Visualizing vibrational normal modes of a single molecule with atomically confined light

@article{Lee2019VisualizingVN,
  title={Visualizing vibrational normal modes of a single molecule with atomically confined light},
  author={Joonhee Lee and Kevin T. Crampton and Nicholas Ryan Tallarida and Vartkess Ara Apkarian},
  journal={Nature},
  year={2019},
  volume={568},
  pages={78-82}
}
The internal vibrations of molecules drive the structural transformations that underpin chemistry and cellular function. While vibrational frequencies are measured by spectroscopy, the normal modes of motion are inferred through theory because their visualization would require microscopy with ångström-scale spatial resolution—nearly three orders of magnitude smaller than the diffraction limit in optics1. Using a metallic tip to focus light and taking advantage of the surface-enhanced Raman… 
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See how atoms dance
  • J. Aizpurua
  • Physics, Chemistry
    National science review
  • 2020
TLDR
In a new twist in molecular microscopy, the research team in Hefei has managed to combine the information obtained from a set of spectrally filtered ultra-resolved maps of Raman photons emitted from a single Mg-porphine molecule in a plasmonic cavity, and create an image of the molecule where particular vibrational modes of single Figure 1.
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References

SHOWING 1-10 OF 33 REFERENCES
Single-Molecule Imaging Using Atomistic Near-Field Tip-Enhanced Raman Spectroscopy.
TLDR
A systematic theoretical study of TERS imaging of single molecules, using a hybrid atomistic electrodynamics-quantum mechanical method, which provides insights into single-molecule imaging based on TERS and Raman scattering of molecules in nanojunctions with atomic dimensions.
Chemical mapping of a single molecule by plasmon-enhanced Raman scattering
TLDR
Raman spectral imaging with spatial resolution below one nanometre is demonstrated, resolving the inner structure and surface configuration of a single molecule by spectrally matching the resonance of the nanocavity plasmon to the molecular vibronic transitions, particularly the downward transition responsible for the emission of Raman photons.
Ultrahigh-Vacuum Tip-Enhanced Raman Spectroscopy.
TLDR
The advances made in the field thus far demonstrate the utility of TERS as an approach to interrogate single-molecule properties, reactions, and dynamics with spatial resolution below 1 nm.
Molecular-Resolution Interrogation of a Porphyrin Monolayer by Ultrahigh Vacuum Tip-Enhanced Raman and Fluorescence Spectroscopy.
TLDR
The observed TEF spectra suggest a weak coupling of H2TBPP to the substrate due to the bulky t-butyl groups and a possible alternative excited state decay path, thus providing insight into porphyrin-sensitized solar cells and catalysis.
Tip-Enhanced Raman Spectromicroscopy of Co(II)-Tetraphenylporphyrin on Au(111): Toward the Chemists' Microscope.
TLDR
Field-gradient-driven spectra, orientational fingerprinting, and sculpting of local fields by atomic morphology of the junction are elucidated through measurements that range from 2D arrays at room temperature to single molecule manipulations at 5 K.
Theoretical Modeling of Plasmon-Enhanced Raman Images of a Single Molecule with Subnanometer Resolution.
TLDR
A quantum-mechanical description of the interaction between a molecule and a highly confined plasmonic field is reported and the present theory provides the basic framework for describing linear and nonlinear responses of molecules underhighly confined plAsmonic fields.
Tip-Enhanced Raman Spectromicroscopy on the Angstrom Scale: Bare and CO-Terminated Ag Tips.
TLDR
It is shown that nanoscopically smooth silver tips, batch produced through field-directed sputter sharpening, reliably attain TERS with enhancement factors that reach 1013, as measured by the Raman spectra of single CO molecules attached to the tip apex.
Microscopy with a single-molecule scanning electrometer
The single-molecule limit in electromechanical sensing is realized through TERS-relayed molecular force microscopy. The vibrational spectrum of a single carbon monoxide molecule, adsorbed on the tip
Visualization of Vibrational Modes in Real Space by Tip-Enhanced Non-Resonant Raman Spectroscopy.
TLDR
It is predicted that the vibrational motions of different Raman modes can be fully visualized in real space by tip-enhanced non-resonant Raman scattering and this study suggests a feasible approach to spatially visualize vibrational modes.
...
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