Two-Dimensional Fluorescence (Excitation/Emission) Spectroscopy as a Probe of Complex Chemical Environments
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- 作者：Neil J. Reilly ; Timothy W. Schmidt ; Scott H. Kable
- 刊名：Journal of Physical Chemistry A
- 出版年：2006
- 出版时间：November 16, 2006
- 年：2006
- 卷：110
- 期：45
- 页码：12355 - 12359
- 全文大小：231K
- 年卷期：v.110,no.45(November 16, 2006)
- ISSN：1520-5215
文摘
We report a new application of fluorescence spectroscopy for the identification and characterization of chemicalspecies in complex environments. Simultaneous collection of a dispersed fluorescence spectrum for everystep of the laser wavelength results in a two-dimensional spectrum of emission versus excitation wavelengths.This two-dimensional fluorescence (2DF) spectrum yields quick and intuitive assignments of a multitude ofpeaks in the separate fluorescence excitation and dispersed fluorescence spectra as belonging to the samespecies. We demonstrate the technique with the measurement of 2DF spectra of a discharge of dilute benzeneinto a supersonic free jet. A multitude of rovibronic bands due to the C2 Swan and C3 comet bands areimmediately apparent and even unreported bands can be assigned intuituvely. Custom software filters areemployed to enhance or reject emission from one or the other carrier to obtain excitation spectra arising frompurely one carrier, or even a specific spectral component of a single carrier. The very characteristic 2DFfingerprints of C2 and C3 permit identification of another unidentified species in the discharge that absorbs at476 nm, coincident with one of the diffuse interstellar bands.