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230/115 GHz Electron Paramagnetic Resonance/Double Electron-Electron Resonance Spectroscopy
Franklin H Cho1, Viktor Stepanov2, Chathuranga Abeywardana2
1Department of Physics, University of Southern California, Los Angeles, California, USA.
Methods in Enzymology
|October 20, 2015
Summary
High-frequency Electron Paramagnetic Resonance (EPR) and double electron-electron resonance (DEER) spectrometers were developed. These advanced tools enable complete spin polarization and wide-band DEER for enhanced biological molecule analysis.
Area of Science:
- Biophysics
- Spectroscopy
- Materials Science
Background:
- Electron Paramagnetic Resonance (EPR) and double electron-electron resonance (DEER) are crucial for analyzing biological molecule structure and dynamics.
- Higher frequencies and magnetic fields in EPR/DEER enhance spectral resolution and spin polarization, similar to Nuclear Magnetic Resonance (NMR).
Purpose of the Study:
- To develop a high-frequency (HF) EPR/DEER spectrometer operating at 107-120 GHz and 215-240 GHz with magnetic fields up to 12.1 T.
- To showcase unique experimental capabilities, including complete spin polarization and wide-band DEER spectroscopy.
Main Methods:
- Development and implementation of a novel high-frequency EPR/DEER spectrometer.
- Utilizing frequencies in the 107-120 GHz and 215-240 GHz ranges and magnetic fields from 0-12.1 T.
- Application of HF EPR for spin coherence enhancement in nanodiamonds and HF DEER for spin concentration determination in diamond crystals.
Main Results:
- Successful development of a versatile HF EPR/DEER spectrometer with unique experimental capabilities.
- Demonstrated significant increase in spin coherence in nanodiamonds using HF EPR.
- Accurate extraction of spin concentration in a diamond crystal via HF DEER spectroscopy.
Conclusions:
- The developed HF EPR/DEER spectrometer offers advanced capabilities for studying molecular structures and dynamics.
- HF EPR/DEER techniques provide enhanced resolution and sensitivity for materials and biological samples.
- These advancements open new avenues for high-precision measurements in biophysics and materials science.
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