On the basis of the best fitting of optical absorption data, it is suggested that the band gap follows direct optical transitions and its value decreases on adding the Se content to the presently studied system. One of the possible reasons behind this decrease in band gap may be due to the increase in the disorderedness of the

system, which results in an increase in the density of defect states. The value of refractive index increases with the increase in photon energy, whereas the value of extinction coefficient decreases with the increase in photon energy and Se concentration. The calculated values of real and CDK inhibitor imaginary parts of dielectric constants are found to decrease with the increase in Se content for the present system. On the basis of the above reported values of optical parameters, one may decide the suitability of these nanorods for optical devices. Acknowledgements This project was funded by the Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah, under grant no. 81/130/1433. The author therefore acknowledges with thanks DSR technical and financial support. References 1. see more Walsh PJ, Vogel R, Evans E: Conduction and electrical switching in amorphous chalcogenide semiconductor films. J Phys Rev 1969, 178:1274.CrossRef 2. Weirauch DF: Threshold switching and thermal filaments in amorphous

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transition and crystallization behavior in Ga 15 Se 85-x Pb x (0 ≤ x ≤ 6) chalcogenide glasses. Acta Physica Polonica A 2012, 10:12693/A. 5. Al-Agel FA, Al-Arfaj EA, Al-Marzouki FM, Khan SA, Khan ZH, Al-Ghamdi AA: Phase transformation kinetics and optical properties of Ga–Se–Sb phase-change thin films. Mater Sci Semicon Proc 2013,6(13):884.CrossRef 6. Al-Agel FA, Al-Arfaj EA, Al-Marzouki FM, Khan SA, Khan ZH, Al-Ghamdi AA: Glutathione peroxidase Kinetics of phase transformation in nanostructured Ga–Se–Te glasses. J Nanosci Nanotech 2013, 2:1. 7. Khan ZH, Al-Ghamdi A, Al-Agel FA: Crystallization kinetics in as-synthesis high yield of a-Se 100-x Te x nanorods. Mater Chem Phys 2012, 134:260.CrossRef 8. Khan ZH: Glass transition kinetics of a-Se x Te 100-x nanoparticles. Sci Adv Mater 2012, 4:1.CrossRef 9. Labadie L, Kern P, Arezki B, Vigreux-Bercovici C, Pradel A, Broquin J-E: M-lines characterization of selenide and telluride thick films for mid-infrared interferometry. Opt Express 2006, 14:8459.CrossRef 10. Katsumi Abe H, Takebe K, Morinaga J: Preparation and properties of GeGaS glasses for laser hosts. Non-Cryst Solids 1997, 212:143.CrossRef 11. Alegría A, Arruabarrena A, Sanz F: Switching in Al-As-Te glass system. J Non-Cryst Solids 1983, 58:17.CrossRef 12.