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Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo
Published on: September 26, 2016
A multifrequency high-field pulsed electron paramagnetic resonance/electron-nuclear double resonance spectrometer
Gavin W Morley1, Louis-Claude Brunel, Johan van Tol
1Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA. g.morley@ucl.ac.uk
The Review of Scientific Instruments
|July 8, 2008
Summary
We developed a versatile pulsed electron paramagnetic resonance spectrometer for high-frequency studies. This instrument enables detailed investigations of electron spin polarization and electron-nuclear double resonance (ENDOR) experiments.
Area of Science:
- Physics
- Chemistry
- Spectroscopy
Background:
- Electron Paramagnetic Resonance (EPR) spectroscopy is a powerful technique for studying materials with unpaired electrons.
- High-frequency EPR (110-336 GHz) offers enhanced spectral resolution and sensitivity.
- Pulsed EPR techniques provide dynamic information not accessible by continuous-wave methods.
Purpose of the Study:
- To describe the design and capabilities of a novel pulsed EPR spectrometer operating at millimeter-wave frequencies.
- To demonstrate the spectrometer's utility for studying electron spin polarization.
- To showcase its application in pulsed Electron-Nuclear Double Resonance (ENDOR) experiments.
Main Methods:
- A pulsed EPR spectrometer was constructed, utilizing a multiplier chain microwave source (12-15 GHz to 110-336 GHz).
- A fast p-i-n-switch was employed for pulse generation.
- A Fabry-Perot resonator was used, with pi/2 pulse lengths ranging from 100 ns to 600 ns.
- Measurements were performed on Mn(2+) in a single crystal at 12 T and Mims ENDOR on Cr:K(3)NbO(8).
Main Results:
- The spectrometer successfully operated across a wide frequency range (110-336 GHz).
- Measurements on Mn(2+) demonstrated the ability to achieve and study large electron spin polarizations.
- Mims ENDOR experiments on (39)K nuclei in Cr:K(3)NbO(8) were successfully performed, validating the ENDOR capabilities.
Conclusions:
- The developed pulsed EPR spectrometer is a versatile tool for high-frequency electron spin resonance studies.
- The instrument facilitates the investigation of electron spin dynamics and nuclear couplings.
- It opens new avenues for research in materials science and quantum information processing.
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