Related Experiment Video
Updated: Aug 11, 2026

Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels
Published on: July 4, 2016
Angular variation of linewidths in single-crystal EPR spectra
Søren K Klitgaard1, Frode Galsbøl, Høgni Weihe
1Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark.
Electron paramagnetic resonance (EPR) studies reveal the magnetic field and linewidth variations in chromium-doped rhodium complexes. While the cation exhibits axial symmetry, some paramagnetic sites deviate from this ideal symmetry.
Area of Science:
- Coordination Chemistry
- Solid-State Physics
- Spectroscopy
Background:
- Electron paramagnetic resonance (EPR) is a powerful technique for studying paramagnetic species in various environments.
- Chromium(III) and Rhodium(III) complexes with chiral ligands are of interest due to their unique electronic and structural properties.
- Single-crystal EPR spectroscopy provides detailed information about the local symmetry and electronic environment of paramagnetic ions.
Purpose of the Study:
- To investigate the magnetic properties and local symmetry of Delta+ [Cr((-)chxn)3]3+ ions doped into a Delta+ [Rh((-)chxn)3]3+ host lattice.
- To analyze the angular dependence of resonance magnetic fields and linewidths in single-crystal EPR spectra.
- To determine the degree of axial symmetry in the paramagnetic sites.
Main Methods:
- Single-crystal electron paramagnetic resonance (EPR) spectroscopy was employed.
- The angular variation of resonance magnetic fields was measured.
- The angular variation of spectral linewidths was analyzed.
Main Results:
- The angular variation of resonance magnetic fields confirms the presence of axial symmetry for the cation.
- Analysis of the angular variation of linewidths indicates that not all paramagnetic sites possess perfect axial symmetry.
- Deviations from perfect axial symmetry were observed in the linewidth data.
Conclusions:
- The study successfully characterized the magnetic properties and symmetry of the doped chromium complex.
- The findings highlight the sensitivity of EPR linewidth analysis to subtle distortions in paramagnetic sites.
- This research contributes to understanding the structural and electronic nuances of coordination complexes.
More Related Videos
08:01Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo
Published on: September 26, 2016
10:32Sample Preparation and Transfer Protocol for In-Vacuum Long-Wavelength Crystallography on Beamline I23 at Diamond Light Source
Published on: April 23, 2021
Related Concept Videos
NMR Spectrometers: Resolution and Error Correction
Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals
¹H NMR: Interpreting Distorted and Overlapping Signals
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
X-ray Crystallography
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
According to Hooke's law, the vibrational frequency is directly proportional to the...
IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations