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Updated: Feb 14, 2026
12:13
Single-Molecule Imaging of Nuclear Transport
Published on: June 9, 2010
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Fingerprints of single nuclear spin energy levels using STM - ENDOR
Yishay Manassen1, Michael Averbukh1, Moamen Jbara1
1Department of Physics and Ilse Katz Center of Science and Technology in the nm scale, Ben-Gurion University of the Negev, Beer-Sheva 85105, Israel.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|February 26, 2018
Summary
Scanning Tunneling Microscopy-Electron Nuclear Double Resonance (STM-ENDOR) precisely measures electron-nucleus couplings. This technique enhances spectral resolution for nanoscale chemical analysis, surpassing traditional Electron Spin Resonance-Scanning Tunneling Microscopy (ESR-STM).
Area of Science:
- Surface Science
- Quantum Chemistry
- Spectroscopy
Background:
- Electron Spin Resonance-Scanning Tunneling Microscopy (ESR-STM) provides insights into electron-nuclear interactions.
- Limitations in spectral resolution of ESR-STM hinder detailed analysis of hyperfine couplings, especially for remote nuclei.
Purpose of the Study:
- To introduce and validate Scanning Tunneling Microscopy-Electron Nuclear Double Resonance (STM-ENDOR) as an advanced spectroscopic technique.
- To demonstrate STM-ENDOR's capability in accurately determining hyperfine coupling constants and nuclear properties at the nanoscale.
Main Methods:
- Performed STM-ENDOR experiments by sweeping radiofrequency power across the tunneling junction while monitoring ESR-STM signal intensity.
- Applied the technique to three distinct systems: SiC vacancies coupled to 29Si, Copper on Si(111)7x7 coupled to Cu nuclei, and Tempo molecules on Au(111) coupled to 14N nuclei.
- Developed and solved Bloch-type equations for the coupled electron-nuclear spin system to interpret experimental data.
Main Results:
- STM-ENDOR accurately determined hyperfine values, including those unresolved by ESR-STM due to linewidth limitations.
- The technique successfully identified couplings to remote nuclei not detectable by ESR-STM.
- STM-ENDOR measured single nuclear Zeeman frequencies, distinguished between isotopes (63Cu, 65Cu), and detected quadrupole spectra.
Conclusions:
- STM-ENDOR offers significantly improved spectral resolution compared to ESR-STM.
- This enhanced resolution enables precise characterization of electron-nuclear interactions at the nanometric scale.
- STM-ENDOR holds great potential for advanced nanoscale chemical analysis and materials characterization.
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