ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Femtosecond Time-Resolved Raman Spectroscopy Reveals Structural Evidence for meta Effect in Stilbenols

Kayal, Surajit (2018) Femtosecond Time-Resolved Raman Spectroscopy Reveals Structural Evidence for meta Effect in Stilbenols. In: JOURNAL OF PHYSICAL CHEMISTRY A, 122 (19). pp. 4601-4608.

[img] PDF
Jou_Phy_che-A_122-19_4601_2018.pdf - Published Version
Restricted to Registered users only

Download (2MB) | Request a copy
Official URL: https://dx.doi.org/10.1021/acs.jpca.7b12339

Abstract

The met a effect in substituted aromatics plays a crucial role in their excited-state photophysical properties. Meta-substituted hydroxyarenes such as naphthols, stilbenols, and chromophoric constituents of green fluorescent proteins show unusual photoacidity and enhanced fluorescence lifetime and quantum yield when compared to their para-derivatives. Variation in the excited state features of the meta-derivatives when compared to the para-derivatives in stilbenols has been attributed to the enhanced torsional barrier for interconversion between the planar and the twisted perpendicular forms. Herein, we employed femtosecond time-resolved Raman spectroscopy to provide the direct structural evidence for the enhanced torsional barrier in meta-stilbenol. The Raman band profiles of the olefinic C=C stretch related to the torsional motion are found to decay with time constants of similar to 750 and similar to 13 ps in meta-stilbenol and para-stilbenol respectively, unraveling the structural evidence for the observed enhanced photoacidity originating from enhanced rates of excited-state proton transfer. Further, time-resolved fluorescence measurements are performed to elucidate the relaxation pathways of the excited states of the stilbenols.

Item Type: Journal Article
Additional Information: Copy right of this article belong to AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA
Department/Centre: Division of Chemical Sciences > Inorganic & Physical Chemistry
Depositing User: Id for Latest eprints
Date Deposited: 13 Jun 2018 15:26
Last Modified: 06 Sep 2018 11:57
URI: http://eprints.iisc.ac.in/id/eprint/60005

Actions (login required)

View Item View Item