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arXiv · 1106.3659

J-aggregates of thiacyanine dye organized in LB films: effect of irradiation of light

Syed Arshad Hussain·D. Dey·S. Chakraborty·D. Bhattacharjee
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Abstract

In the present communication we report the preparation and characterizations of Langmuir and Langmuir-Blodgett films of a thiacyanine dye-dioctadecyl thiacyanine perchlorate (NK) mixed with Octadecyl trimethyl ammonium bromide (OTAB). The relationship between the molar ratio of OTAB and NK and the orientation of molecules at the air-water interface was investigated using surface pressure - area per molecule (π-A) isotherm. UV-Vis absorption and fluorescence spectroscopic investigations reveal that prominent J-aggregation of NK molecule was observed in the LB films lifted at higher surface pressure. This J-aggregation can be controlled by diluting the NK molecules with OTAB. It was observed that the J-aggregates of NK decayed to monomer and H-aggregates when the NK-LB film was exposed to a monochromatic light of wavelength 460 nm (Lambda max of J - aggregates).

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Syed Arshad Hussain, D. Dey, S. Chakraborty, D. Bhattacharjee. 2011-06-18. J-aggregates of thiacyanine dye organized in LB films: effect of irradiation of light. https://doi.org/10.1016/j.jlumin.2011.04.003

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