Van der Waals Interaction Probed by Solvatochromic Shifts
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The study of molecular systems in the liquid phase is important for understanding a large number of chemical, physical and biological processes. The solvent interaction leads to changes in the molecular solute affecting its spectroscopic, structural and reactive properties. For this reason, the study of solvent effects has been a topic of increased interest1,2. UV-Vis absorption spectrum is very sensitive to solvent effects and it can thus be used judiciously in modeling intermolecular interaction. In this context van der Waals interactions can also be probed in the study of solvatochromic shifts. In particular for the case of nonpolar molecules in nonpolar medium the only remaining term of the dipolar van der Waals interaction is the so-called London dispersion term3. Dispersion is the mutual induced polarisation between the two sub-systems. Liptay4 has shown that dispersion interaction between the chromophore and the solvent contributes to a negative, or red, shift.
KeywordsSolvent Molecule Radial Distribution Function Solvation Shell Dispersion Interaction Single Excitation
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