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Abstract: The Rhodamine 6G (R6G) dye sample synthesized by thermal evaporation method is irradiated by 120 MeV Ag+9 ions at different fluences from 1 × 1011 ion/cm2 to 3 × 1012 ion/cm2. These samples are characterized by X-ray diffraction (XRD), ultraviolet–visible (UV–Vis) absorption spectroscopy and photo-conductivity measurements. In XRD, it is observed that amorphous nature of dye films increases with fluence and hence aggregates of dye molecules spread homogeneously on the substrate after irradiation. The absorption spectroscopy and photoconductivity results show maximum absorption and minimum photoresistivity at lowest fluence. The properties of the dye films such as increase in amorphous nature, increase in absorption peak area and marginal increase in photoconductivity are favorable for Dye-sensitize solar cell (DSSC) applications. [Copyright &y& Elsevier]

Abstract: LiF crystals doped with different concentration of Mg from 0 to 2000ppm have been grown by edge defined film fed growth technique. The X-ray diffraction measurement confirms the incorporation of the Mg in the lattice. Thermoluminescence and optical absorption measurements have been made on as-grown and annealed crystals after they were irradiated with a gamma dose of 15 and 1500Gy, respectively. The TL glow peak temperature and intensity increase up to 500ppm in case of the as-grown crystals and up to 1000ppm in the annealed crystals and decrease thereafter. The normalized peak height of the annealed crystals is nearly three times that of the as grown crystals for the particular concentration. Corresponding optical absorption spectra of the crystals exhibit prominent bands at 250 and 310nm. The 310nm band increases with increase in concentration of Mg and also with annealing. The changes in the TL glow curves are correlated with those of the optical absorption bands to conclude that the 310 band is due to the Mg related Z2 center. [Copyright &y& Elsevier]