Solvent Effects upon Fluorescence Spectra and the Dipolemoments of Excited Molecules

Abstract

A general formula for the difference of solvent shifts of fluorescence and absorption spectra in the approximation of long range dipolar interaction was derived using Ooshika’s theory of light absorption in solution. Measurements of fluorescence and absorption spectra of some naphthalene derivatives in various organic solvents were undertaken, and the data were analysed by the theoretical formula. The formula reproduces the experimental data satisfactorily, and from this fact it was concluded that the most predominant factor which determines the difference of solvent shifts of fluorescence and absorption spectra of these molecules is the interaction energy between solute and solvent molecules due to orientation polarization. The incremental values of dipolemoments in the excited state were estimated, and those for α-, β-naphthols and β-naphthyl methyl ether were interpreted as due to the increase of electron migration from the substituent in the excited state.

The protein fluorescence and structural toolkit: Database and programs for the analysis of protein fluorescence and structural data

“…The tryptophan residues, which belong to various classes, have different spectral and structural properties and, as a result, the different combinations of universal (dipole-dipole relaxation [16][17][18][19][20][21][22][23] and specific (exciplex formation 24-28 ) interactions could occur in the excited state of tryptophan fluorophores.…”

Effects of environment on the photophysical characteristics of mesotetrakis methylpyridiniumyl porphyrin (TMPyP)

“…The Stokes shift, calculated according to st = abs − em , where abs is the absorption peak position with lowest frequency and em is the position of the fluorescence peak with highest frequency, does not exceed 200 cm −1 (≈8 nm) and differs in different organic solvents by less than 10 cm −1 , as shown in Table 3. According to Lippert-Mataga's theory [30,31], the Stokes shift associated to the solvent is:…”

Synthesis and Photophysical Characterizations of Thermal -Stable Naphthalene Benzimidazoles

“…The parameters ε and n are the solvent dielectric constant and refraction index, respectively, which are grouped in the term Δf, known as orientation polarizability. A plot of ΔU versus Δ f gives Δμ [33][34][35].…”