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Title: Resonance Raman Scattering of Rhodamine 6G as Calculated Using Time-Dependent Density Functional Theory

Abstract

The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. In this work, we present the first calculation of the resonance Raman scattering (RRS) spectrum of rhodamine 6G (R6G) which is a prototype molecule in surface-enhanced Raman scattering (SERS). The calculation is done using a recently developed time-dependent density functional theory (TDDFT) method, which uses a short-time approximation to evaluate the Raman scattering cross section. The normal Raman spectrum calculated with this method is in good agreement with experimental results. The calculated RRS spectrum shows qualitative agreement with SERS results at a wavelength that corresponds to excitation of the S1 state, but there are significant differences with the measured RRS spectrum at wavelengths that correspond to excitation of the vibronic sideband of S1. Although the agreement with the experiments is not perfect, the results provide insight into the RRS spectrum of R6G at wavelengths close to the absorption maximum where experiments are hindered due to strong fluorescence. The calculated resonance enhancements are found to be on the order of 105.more » This indicates that a surface enhancement factor of about 1010 would be required in SERS in order to achieve single-molecule detection of R6G.« less

Authors:
;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
921845
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry A, 110:5973-5977; Journal Volume: 110
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; RHODAMINES; RAMAN SPECTRA; SCATTERING; DENSITY FUNCTIONAL METHOD; EXCITED STATES; Environmental Molecular Sciences Laboratory

Citation Formats

Jensen, Lasse, and Schatz, George C. Resonance Raman Scattering of Rhodamine 6G as Calculated Using Time-Dependent Density Functional Theory. United States: N. p., 2006. Web. doi:10.1021/jp0610867.
Jensen, Lasse, & Schatz, George C. Resonance Raman Scattering of Rhodamine 6G as Calculated Using Time-Dependent Density Functional Theory. United States. doi:10.1021/jp0610867.
Jensen, Lasse, and Schatz, George C. Mon . "Resonance Raman Scattering of Rhodamine 6G as Calculated Using Time-Dependent Density Functional Theory". United States. doi:10.1021/jp0610867.
@article{osti_921845,
title = {Resonance Raman Scattering of Rhodamine 6G as Calculated Using Time-Dependent Density Functional Theory},
author = {Jensen, Lasse and Schatz, George C.},
abstractNote = {The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. In this work, we present the first calculation of the resonance Raman scattering (RRS) spectrum of rhodamine 6G (R6G) which is a prototype molecule in surface-enhanced Raman scattering (SERS). The calculation is done using a recently developed time-dependent density functional theory (TDDFT) method, which uses a short-time approximation to evaluate the Raman scattering cross section. The normal Raman spectrum calculated with this method is in good agreement with experimental results. The calculated RRS spectrum shows qualitative agreement with SERS results at a wavelength that corresponds to excitation of the S1 state, but there are significant differences with the measured RRS spectrum at wavelengths that correspond to excitation of the vibronic sideband of S1. Although the agreement with the experiments is not perfect, the results provide insight into the RRS spectrum of R6G at wavelengths close to the absorption maximum where experiments are hindered due to strong fluorescence. The calculated resonance enhancements are found to be on the order of 105. This indicates that a surface enhancement factor of about 1010 would be required in SERS in order to achieve single-molecule detection of R6G.},
doi = {10.1021/jp0610867},
journal = {Journal of Physical Chemistry A, 110:5973-5977},
number = ,
volume = 110,
place = {United States},
year = {Mon Mar 27 00:00:00 EST 2006},
month = {Mon Mar 27 00:00:00 EST 2006}
}
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