Rotational Diffusion of Coumarin Dye Molecules in polar and non-polar solvents
نویسنده
چکیده
Absract: Rotational dynamics of two structurally similar coumarins; coumarin 7 and coumarin 30 has been studied using a steady state fluorescence depolarization technique and time correlated single photon counting method as a function of temperature in ethanol and n-decane solvents. Experimentally measured reorientation times of these coumarins are identical in a given solvents at a particular temperature. The present study has been undertaken to examine the role of friction experienced by the polar solutes in a polar solvents. Molecular shape and size are similar but the friction experienced by these probes in ethanol and n-decanol solvents were varies. However, it was observed that coumarin 30, coumarin 7 rotates faster in alcohol than alkane and the observed results are discussed in the last section.
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