In the Laboratory
Visible Absorption Spectroscopy and Structure of Cyanine Dimers in Aqueous Solution
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An Experiment for Physical Chemistry Miin-Liang Horng and Edward L. Quitevis* Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061; *
[email protected] The visible absorption spectra of conjugated cyanine dyes have long been used in undergraduate physical chemistry laboratories to demonstrate the relationship between electronic energy level spacings and the wavelengths of visible absorption bands (1). This relationship is quantitatively interpreted using the free-electron model. In these experiments, the absorption spectra of dilute (
