Solvatochromic and Preferential Solvation Studies on Schiff Base 1,4-Bis(((2-Methylthio)Phenylimino)Methyl) Benzene in Binary Liquid Mixtures

Abstract

The solvatochromic behavior of the 1,4-bis(((2-methylthio) phenylimino)methyl) benzene [BMTPMB] in single solvents and binary mixtures were investigated. Fluorescence spectra show the dual emission due to twisted intramolecular charge transfer (TICT) state. The preferential solvation parameters: local mole fraction, X (2) (L) , solvation index δ(s2), exchange constant K(12) were calculated for the binary mixtures, ACN+MEOH, DMSO+CCl(4) and CCl(4)+1,2 DCE. The dipole moment ratios between ground and excited states were deduced using the solvatochromic shifts of absorption and fluorescence spectra as a function of dielectric constant (ε), refractive index (n) and it was found to be 1.25.

Effect of solvents on photophysical properties and quenching of 2‐{[3‐(1H‐benzimidazole‐2‐yl) phenyl] carbonoimidoyl}phenol

“…The dipole moment in the excited state of the fluorescent molecule also determines the energy tunability range of emission as a function of the polarity of the medium. Solvatochromic studies on Schiff base molecules have shown alteration in photophysical properties such as electronic structure, dipole moments of ground and excited states, and intra and intermolecular interactions in solutions .…”

8(E)-4-[{2-(2,4-dinitrophenyl)hydrazono}benzene-1,3-diol] as a solvatochromic Schiff base and chromogenic signaling of water content by its deprotonated form in acetonitrile

“…1 Solvent effects are related to the nature and the extent of the solute-solvent interactions developed in the solvation shell of the solutes. [2][3][4] The solvent effect can be determined by solvent polarity scale or solvatochromic parameters. 5 The solvent dependent spectral shis can arise from either non-specic (dielectric enrichment) or specic (e.g.…”

Influence of Solvent Polarity on Preferential Solvation of Molecular Recognition Probes in Solvent Mixtures

“…Many theoretical models have been developed to account for solvation phenomena: continuum models where the solvent is considered as a continuous and structureless medium that surrounds the solutes; supramolecular models that consider the solvent molecules around a solute in the same way as the solute itself; and semicontinuum models that consider the solute molecule along with the first solvation shell surrounded by a continuum solvent. − However, it is still difficult to make reliable quantitative predictions of solvent effects on chemical processes, and the description of processes in solvent mixtures is even more complicated, due to the occurrence of preferential solvation. Many techniques have been used to investigate preferential solvation experimentally: UV–vis absorption, − fluorescence, , NMR, − IR absorption, − calorimetry, − circular dichroism, and mass spectrometry . Most of these techniques involve the use of a molecular probe, which has a property that is sensitive to the solvent environment .…”