Structural Modifications in Vitreous SiO<sub>2</sub> Induced by N and Ar Ion Irradiation: Competing Roles of Nuclear and Electronic Energy Losses

This study investigated structural modifications in vitreous silica (SiO2) induced by low-energy ion irradiation using 75 keV N5+ and 165 keV Ar11+ ions. The primary goal was to clarify the competing roles of nuclear and electronic energy losses in these changes. Fourier transform infrared spectroscopy revealed a decrease in the 1078 cm-1 TO3 band and the appearance of a 1044 cm-1 peak, indicating bond angle distortion and densification. Comparative analysis, supported by the unified thermal spike model, demonstrates that nuclear energy loss is the dominant mechanism driving structural transformations under these irradiation conditions, with electronic energy loss having a limited impact.