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Macroscopic sample shape effect on pulse electron double resonance (PELDOR) signal
Vasyl Denysenkov1, Thomas F Prisner1, Petr Neugebauer2
1Institute of Physical and Theoretical Chemistry and Center of Biomolecular Magnetic Resonance, Goethe University Frankfurt, Max-von-Laue Str. 7, 60437, Frankfurt am Main, Germany.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|October 18, 2023
Summary
Pulse electron double resonance (PELDOR) reveals spin-spin distances. New findings show sample shape and orientation influence PELDOR signals, offering deeper insights into this electron spin resonance technique.
Area of Science:
- Electron Paramagnetic Resonance Spectroscopy
- Solid-State Physics
- Materials Science
Background:
- Pulse electron double resonance (PELDOR), also known as double electron-electron resonance (DEER), measures electron spin dipolar interactions.
- This technique is crucial for determining spin-spin distance distributions in various solid materials.
- Previous studies noted PELDOR signals gain an out-of-phase component under high spin polarization conditions (low temperatures, high fields).
Purpose of the Study:
- To investigate the influence of macroscopic sample shape and orientation on PELDOR signals.
- To understand the underlying physics of the out-of-phase component in PELDOR.
- To provide new insights into the fundamental principles of PELDOR.
Main Methods:
- Theoretical modeling of PELDOR signal behavior.
- Experimental validation of theoretical predictions.
- Analysis of electron spin dipolar interactions.
Main Results:
- The out-of-phase component of PELDOR signals is demonstrably dependent on sample shape and orientation.
- Dipolar interactions between distant spins are identified as the cause of this observed effect.
- The magnitude and sign of the effect are directly linked to sample geometry and magnetic field alignment.
Conclusions:
- Sample shape and orientation are critical factors affecting PELDOR measurements.
- This dependence offers a new avenue for understanding PELDOR signal artifacts and physics.
- The findings enhance the interpretation and application of PELDOR spectroscopy in materials science.
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