescence by means of micro-PIXE.