Time-resolved study of the photochemical reaction of 4-dimethylaminobenzonitrile with carbon tetrachloride

C. Ma, Wai Ming Kwok, P. Matousek, W. Parker, D. Phillips, M. Towrie, P. Toner

Research output: Journal article publicationJournal articleAcademic researchpeer-review

12 Citations (Scopus)

Abstract

The mechanism of 4-dimethylaminobenzonitrile (DMABN) fluorescence quenching by carbon tetrachloride was studied using time-resolved fluorescence, absorption and Raman techniques. Picosecond and nanosecond time-resolved Raman spectra of DMABN and DMABN-d6were obtained in resonance with different electronic states to identify intermediates, their structure and time-dependent dynamic changes. The quenching is attributed to intermolecular electron transfer between B-state DMABN and carbon tetrachloride with a time constant of ∼500 fs leading to the formation of the DMABN radical cation as the initial intermediate followed by a ∼13 ps process yielding a DMABN-Cl adduct as product with a lifetime longer than 50 ns. It is likely that the chlorine atom is located at the amino para-ring position of the highly reactive DMABN radical cation. It is suggested that this reaction mechanism is general for other donor-aromatic-acceptor type DMABN derivatives.
Original languageEnglish
Pages (from-to)115-123
Number of pages9
JournalJournal of Raman Spectroscopy
Volume32
Issue number2
DOIs
Publication statusPublished - 1 Jan 2001
Externally publishedYes

ASJC Scopus subject areas

  • Materials Science(all)
  • Spectroscopy

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