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Abstract: Modifications of the C70 molecule (fullerene) under swift heavy ion irradiation are investigated. C70 thin films were irradiated with 120MeV Au ions at fluences from 1×1012 to 3×1013 ions/cm2. The energetic ion impacts lead to the destruction of the C70 molecule. To investigate the stability of C70 fullerene, the damage cross-section and radius of the damaged cylindrical zones are evaluated by fitting the evanescence of C70 vibration modes recorded by Raman spectroscopy. Conductivity measurements together with Raman and optical absorption studies revealed that an irradiation fluence of 3×1013 ions/cm2 results in complete amorphization of the carbon structure of the fullerene molecules. [Copyright &y& Elsevier]

Abstract: Thermally evaporated ZnO thin films have been irradiated with 100MeV Au8+ ions at different fluence from 5×1011 ions/cm2 to 5×1013 ions/cm2. The optical and structural properties of the irradiated and pristine films were studied using Fourier transform infrared spectroscopy (FTIR), UV–visible absorption spectroscopy, photoluminescence (PL), atomic force microscopy (AFM) and XRD. FTIR results showed that for low fluence, the transmittance of the film decreased and increased again at higher fluence but Zn–O bond remains unaffected by irradiation. As revealed from the absorption spectra, absorption edge is not changed by the irradiation but the optical absorption is increased. The AFM study of the films implied that roughness decreased at low fluence values up to 5×1012 ions/cm2 and at higher fluences the roughness increased. [Copyright &y& Elsevier]