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Title: Infrared near-field detection of a narrow resonance due to molecular vibrations in a nanoparticle

Abstract

Di-iron nonacarbonyl particles on a gold surface have been imaged using an apertureless near-field scanning infrared microscopy. First and second harmonic detection, with and without an auto-homodyning option, have been used to collect the near-field spectrum of a single vibrational mode of the bridging carbonyls in di-iron nonacarbonyl nanocrystalline flakes on a gold surface. The experimental results have been compared to two theoretical models, a static image-dipole effective medium and an image dipole modified by a Fresnel coefficient for the appropriate observation angle. The calculations have taken into account the roughness of the gold film. The phase dependence of the near-field contrast has been investigated using broadband and tunable CO2 lasers. Particle size effects on contrast and spatial resolution have been studied to determine the limits of applicability of the half-space approximation.

Authors:
;  [1]
  1. (University of Toronto, Toronto, Ontario, Canada)
Publication Date:
Research Org.:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV
Sponsoring Org.:
USDOE - Office of Fossil Energy (FE)
OSTI Identifier:
917419
Report Number(s):
DOE/NETL-IR-2007-245
Journal ID: ISSN 0743-7463; TRN: US200816%%377
DOE Contract Number:
None cited
Resource Type:
Journal Article
Resource Relation:
Journal Name: Langmuir; Journal Volume: 23; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; IRON COMPOUNDS; CARBONYLS; DETECTION; SPATIAL RESOLUTION; NANOSTRUCTURES; INFRARED SPECTRA; MOLECULES; OSCILLATIONS

Citation Formats

Romanov, Vyacheslav, and Walker, G.C. Infrared near-field detection of a narrow resonance due to molecular vibrations in a nanoparticle. United States: N. p., 2007. Web. doi:10.1021/la0625594.
Romanov, Vyacheslav, & Walker, G.C. Infrared near-field detection of a narrow resonance due to molecular vibrations in a nanoparticle. United States. doi:10.1021/la0625594.
Romanov, Vyacheslav, and Walker, G.C. Tue . "Infrared near-field detection of a narrow resonance due to molecular vibrations in a nanoparticle". United States. doi:10.1021/la0625594.
@article{osti_917419,
title = {Infrared near-field detection of a narrow resonance due to molecular vibrations in a nanoparticle},
author = {Romanov, Vyacheslav and Walker, G.C.},
abstractNote = {Di-iron nonacarbonyl particles on a gold surface have been imaged using an apertureless near-field scanning infrared microscopy. First and second harmonic detection, with and without an auto-homodyning option, have been used to collect the near-field spectrum of a single vibrational mode of the bridging carbonyls in di-iron nonacarbonyl nanocrystalline flakes on a gold surface. The experimental results have been compared to two theoretical models, a static image-dipole effective medium and an image dipole modified by a Fresnel coefficient for the appropriate observation angle. The calculations have taken into account the roughness of the gold film. The phase dependence of the near-field contrast has been investigated using broadband and tunable CO2 lasers. Particle size effects on contrast and spatial resolution have been studied to determine the limits of applicability of the half-space approximation.},
doi = {10.1021/la0625594},
journal = {Langmuir},
number = 5,
volume = 23,
place = {United States},
year = {Tue Feb 27 00:00:00 EST 2007},
month = {Tue Feb 27 00:00:00 EST 2007}
}
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