A physiochemical study of excited state intramolecular proton transfer process: Luminescent chemosensor by spectroscopic investigation supported by ab initio calculations

  • Jayabharathi J
  • Thanikachalam V
  • Jayamoorthy K
 et al. 
  • 5

    Readers

    Mendeley users who have this article in their library.
  • 40

    Citations

    Citations of this article.

Abstract

A group of novel Schiff base derivatives were synthesized and characterized by NMR spectra, X-ray, mass and CHN analysis. An excited state intramolecular proton transfer (ESIPT) process in hydroxy Schiff base (SB4) has been studied using emission spectroscopy and it was detected that the two distinct ground state isomers of I and II are responsible for the emission. The comparison of the emission wavelength in hydrocarbon solvent strongly supports that trans enol form predominates over the cis enol form for Schiff base (SB4). With increasing base concentration of the solutions of hydroxy substituted Schiff bases (SB4 and SB5), two isobestic points are found which confirm the equilibrium among the trans enol form, anion and the cis enol form. The fluorescence of (SB4) quenched markedly with the gradual addition of Cu2+but the fluorescence properties of (SB5) was influenced by other metal ions. Therefore Schiff base (SB5) can be used as a new fluorescence sensor to detect the quantity of Cu2+ion in any sample solution depending on the relative intensity change. DFT calculations on energy, dipole moment, charge distribution of the rotamers in the ground and excited states of the Schiff base derivatives were performed and discussed. PES calculation indicates that the energy barrier for the interconversion of two rotamers is too high in the excited state than the ground state. © 2010 Elsevier B.V. All rights reserved.

Author-supplied keywords

  • Ab initio calculations
  • Electrical properties
  • Nuclear magnetic resonance (NMR)
  • Photoluminescence spectroscopy

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Authors

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free