Solvatochromism involving Rhodamine-6G

The solvatochromic shift of a molecular fluorophore is the change in the absorption and emission spectra and is caused by the dipole interactions that take place between it and the solvent. Rhodamine-6G (R6G) was used because it is a good example of a molecular fluorophore that exhibits this phenomena. In most organic solutions, Rhodamine-6G becomes aqueous and acts similar to a salt. forming an organic ionic molecule and an ionized Chlorine atom. This ionic molecule is affected by the polarity of the solution into which it is dissolved.
To better understand the solvatochromic shifting of Rhodamine-6G, the dipole interactions must be further researched. This can be done by measuring R6G spectra of different solutions and calculating the Stokes Shift. The Stokes Shift is the difference between the peak absorption wavelength and peak emission wavelength. These peaks allow for the calculation of the dipole moments in each solution. There are several methods to determine dipole moments and change in dipole moments. The most commonly used methods were developed by Lippert-Malaga,
Bakhs.h..ie. v, Catalan, Kamlet-Taft, Reichardt, and Bilot-Kawski.
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Abstract/Description: The solvatochromic shift of a molecular fluorophore is the change in the absorption and emission spectra and is caused by the dipole interactions that take place between it and the solvent. Rhodamine-6G (R6G) was used because it is a good example of a molecular fluorophore that exhibits this phenomena. In most organic solutions, Rhodamine-6G becomes aqueous and acts similar to a salt. forming an organic ionic molecule and an ionized Chlorine atom. This ionic molecule is affected by the polarity of the solution into which it is dissolved. To better understand the solvatochromic shifting of Rhodamine-6G, the dipole interactions must be further researched. This can be done by measuring R6G spectra of different solutions and calculating the Stokes Shift. The Stokes Shift is the difference between the peak absorption wavelength and peak emission wavelength. These peaks allow for the calculation of the dipole moments in each solution. There are several methods to determine dipole moments and change in dipole moments. The most commonly used methods were developed by Lippert-Malaga, Bakhs.h..ie. v, Catalan, Kamlet-Taft, Reichardt, and Bilot-Kawski.
Subject(s): Organic fluorophones
Undergraduate Research