Modulation of intramolecular charge transfer reaction of ethyl ester of N,N-Dimethylaminonaphthyl- (acrylic)-acid (EDMANA) in anionic sodium dodecyl sulfate (SDS), cationic cetyltrimethylammonium bromide (CTAB) and non-ionic p-tert-octylphenoxy polyoxyethanol (Triton-X 100, TX-100) micelles has been addressed using steady state and time resolved spectroscopy. The interaction of the CT probe EDMANA with micelles and its location inside the micelles have been investigated by the study of fluorescence spectral band position of EDMANA in micelle, the effective polarity of micelle-water interface and cetyl pyridinium chloride induced fluorescence quenching measurement. The effects of urea on the properties of the micelles such as Critical Micelle Concentration and the interaction between EDMANA and micelles have been explored using EDMANA as emission probe. © 2011 Springer Science+Business Media, LLC.

NIKHIL GUCHHAIT

Chemistry

A SAMANTA

B K PAUL

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Journal of Fluorescence

The photophysical behavior of 2-methoxy-4-(N,N-dimethylamino)benzaldehyde (2-MDMABA) has been investigated by steady state absorption and emission spectroscopy, time resolved emission spectroscopy and quantum chemical calculations. The molecule 2-MDMABA having a weak acceptor aldehyde group shows strong local emission in all solvents and a weak solvent polarity dependent red shifted emission in polar aprotic solvents for the charge transfer (CT) state which follows well the Lippert-Mataga equation. Instead of usual protonation at the donor site with inhibition of CT process, protonation at the acceptor aldehyde site enhances acceptor properties and hence increases excited state charge transfer reaction. The ground state structural calculation at Density Functional Theory (DFT) level with B3LYP functional and 6-31++ G** basis set and potential energy surfaces (PESs) following twisted intramolecular charge transfer model by using DFT method in the gas phase and in acetonitrile solvent have been performed for the neutral and cation to correlate with experimental findings. © 2010 Elsevier B.V. All rights reserved.

Journal of Photochemistry and Photobiology A: Chemistry

Evidence of acid mediated enhancement of photoinduced charge transfer reaction in 2-methoxy-4-(N,N-dimethylamino)benzaldehyde: Spectroscopic and quantum chemical study

The present work describes the synthesis and photophysical studies of two fluorescent dansylamide derivatives, in which the amine group is acylated by a long hydrophobic chain (a part of a biologically relevant palmitic acid) and by a short hydrophobic tail (a part of acetic acid). The long chain tethered dansyl analogue is successfully utilized in estimating critical micellar concentration (CMC) of bile salts (NaDC, NaC) as well as anionic and cationic surfactants (SDS, CTAB) with the help of enhanced fluorescence intensity facilitated by better solubilization of the molecule in microheterogeneous media. The long chain tethered dansylamide derivative shows significant fluorescence solvatochromism with a red shift (ca. 4000 cm-1) from hexane to water. In contrast, the solvatochromism exhibited by the parent/short acyl chain analogue is much less (ca. 2230 cm-1 from hexane to water) and the fluorescence is not sensitive to micellization. Interestingly, the long chain tethered fluorescent probe shows high sensitivity towards premicellar aggregation of sodium deoxycholate (NaDC) bile salt, through a clear blue shift of emission maxima and concomitant enhancement of fluorescent intensity. Such an observation of fluorescence sensing of premicellar aggregation is unusual. © the Owner Societies 2015.

Physical Chemistry Chemical Physics

Fluorescence of N-acylated dansylamide with a long hydrophobic tail: Sensitive response to premicellar aggregation of sodium deoxycholate

In this work, we have studied the twisted intramolecular charge transfer process in ethyl ester of N,N′-Dimethylaminonaphthyl-(acrylic)-acid (EDMANA) using absorption and emission spectroscopy. Single conformer of EDMANA present in the ground state gives rise to local and charge transfer emission in different solvents. Solvatochromic effect on the Stokes shifted emission band clearly indicates the charge transfer character of the emitting singlet excited state. Considering twisted intramolecular charge transfer model, the ground and excited state properties of EDMANA have been evaluated along the donor and acceptor twisting coordinates separately using density functional theory (DFT) and time dependent density functional theory (TDDFT), respectively, with B3LYP functional and 6-31G basis set. The effect of solvent on the spectral properties has been explored theoretically at the same level with time dependent density functional theory-polarized continuum model (TDDFT-PCM) and the theoretical results support the solvent polarity dependent Stokes shifted emission of EDMANA molecule. © 2007 Elsevier B.V. All rights reserved.

Chemical Physics

Spectroscopic study of excited state intramolecular charge transfer in ethyl ester of N,Nâ€²-Dimethylaminonaphthyl-(acrylic)-acid

The Journal of Physical Chemistry A

Effects of Liquid Crystal Environment on the Spectroscopic and Photophysical Properties of Well-Known Reacting Systems 2,3-Dimethylindole (DMI) and 9-Cyanoanthracene (9CNA)

Journal	Data powered by TypesetJournal of Fluorescence
Publisher	Data powered by TypesetSPRINGER/PLENUM PUBLISHERS
ISSN	1053-0509
Open Access	No