Избирательная сольватация красителя 4-DASPI в бинарном растворителе вода-этиленгликоль

Solvatochromic shifts of the absorption spectra maxima of the dye 4-DASPI (4- [4- (dimethylamino) styryl] -1-methylpyridinium iodide) in a binary solvent water-ethyleneglycol in the concentration range 0-100% were experimentally investigated. The dependence of the solvatochromic shift on the macroscopic dielectric constant of the solution and the concentration of ethyleneglycol was determined. The Onsager-Liptay model was used for the theoretical interpretation of the experimental data. It made it possible to estimate the effective dielectric constant in the microscopic area that contacts with dye chromophore taking into account the measured solvatochromic shifts. It was found that the value of the dielectric constant in the solvation shell of this dye differs significantly from the macroscopic value. The solvation shell is significantly enriched by ethyleneglycol (preferential solvation) over the components’ concentration range. The enrichment reaches its maximum approximately in the middle of this range. The composition of the dye solvation shell at different concentration is discussed.

Ground and Excited State Dipole Moment of 2,5-Dihydroxybenzoic Acid from Solvatochromic Shifts

In present work we explore the role of solvents on the 2, 5-dihydroxybenzoic acid by using fluorescence techniques. It was found that DHBA shows spectral behaviour depending on polarity of solvents. DHBA shows generally three components at 405-415nm, 430-450nm, and 450-470nm. The effects of zwitterion as well as the interplay ionic species are involved to explain the observed results

Ground and Excited State Dipole Moment of 2,5-Dihydroxybenzoic Acid from Solvatochromic Shifts

In present work we explore the role of solvents on the 2, 5-dihydroxybenzoic acid by using fluorescence techniques. It was found that DHBA shows spectral behaviour depending on polarity of solvents. DHBA shows generally three components at 405-415nm, 430-450nm, and 450-470nm. The effects of zwitterion as well as the interplay ionic species are involved to explain the observed results.

The Bethe–Salpeter formalism with polarisable continuum embedding: reconciling linear-response and state-specific features

The Bethe–Salpeter formalism combined with polarizable models of the environment reconciles linear-response and state-specific contributions to solvatochromic shifts.