Temperature dependence of the spetroscopic and structural properties of T1GaS2 and T1InS2 crystals

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2004

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Açıkgöz, Muhammed

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The results of photoluminescence (PL) spectra of TlGaS2 single crystal were reported in the 500-1400 nm wavelength and in the 15-115 K temperature range. Three broad PL bands with an asymmetric Gaussian lineshapes were observed to be centered at 568 nm (A-band), 718 nm (B-band) and 1102 nm (C-band). The shift of the emission band peak energy as well as the change of the half-width of the emission band with temperature and excitation laser intensity were also studied. We analyzed the observed results using the configurational coordinate (CC) model. The powder diffraction patterns of TlInS2 and TlGaS2 crystals were obtained and the diffraction data were indexed using CRYSFIRE computer program packet. TlInS2 has hexagonal system with parameters a = 3.83 and c = 14.88 Ao. TlGaS2 has monoclinic system with parameters a = 9.62, b = 4.01 and c = 7.52 Ao with β= 96.30o. Our diffraction studies at low temperatures did not reveal any phase transition for TlInS2 as reported in the literature. The specific heat capacities of both TlInS2 and TlGaS2 crystals calculated from Differential Scanning Calorimetry (DSC) measurements at low temperatures are reported in the thesis.

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Spectroscopy.

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http://etd.lib.metu.edu.tr/upload/12605222/index.pdf
https://hdl.handle.net/11511/14378

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. Açıkgöz, “Temperature dependence of the spetroscopic and structural properties of T1GaS2 and T1InS2 crystals,” M.S. - Master of Science, Middle East Technical University, 2004.